When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
very nice write up, i have only one small question. whats up with the copper pipe wedged between the exhaust and the rear diff???? why not just hang the pipes so they dont hit? what am i missing?
very nice write up, i have only one small question. whats up with the copper pipe wedged between the exhaust and the rear diff???? why not just hang the pipes so they dont hit? what am i missing?
It is very difficult to hang the exhaust pipes using stock spring loaded hangers without the exhaust being tight against the differential. I did not want that heat directly on the differential and did not want the pipes moving up and down on the spring loaded hangers banging against differential. This was a way of FIXING the gap between the exhaust pipes (each exhaust pipe) and differential to 1/4 inch.
The copper pipe is placed across the tops of the exhaust pipes allowing the spring loaded hangers to pull and hold the exhaust pipes against the copper pipe while creating a 1/4 inch gap between the exhaust pipes and the differential. Copper does not corrode and transmits heat very well. The copper pipe is captured by the four bolts of the rear Leaf Spring bracket.
SW Headers ZR1CORVOR and SW Exhaust ZR1CHAMSW were installed in both the 90' and 91' with this copper pipe setup.
The Copper pipe spacer was added (two each 1 x 6 inch copper pipe with coupler and end caps) to keep SW exhaust 1/4 inch
away from riding against Differential Housing. The end caps and coupler actually keep the spacer in place without any ties.
I set the two rear stock spring hangers so they pull the exaust up tight against the copper spacer. Also set the rear "L" hanger so there is freedom of the exhaust system to move to the rear at least 1/2 inch when hot.
It is just a bit easier with TB coolant path in place as that makes it easier to vent air in the coolant system to the Surge Tank on initial start up (before the thermostat opens). There are two engine outlet tubes (injector Housing coolant manifolds (Left and Right). Before the Thermostat opens they allow hot coolant (with some entrapped air) to go back into the engine directly. It is during this period before the thermostat opens that the TB coolant path allows some of this entrapped air get back directly to the surge tank.
After the Thermostat opens the Injector Housing Coolant Manifolds vent Hot coolant (with any entrapped air) to the top of the radiator. After the water pump is fully engaged with no air lock and at the higher flow rates (higher rpms) it makes no difference if the TB coolant is blocked. Any air found in the high spots of the injector housing coolant manifolds is flushed out to the top of the radiator and then to the surge tank by the shear volume of coolant flow in the injector housings. There is a tube on the passenger top side of the radiator that allows air to be forced back to the coolant surge tank during coolant expansion as the coolant heats up.
Originally Posted by PhilipJFry
Would the procedure be any different if the TB wasn't blocked. Also is the Driver side "L" the Engine Coolant Outlet tube?
Originally Posted by Dynomite
Disconnect that drivers side Injector Housing "L" before you close the radiator drain as more coolant will drain with that hose disconnected...then close the radiator drain before you start adding coolant......
Originally Posted by Dynomite
Originally Posted by PhilipJFry
Do you have a step by step directions on flushing the coolant on the Z? I can't seem to find anything on it.
Well....simply open the drain bottom passenger side of radiator with cap OFF surge tank in front of passenger side. Let it drain. You will not get ALL the coolant removed which is normal. I would then disconnect the Drivers side "L" from Drivers Side Injector Housing Coolant Manifold. Rotate that hose upward and slowly fill with GREEN (I use NAPA GM1825) Antifreeze. When it will not take anymore coolant, blow into that hose forcing coolant into the water pump chambers until coolant seeps out of the Drivers side OPEN Injector Housing Coolant Manifold.
Reconnect that hose to the Drivers Side Injector Housing Coolant Manifold.
Then Slowly fill the passenger side surge tank just in front of the passenger side firewall. Also fill at least 3/4 full the passenger side Coolant Overflow tank under passenger side headlight. Replace the pressure cap on the surge tank.
Start and run the engine for a minute or so with your hand on both Right and Left Injector Housing Coolant Manifolds. The should start getting warm within 30 seconds of start up. If they are not getting warm after a minute, shut it down as you prolly have an air locked water pump.
That would be extremely rare if you do as above.
If the injector housing coolant manifolds are getting warm, shut it down and fire it up again in a couple minutes and let it run longer as the Injector Housing Coolant manifolds will gradually get HOT......followed by the top radiator hose getting warm indicating the thermostat is opening up allowing coolant to flow through the radiator. Once the radiator hose gets hot you are in business ....just take it for a spin and then shut it down letting the radiator suck coolant back out of the overflow tank under passenger side headlight. Keep that 3/4 full for the first few trips as the engine will gradually push the last bit of air out of all the voids exchanging with coolant from the overflow tank.
This is the process I use with TB coolant blocked which is the most complicated case of LT5 engine coolant flushing.
Engine Oil
I use a Mobile M1-207 Oil Filter.
Change Engine Oil normally every:
Annually if I do not get the 2,000 miles. 2,000 miles (City Driving).
4,000 miles (Cross Country).
Transmission Oil will be changed every 10,000 miles as Bill Boudreau suggests.
Differential Fluid
I install Differential drain plug to get ALL the fluid removed and add New Differential Fluid on all ZR-1s when I take possession of ZR-1s.
Brake and Clutch Fluids
Clean out reservoirs and add New DOT 4when I take possession of ZR-1s.
Drain Coolant and add NAPA coolant (GM 1825M)when I take ppossession of ZR-1s. See LT5/ZR-1 Fluids
Tech Info - LT5 Eliminated Systems The LT5 runs perfectly with all that is eliminated described here. Marc Haibeck has addressed all items in a modified Low 87 Octane and a High 91 Octane Chip.
1. Eliminating Secondary Throttles/shafts.
Install Dorman freeze plugs 555-108 with Loctite 262 to plug the secondary shaft ports for a complete elimination of Secondary throttle shafts and associated vacuum canisters (90 Heads on Left and 91 Heads on right). Summit Racing Freeze Plugs 555-108
Marc Haibeck mentioned to me some time ago....Haibeck Automotive Technology
Removing the secondaries is not a bad idea. Marc dyno tested removing the secondary throttles and found no significant changes.
Marc suggested there are three situations where removing the secondaries are useful.
1. If you are having a problem with them that you can't fix, they can be eliminated.
2. If you can't find a repair part.
3. If you have removed them to port the heads, you can save time and not reinstall them.
Marc also mentioned that removing the secondaries does not effect the idle, fuel economy or torque over 1500 rpm. Having the secondaries in place might be an advantage for an emission test.
Further, with the elimination of the secondary port throttle control the engine idles on the primary injector only. When the main throttle is opened to about 1/2% or more the secondary fuel injector activates. This usually happens while the clutch is being slipped to drive away, typically the engine is running on both fuel injectors before the clutch fully engages. Once the throttle is more than 1/2% open the flow split between the primary and secondary injectors is the same as the OE value of 50%-50% and in sync with each other.
I might also mention eliminating the associated vacuum system and secondary cannisters gets rid of a lot of potential failures later on and makes for a clean looking LT5 installation.
Also keep in mind eliminating the air injection system may have ramifications in regard to a SMOG check depending which State you reside. I have also eliminated the original Exhaust Manifolds and CATS which would be required in some States for SMOG check success.
2. Eliminating Secondary Throttle Vacuum system.
There are two vacuum sources (Electric Vacuum pump and Plenum).
Remove everything except the diagnostic vacuum sensor that is located under the ECM. The sensor is connected electrically and the hose nipple open to the atmosphere. Remove all of the vacuum lines, the Secondary Vacuum Reservoir, the solenoid valve and the electric vacuum pump. Use Marc Haibeck CHIP's Marc Haibeck
Secondary Vacuum System
Diagnostic Vacuum Sensor
There are two vacuum check valves under the plenum (one connected to HVAC tank and one connected to Secondary vacuum reservoir). The check valve connected to HVAC tank (via the "Y" cited below for Eliminating Air Induction System) remains in position connected to passenger side source of plenum vacuum and connected to the HVAC vacuum line in the harness to rear of plenum.
The check valve connected to the Secondary Vacuum Reservoir and drivers side source of plenum vacuum can be capped off since the Secondary Vacuum Reservoir is eliminated. This is shown in the Eliminating TB coolant system picture below.
3.Cruise Control/HVAC and EVAP Purge System.
The Cruize Control/HVAC Vacuum is taken from the passenger side of plenum. From there one vacuum line goes to the Cruize Control under ECM/Brake Cruize Vacuum Release (one line) and the second line goes to the HVAC System through the passenger side Fuel Injector Wire Harness (second line). The Vacuum line to the Cruize Control includes the Cruize Control Vacuum Reservoir under Drivers side Headlight which is left in place. The other vacuum hose connected to the Cruize Control is for the brake pedal cruise cancel function.
The EVAP Purge system (1991 ZR1) draws vacuum from under front of Plenum and through the Solenoid valve. When the Solenoid valve is activated, vacuum is directed out the right side under Plenum back along the passenger side frame rail to the Charcoal Canister directly behind the Passenger Side rear wheel. The 1990 ZR1 Charcoal Canister is located under the Drivers Side Headlight. (Vacuum for the 1990 Charcoal Canister is taken from the drivers side front of Plenum as well as a vacuum line from beneath the front of the Plenum. SeeVacuum Systems 90' and 91' (Secondary and Cruize/HVAC)
Cruize Control and HVAC Vacuum System .....................EVAP Purge Vacuum System (1991) with Solenoid
Marc and Pete suggested to eliminate the EVAP Purge circuit completely and capping off that vacuum source under front of plenum. I just replaced my charcoal canister and Marc says he does not address that removal in the chip as it has no effect. I left that associated vacuum and electrical connection including the Evap Purge solenoid in place under the plenum.
This discussion and photo is for a 1991 which has the Charcoal Canister just to the rear of the passenger side rear wheel. The 1990 has the charcoal canister under the drivers side head light so the Vacuum Connections for Charcoal Canister are different as well as the vacuum lines which for the 1990 you will not find the large loop for charcoal canister under the Plenum.
4. Eliminating Throttle Body (TB) Coolant system.
Install 1/8 inch NPT allen head pipe plugs (21/64 or 11/32 drill) two each side of Plenum (Two each TB Coolant and Injector Housing (IH) Coolant) as shown (The associated two IH coolant ports in the IH should also be plugged on each side). Total six coolant ports plugged One each side TB, One each side Plenum, One each side Injector Housing.
See Summit Racing for Aluminum Pipe Plugs.When you install the plugs.....keep trying the plugs as you tap to make sure the final installation is about flush or out 1/16 inch and use Permatex on the plugs.. The Injector Housing Plug must be FLUSH however.
Remove TB Coolant hose and tubing left and right side of plenum and plug hose return to coolant tank passenger side See Brass Cap just above the "T" on Passenger Side. Initial Coolant Fill may be somewhat affected by the TB Coolant Elimination (see item #4 Initial Coolant Fill). The "T" connects the top of the radiator Air Vent, TB Coolant Return, and Coolant Reservoir in front of Passenger side. With the TB Coolant Return Blocked, what is left is a coolant line from the Radiator Air Vent to the Passenger Side Coolant Reservoir.See (Filling With Coolant and the Air Locked Water Pump) for Detailed New Coolant Filling Trick.
A brass nipple that fits tight inside the rubber hose with a male 1/4 inch pipe thread and a 1/4 inch Brass pipe thread cap (female thread)
I left about 2 or 3 inches of rubber hose above the "T" that connects (did connect) the TB vent, Radiator top vent, and Coolant surge container in front of passenger side (the highest point in the LT5 Coolant System).
Note 1: The TB coolant path back to the passenger side overflow tank does provide a path for air and potential air lock to return to that passenger side tank during initial coolant fill. However, the Plenum to TB coolant hose sits only an inch or so above the IH coolant manifolds on the passenger side so the benefit of using that path to bleed air vice the top of the coolant manifolds to the radiator is very small. Marc has decided to bypass the TB coolant (vice eliminate all TB coolant hoses) leaving that coolant path back to the passenger side overflow tank in place to assure issues would not arrise on rebuilds for those unaware of coolant initial filling and water pump potential air locks.
The 5th plug (Plenum Vacuum) is for Plenum Vacuum drivers side only which was connected to the vacuum reservoir. The tubing can be removed and a 1/8 inch NPT allen head pipe plug inserted exactly like the plenum coolant plugs.
a.When you run the tap....keep checking the pipe plug for depth so you end up tight and flush. b.When you run the Drill.......remember you are in ALUMINUM so go very easy and slow!!! (you can do it without a drill press). c. Use a bit of Permatex gasket sealer or Teflon tape on the pipe plugs.
5. Eliminating Air Injection system.
The Air Injection System including the Air Pump has been eliminated (especially for those who are installing Headers). Associated with the Air Injection system is one vacuum line on the drivers side fender skirt above the shock tower. I eliminated the "T" and just moved the "Y" in front of "T" about 3 inches and plugged the "Y" back in where the "T" was. This modification maintains the Cruise Control Vacuum and the associated Vacuum to the Cruise Control Vacuum Reservoir under the Drivers Side Headlight.
The PCV pipe along the plenum drivers side from PCV valve at rear of Plenum to Plenum Vacuum at front of Plenum eliminated. Stainless steel braided hose is used from the PCV valve at rear of plenum to Oil Catch Can (LT5 Added Systems) and then on to the Plenum Vacuum.
The PCV hose connected under front of plenum (Vacuum source) is connected using SS braided hose to an Oil Catch Can external to the engine which Oil Catch Can is connected to the dual PVC valves hard line located at the rear of the plenum. The MAP sensor (located at rear of plenum) is connected to the rear of plenum (Vacuum source).
SW Offroad Headers. As you know it is difficult to install headers with LT5 in the ZR1. With engine out I was able to install 14 of the 16 header bolts with locks (on each Header) in just a few minutes.
Installing the the LT5 with Headers Installed is easy if the LT5 is tilted to the rear considerably. The LT5 has to be prevented from rolling from side to side. Leave the Fuel Rails, Plenum, and Bell Housing OFF untill after the LT5 is installed in the ZR1.
1. You definitely need a load leveler (to UNLEVEL or tilt the LT5 to the rear).
2. You CANNOT use the standard lift eyes for the LT5 because as you load UNLEVEL (Tilt engine to the rear) the engine rotates if you lift LT5 on diagonals.
3. You have to lift with nylon straps around Flywheel (rear) and around Harmonic Balancer (front). Actually around more stuff on front.
4. You have to remove the A/C Temperature sensor cover (passenger side firewall) and Wiper Motor (Drivers side firewall). SeeHow to Replace the Wiper Motor.
5. You DO NOT have to remove the hood and the ZR1 can sit on the level.
A/C Temp Sensor........................Wiper Motor.............Do NOT use standard Lift Eyes installing LT5 with Headers
1. Reground Camshafts and ....................2. Oil Pressure Sensor Modification. Billet Aluminum Camshaft Retainers............The oil pressure sensor has been modified LT5 Camshaft Specifications........................by adding a brass T fitting which can also ........................................ ........................be used to attach a mechanical oil pressure gauge.
3. 91' ZR1 (LT5) Debree Screen.
Use 1/8 inch steel pop rivets with washers backside of air deflector and on front of screen
(approximately 5/16 inch mesh). Drill 1/8 inch holes in the rubberized air deflector.
Use cable ties on top side of screen.
4. Differential case drain installation
Installed an aftermarket Differential Case Drain Plug for easy fluid change.
The kit is available from Corvette Central Differential Drain Plug Kit
I placed the Differential Drain Plug just on the Drivers Side of what I call the Molding Seam in the Center of the Flange Thickness.
The kit provides a template that puts the hole just left of the center bolt in the valley of the differential.
Original Photos provided by Scrrem with Red notes added.
The tap size is 1/8-27 pipe and it installs easily with drill (11/32) and tap supplied in the kit.
I drilled the bottom flange just under the ring gear and let the old fluid drain (which drained in about 10 minutes). I then tapped the drilled hole for the 1/8 inch allen pipe plug. When you tap the hole, try the pipe plug several times as you tap so you end up with the pipe plug out maybe 1/16 inch when tight . Use Permatex on the Aluminum or Brass 1/8 inch Allen Pipe Drain Plug.
I inserted the 1/8 inch allen pipe plug and pumped in a bit over 3 pints of Mobile 1 75W-90 into the fill port on the North side of the differential (Z facing West)
The Differential case can be COMPLETELY drained and flushed with new oil using this method as compared to trying to suck out the old oil.
The PCV hose connected under front of plenum (Vacuum source) is connected using SS braided hose to an Oil Catch Can external to the engine which Oil Catch Can is connected using SS braided hose to the dual PVC valves hard line located at the rear of the plenum. The Oil Catch Can is located on the drivers side inside wheel well (using a small channel ground and drilled to conform to the inside fender well as a spacer).
In addition to the Oil Catch Can, a new PCV dual top connector has been added replacing the old connector.
You can see the size of the PCV Connector openings (Jerry's new on left and old on right in each photo). Replacing these with Jerry's NEW PCV top connector (on left in each photo) is a must
60 / 80 AMP RELAY SPDT SINGLE POLE DOUBLE THROW NEW 654
Installed under ECM and in slot between brake booster and fire wall (perfect place for location of Relay).
Wiring modified a bit to assure Pin #87a is not hot at any time.
Pin #30: Purple wire to starter (use 3/8 inch connector on relay).
Pin #87: Red wire battery positive 12v use 3/8 inch connector on relay (connected to battery positive multiple connection post).
Pin #86: Battery ground (1/4 inch connector on relay connected to ground where battery 12 gauge wire grounded).
Pin #85: Purple wire from ECM use 1/4 inch connector on relay (Red wire on early 1990 ZR-1).
Pin #87a: Not hot at any time and not used.
Insert a short 1/2 inch long section of plastic hose
over the center connector on the Relay which is NOT
used in this application.
8. Billet Aluminum Alternator Pulley (MCH-208)
The MCH-208 is the same Diameter as the Stock Pulley.Actually the MCH-208 is just a tad larger diameter.
The Offset of the MCH-208 is identical to the Stock Pulley.
The Stock Pulley has a removable Offset Collar which is NOT used in the installation of the Aluminum Pulley.
This Pulley can be installed without removing anything including the Serpentine Belt (except the Original Alternator Pulley).
Look for MCH 208 on Summit Racing MCH-208or Ebay MCH-208
Oh.....by the way.....I just invented a New Way to install the Serpentine Belt......Remove the Alternator Pulley (takes 1 minute) and position NEW Alternator Pulley inside Serpentine Belt and lift up the Alternator Pulley and Serpentine Belt with Belt Tensioner compressed (Keep Serpentine Belt aligned with Belt Tensioner Pulley). Now just slip the Alternator Pulley onto the shaft (very easy to do and plenty of play) and tighten up the 15/16 inch Alternator Pulley Nut.
Lastly......install the Aluminum Alternator Pulley Cap with the three Allen Head Bolts provided with just a little torque as they are threaded into Aluminum.
The PCV hose connected under front of plenum (Vacuum source) is connected using SS braided hose to an Oil Catch Can external to the engine which Oil Catch Can is connected using SS braided hose to the dual PVC valves hard line located at the rear of the plenum. The Oil Catch Can is located on the drivers side inside wheel well (using a small channel ground and drilled to conform to the inside fender well as a spacer).
The Oil Catch Can is attached to the Plenum PCV Vacuum port connector shown (the 12 inch SS Braided hose with hose clamp).
The fuel tank EVAP purge system goes through the electrical switch control under the plenum (shown) and out the passenger side back under the passenger side frame rail on a 91' having the Charcoal Canister on the passenger side behind the rear tire. The 90' Purge
Connection comes straight out and is connected to the Charcoal Canister located under the drivers side Headlight.
3. Oil Catch Can Parts.
The two hose fittings are (Hose End, Swivel, 90 Degree, 6 AN Hose to Male 1/4 in. NPT, Aluminum, Nickel) and the 1/4 NPT is screwed into the Oil Catch Can 1/4 inch NPT threaded holes Swivel, 90 Degree, 6 AN Hose to Male 1/4 in. NPT
On the other end of the SS Braided hose install 6 AN Straight Hose End which fits into a 5/16 short rubber hose connected to the Plenum PCV fitting.
The hose is 6-AN Summit Racing SS Braided hose 6 AN SS Braided Hose. The Elite Engineering Oil Catch Can does not come with the fittings cited herein. Replace the fittings of the Elite Engineering Oil Catch Can with the two SS 90 deg 6 AN to Male 1/4 NPT pipe fittings cited herein.
The short SS Braided Hose section connected to the Plenum PCV vacuum is 12 inches long. The longer SS Braided Hose section connected to the PCV connector is 24 inches long. A brass 5/16 inch diameter nipple is plugged into the black PCV stock connector shown. The other end of the 5/16 inch diameter nipple is plugged into the SS 6-AN hose with hose clamp (as shown).
4. Mounting of Oil Catch Can to Fender.
The Oil Catch Can is mounted on the Drivers side Fender using two Allen Head 8mm x 1.25 bolts (1-1/4 inch long) with Wing Nuts and washers on the outside of the fender well.
The bracket adapter (to which the Oil Catch Can Hanger is mounted) is made from a 1-1/2 x 1/2 inch channel 5-1/2 inches long with the flanges ground to fit contour of inside of fender well.
5.Cruise Control and EVAP Purge System.
The Cruize Control Vacuum is taken from the passenger side of plenum. From there one vacuum line goes to the cruize control under ECM (one line) and the second line goes to the cruize control switch on steeringwheel column (second line).
The EVAP Purge system draws vacuum from under front of Plenum and through the Solenoid valve. When the Solenoid valve is activated, vacuum is directed out the right side under Plenum back along the passenger side frame rail to the fuel tank.
Cruize Control Vacuum System ...................................EVAP Purge Vacuum System with Solenoid
How to Remove Injector Housing Coolant Manifold Torx-30 Bolts
How to Remove Injector Housing Coolant Manifold Torx-30 Bolts
This Procedure can be used with Injector Housings removed or NOT removed from the Engine.
Apply Heat to each area of the Injector Housing/Coolant Manifold for each bolt separately. I use Acetylene Torch. Just a bit of heat around the area and try the bolt....then a bit more heat and try bolt again.
Apply HEAT to the Coolant Manifold area for each bolt in addition to the Injector Housing bolt threaded area because many times the resistance to torque is the fact the length of bolt through the Coolant Manifold is frozen with corrosion within the Coolant Manifold bolt hole.After each bolt is removed, you may use a paper towel dipped in cool water to get the area just heated cooled down quickly before heating up the area for the next bolt.
Then on to next bolt. The secret to removing the Torx-30 x 50mm bolts is to apply torque WITHOUT STRIPPING the Torx. Never Strip the Torx.
Just apply torque on the Torx-30 and keep upping the heat and do it quickly so you do not Heat up the Whole Injector Housing Gasket to Head too much.
Then......follow up with a 6mm x 1.00 tap into the Injector Housing for each of the Torx-30 bolts. I always replace he original (often corroded bolts) with Jerry's Allen Head Coolant Outlet Pipe BoltsJerry also has these bolts in Stainless Steel Allen Head.
I had a NO START condition on a 90' and after I towed it for a start....got home and it fired right up. I would have liked to hot wire the starter (purple wire) when that happens to see if it is the starter or starter ground circuit. Or check that purple wire for 12 volts when I turn the switch to start. I lean toward ground circuit or sticky starter solenoid. Another indication would be if when you turn the ignition key to start do the lights dim for example indicating a current draw to the starter solenoid/starter.
If the solenoid does not move (no clicking indicating the Starter Solenoid moved) as in my case then a sticky Solenoid or Solenoid Ground Connection. If the Solenoid clicked/moved...then bad Solenoid contacts or bad connection Battery cable (Positive) to starter/battery or bad ground (Negative) engine to battery.The moving Solenoid contacts can be easily wire brushed and the fixed contacts can be easily shined up with emery cloth. Also use a bit of WD-40 on the plunger when re-installing.
Installed a relay in the start circuit of the 90' identical to what I have on the 91'. This is one of those intermittent issues and does sound like poor electrical connections in either the Starter Negative Connections or Starter Positive Connections. A poor condition electrical circuit to and through the Solenoid causing a weak magnetic field which moves the plunger will result in poor contact of the main contacts which will result in lower voltage to the main starter circuit.
Check the two bearings on each end of the Armature for roughness by spinning with your fingers. If any roughness, replace with new bearings (pulling the bearings with a small bearing puller).
1. Removing Clutch Slave Cylinder.
I was under my 90' most of the day fooling around with the Slave and Master Clutch Cylinder....I had an extra Slave and Master Cylinder but bleeding that ^&^*^&*%^$&#((*&(....well you get the picture. I just ordered a NEW Master Cylinder and Slave Cylinder from Jerry.
It turns out I could remove the two nuts on the Slave Cylinder and slip it out from the studs and down (the hard line will slip between the bell housing and drivers tunnel). The hard line has a rubber hose section about 12-18 inches from the hard line (a 12 inch more or less section of rubber hose between two hard lines). This rubber hose section allows the Slave Cylinder movement flexibility which allowed me to move the Slave Cylinder down below the exhaust pipe. I used a 13mm open end on the tube connection on the Slave Cylinder. Loosen that connection and remove the tubing from the Slave Cylinder.
Now it you are saying the New Slave Cylinder is a bit different and cannot be installed as easy as the old Slave Cylinder was removed.....let me know as I will run into this issue myself next Tue when I receive the New Master Cylinder and New Slave Cylinder from Jerry :handshak:
2. Bleeding Clutch Master/Slave.
First tighten the fitting on top of Clutch Slave Cylinder so steel line us parallel with Slave Cylinder. Loosen bleeder. Depress Slave Cylinder shaft and insert into bell housing such that shaft us centered in bell housing port then depress Slave cylinder shaft further to install nuts on Slave Cylinder studs.
Now.......fill (2/3 full) Master Cylinder reservoir with DOT 3 or DOT 4. As someone pumps clutch, open bleeder on Slave Cylinder each pump untill you get fluid. Close Bleeder. Continue to pump clutch holding 5 sec each time and release for 5 seconds. You will see some bubbles each release in Master Cylinder Reservoir. Continue untill you have Clutch release (keep Clutch Master Cylinder Reservoir 2/3 full at all times). Fill Master Cylinder Reservoir 3/4 full as Clutch Slave will continue to self bleed as you drive.
Billet Aluminum Wire Separators with ALL Stainless steel Attachments.
A. Complete Sets of Spark Plug Wire Separators.
1. 1/2 x 1/4 8-18 SS washer (washer shown before and after modifications) from Ebay.
2. I think m3 x 1-1/4 2.5mm allen head SS machine screw (MACS in South Dakota).
3. Black Plastic (4 wire) Wire Separators from Summit Racing
Ignition Wire Looms and Separators
4. Wire Separators (Billet Aluminum) from Ebay.
5. I show a SS Allenhead Plenum Bolt I got from Jerry.
B. Fabrication of the Wire Separator Attachments.
I drilled the 1/4 inch hole in the washer out to 5/16 inch.
I used a cut off grinder and bench grinder to form the SS Tab from the larger SS Washer.
I drilled the smaller hole (5/32 inch) in the SS Tab made from the washer to take the m3 SS Allen Head Machine Screw. In the final design a bit more distance between the m3 SS Allen Head Machine Screw and the
Plenum Bolt (Torx or SS Allen Head).
I then inserted the m3 SS Allen Head Machine Screw into the SS Tab made from the SS Washer.
I then pushed the SS Allen Head Machine Screw into the Black Plastic 4 wire Separator so the Black Plastic Wire
Separator was tight up against the SS Tab.
It turns out that the m3 SS Allen Head Machine Screw takes a 2.5 mm Allen Head Key which is the same size key
required by the Billet Aluminum Wire Separators.
Oh.....we are talking nickel and dime for the parts shown.
The Battery Disconnect Switch and Having an Operational Secondary Full Power Switch
1. Battery Disconnect Switch.
The Battery Disconnect Switch comes as close as one can get to "Maintaining The Battery at its Optimum Charge". I do loose Radio Presets but only use the CD anyway. SEE Discussion Use of Battery Disconnect Switch
There is an additional ADVANTAGE not mentioned (I think)......Disconnecting the Battery Erases Codes that do not seem to reappear nearly as often if at all.
When Battery Reconnected and the Engine Started, the Idle functioned exactly as before Settling into the 850 range within about 5 seconds of starting after an initial Higher Idle Speed. So the ECM definitely remembered that. The CHIP Information is NEVER Erased.
Try the Battery Disconnect....you might like it I have tried Battery Tenders and do not like them as I do NOT like having to plug them into an outlet or having to park the ZR1 near an outlet. Or worse having to route an extension cord around other equipment and having to keep Main Power on in the Shed/Garage just to support a Battery Tender. I also do not like Unattended Electrical Power plugged into the ZR1 just in case of a Short in any particular Component or electrical corrosion of that component because it is in a LONG TERM HOT Unattended condition.
ALSO....what better Anti Theft than to have your hood locked and Battery Disconnected.
With the Battery Disconnect you can Disconnect your Battery as often as you like without wearing out the Original Battery Negative Terminal on either the Battery or on the Negative Cable Connector.
2. An Operational Full Power Swtich.
I have one ZR-1 with secondaries removed and three ZR-1s with secondaries functioning perfectly.
Having the ZR-1 Full Power Switch is an additional unique capability of the LT5 System. See Item #2CMHSL LED, Full Power Key and Alternator Pulley See Power Key Rebuild TIPS
The TRICK to a fun to have secondary system is a vacuum system with no leaks.
Check the two bearings on each end of the Armature for roughness by spinning with your fingers. If any roughness, replace with new bearings (pulling the bearings with a small bearing puller).
5. Install Jerry's New PCV Hoses, Connectors and Grommets. I installed Jerry's New Dual PCV Connectors on ALL engines getting rid of all the Clap Trap Nylon Ties and Hose Clamps to keep the Old (hardened Rubber) Dual PCV connectors from slipping off the connectors or leakingHighly Recommended Right up near Top Of List with Blocking TB Coolant at each Injector Housing.
6. Change Plug Wire Bracket Location from IH to Plenum.
Along with the PCV Upgrades is the raised Plug Wires from Injector Housing Bolt to Plenum Bolt on ALL engines. This keeps the plug wires from riding on the cam covers. This also allows the Dual PCV Connector to be attached in front of and at the same location as the Plug Wires and above the Cam Covers.
Just have to say this one more time.
These ZR-1s are over 20 years old and many have not had the Injectors replaced, Starter Reconditioned, or even the Plenum removed.
Time for some Maintenance. And it only takes three days......one day to remove Plenum and clean up area under Plenum, One day to relax and think when engine is drying out from HOT Pressure Wash, One day to put it all back together with new Plenum Gasket (and some other stuff) from Jerry .
You may have to wedge the handle with wood at the air horn and you may have to reach down and rotate the belt tensioner just a tad to get the 1/2 inch socket inserted.
Slip the new belt on edge between Harmonic Balancer and frame rail first using a wooden or similar yard stick to poke the belt between the tight space on edge.
Then guide belt up around Power steering pulley, over AC with a tight fit under Air Horn (Rubber Air Intake bellows removed), then down under Water Pump Pulley, then loop up and held near Alternator. The other end pulled up from Harmonic Balancer after it is matched rib for rib on the Harmonic Balancer.
Pass the back side of belt over Belt Tensioner Pulley. Now.......with 1/2 inch socket inserted, open Belt Tensioner and hold tight the belt loop to keep belt in place groove for groove on the Power Steering, AC, and Harmonic Balancer Pulleys.
With pulleys matched grove for grove (Power Steering, AC, Harmonic Balancer), Slip Belt loop over Alternator Pulley and match groove for groove.
Release Belt Tensioner and assure there is approximately 1/2 inch between the inside of the belts at the Belt Tensioner.
If you cannot slip the belt over the Alternator Pulley with all grooves on the pulleys mentioned matched groove for groove and if there is not the approximately 1/2 inch gap between inside of belt and inside of belt at the belt tensioner, maybe check belt length.
You can check belt length by running a tape measure on the outside of the belt (with the belt) as you run the belt and tape measure through your fingers.
I like my LT5 running around 190 deg F to 200 deg F (maybe 215 deg F on HOT 100+ deg F days) for condensation and best performance. I use the Haibeck LT5 Performance Chips in ALL ZR-1s which turn Fans ON at 205 deg F and OFF at 200 deg F.
Now also keep in mind you are pulling air through a three stack set up including the AC condenser, Oil Cooler, and Radiator.That is where the pusher fan concept will help in stop and go traffic or at stop lights if you want to go that route. I think Daryll (AKA Goldcylon) experimented with higher flow rate dual fans which would also help keep LT5 Coolant temperatures down on HOT days.
A. Now where I think concepts are over blown............. The steady state of the coolant flow is identical at HOT ambient temperatures (100+ deg F) no matter when the fans first came on and no matter when the thermostat first opened. (kind of like using lighter weight front of engine pulleys or lighter weight flywheels where the hp gain is only on rotational acceleration and not on the steady state of engine RPM).
Using 165 deg F or anything less than 180 deg F thermostats is a bit of a waste and a negative on colder days. A 180 deg F and a 165 deg F thermostat are both fully open at the LT5 operational temperatures I am seeking of 190 deg F - 200 deg F (maybe 215 deg F on HOT 100+ deg F days). Yes you may if other modifications allow it on 100 deg F days drive around at 175 deg F and approach a stop and go situation with a cooler engine buying you some time at the stop and go. But that is about the only difference.
Same goes with turning fans on at lower temperatures than 205 deg F. I do not want to run around on cooler days with the fans always running when they do not have to in view of my 180 deg F thermostat and in view of the 190 deg F - 200 deg F LT5 temperatures I am seeking (maybe 215 deg F on HOT 100+ deg F days).
B. What to do to keep the LT5 Cooler in Stop and Go or Long Stop Lights on HOT (100+ deg F) days..................
So....if you want to get serious ........do all the normal maintenance like clean radiator, oil cooler, and AC condenser of trash (keep the stack clean and that includes keep the stacks clean of any oil). If you want additional LT5 performance get yourself one of the Haibeck LT5 Performance Chips which turn Fans ON at 205 deg F and OFF at 200 deg F.
If you really want to get serious......install an auxiliary electric pusher fan or higher flow rate dual fans. And/or install an Aluminum After Market Radiator that offers greater cooling effect with the same coolant flow rate (but at the same time may be a bit more restrictive on the air flow rate).
If you really really want to get serious.....remove the oil cooler and AC condener. But when I am that serious I just turn AC off and if I have to .....turn the engine off.
C. Underdrive and Overdrive Water Pump Pulleys as they relate to Engine Cooling...............
Oh.....just to complete this little discussion I am having
Using a larger diameter water pump pulley (Underdrive) may buy you some engine cooling at higher RPMs if you are in the 6000-7000 rpm zone for very long where the water pump may be cavitating at that high rpms with a standard diameter water pump pulley. On the other hand, using a smaller diameter water pump pulley (Overdrive) may buy you some engine cooling at lower rpms in stop and go traffic where the coolant flow rate is normally low with a standard diameter water pump pulley.
D. Tricks to Cool the LT5 in Stop and go traffic on HOT (100+ deg F Days).
It is Ambient Temperatures of 100+ deg F that cause the LT5 Hot issues. It becomes obvious that Air Flow is the culprit in that once the ZR-1 is moving at say 20-30 mph the Coolant temperatures quickly get back in the 200 - 210 deg F range. The LT5 engine is rapidly cooled from 215+ deg F (higher if I did not turn off AC) with the ZR-1 not moving on 100+ deg F days once the Dynamic Air Flow is created by moving forward at 20-30 mph.
So the additional Air Flow required to do that (keep the engine in the 200 deg F - 210 deg F Range on a 100+ deg F day) is obviously that Air Flow hitting the front of the ZR-1 at 20-30 mph. I am thinking one can get higher pressurized Air Flow with a Pusher Fan within say 1/4 inch of the front of the ZR-1 Cooling Stack pushing Air through that stack.
1. The First Trick then since we can assume the Tony Davila Pusher Fan Solutionworks is to refine that solution such that the fix for a temporary LT5 HOT situation on a HOT day does not interfere with the normal Cooling of the ZR-1 Cooling Stack using only Stock Fans.
2. The Second Trick would be to operate that Pusher Fan(s) only when in stop and go traffic on a HOT day using a simplified Relay that can be activate remotely. The Relay wired directly from the battery to the Push Fan. No Modifications to ANY existing Electrical wiring or Electronics. This would make for a very simple and inexpensive Solution to an otherwise complicated problem
12V 15A Relay Remote Control Kit DC Connector 15 amp Heavy Duty
http://www.ebay.com/itm/Logisys-RM02-12V-15A-Relay-Remote-Control-Kit-DC-Connector-15-amp-Heavy-Duty-/380427545278?pt=LH_DefaultDomain_0&hash=item58933faabe" 3. The third Trick is to identify and control how much Air (using Stock Dual Fans or Stock Dual Fans with an Auxiliary Pusher Fan) Passes Through the AC Condenser, Oil Cooler, and Radiator rather than go around (through the gap) between the AC Condenser and Oil Cooler.....and through the gap between the Oil Cooler and Radiator. When you turn off the AC, The AC Condenser is not heating up the air passing through. The Oil Cooler is contributing (Oil Temperature Thermostat-Open-203 degree F, Fully open-266 degree F). Engine Lubrication System Functional Discussion
4. Or......install higher flow rate Puller Dual Fans replacing the Stock Puller Fans. But then we have a situation where we are pulling more air 99+% of the time when we do not have to.
Parts work together best within certain tolerances.
Heat is controlled to keep parts tolerances in the range to assure longevity.
Lubricants are designed to specification that they meet certain characteristics over a range of certain temperatures.
Fuel (gasoline) must be completely vaporized to mix with oxygen before it will burn. (liquid gasoline droplets will only burn at the surface where oxygen is present)
Operating the LT5 (or any) motor at WOT below a certain minimum temp can result in damage (refer to #s 2, 3 & 5)
Operating (any) motor where gasoline is not being vaporized completely results in carbon buildup in combustion chambers and on valves, washing the cylinder walls of needed oil, and reducing the viscosity of the oil resulting in accelerated wear of cylinder walls, bearings, and rings.
And, last, but every bit as important, in the case of the LT5, certain steps are taken in the thermostat housing (with the thermostat in place) to control coolant over-pressurization resulting from high rpm operation.
These LT5s are a magnificent engineering achievement. They are kinda rare, parts are expensive, and provide a rare experience not felt in any other Corvettes before or since. And, when operating within their "window" they are nearly "bullet proof". If you operate this or any motor outside the design window, as some always will, you're "off the chart", and serendipity becomes your tutor. (But, NOT on my dime!)
Concur with Paul....and great reasons on why to keep the thermostat at 180 deg
I run 180 deg thermostats in ALL ZR-1s.
1. At a coolant temperature of say 190 deg a 160 deg thermostat is open....so is my 180 deg thermostat. So from that point on our coolant system flow rates are identical at the same rpm. And so is the cooling.
2. Using a 160 deg thermostat in cooler weather drops the engine coolant temperature below the designed engine temperature with the 180 deg thermostat. The PVC (at the cooler engine temperatures) is working at less than optimum temperatures as well as your oil and fuel as Paul explained correctly.
Oh....almost forgot.....my fans come on a bit sooner controlled by Marc Haibeck chip to help with engine temperatures when idling at a traffic light on a hot day. But again....my 180 deg thermostat and the 160 deg thermostat are both open in that condition
But MUCH MORE as you can see asthe LT5 thermostat has several functionsLT5 Thermostats
The LT5 thermostat sits in two cavities and is located on the outlet side of the radiator. On one end of the thermostat is the first valve [pressure relief) that expands and opens to excessive radiator pressure (but only relative pressure over and above that normal thermal expansion radiator pressure). That valve is in the first cavity which is exposed to coolant outlet flow. In the second cavity is the second thermostat valve (temperature relief) which controls coolant inlet flow depending on engine temperature.
GM found at high rpm and high coolant flow, excessive pressure in the radiator, due to it's restriction, would blow the rubber seals between the side tanks and the core. GM did not want to design a specific LT5 radiator, so the solution was the radiator bypass which opens when the pressure differential across the radiator reaches a certain level. This bypass valve is part of the thermostat and, when open, allows coolant to recirculate within the engine. LT5 Coolant System Discussion
ZR1 provided this photo in the LT5 Coolant System Discussion
Lets simplify......the discussion of the 160 deg thermostat cooling better than the 180 deg thermostat.
1. Let us say we have identical radiators, identical rpm, steady state coolant temperature, and both fans on and we are cruising at same speed.
2. Lets say coolant temperature is 190 deg in both your Z and my Z given everything identical in item #1.
3. Your 160 deg thermostat is full open with same flow rate as fully open 180 deg thermostat.
4. My 180 deg thermostat is full open with same flow rate as fully open 160 deg thermostat.
5. In other words...we both have been driving our Zs for say at least 30 minutes and have reached a steady coolant state.
Now......lets say the day gets hotter. The coolant temperatures should rise the same in both your Z and my Z given EVERYTHING else is the same :p
If it gets REAL HOT......both our Zs coolant will reach 230 deg at the same time.
The maximum temperature reached (given it is over 190 deg) will be no different for you than me even though you have a 160 deg thermostat and I have a 180 deg thermostat.
I am saying that my thermostat just maintains a minimum temperature higher than yours. I am also saying your thermostat does not maintain a lower higher temperature than mine. Once both thermostats are fully open, the coolant temperatures are controlled by everything else mentioned in item #1 and not the thermostats (yours or mine).
Same goes for fans......once your fan is on and my fan which may be on at lower temperatures is on.......we have identical radiator cooling no matter how hot it gets outside.
Now if we change radiators.....you run stock radiator and I run Ron Davis....DIFFERENT STORY as I have greater dissipation of heat than you at all rpms (water pump speed dependent) and ZR-1 speeds (air flow dependent).
I would say impossible to do Camshaft Timing with engine in car but it is possible to CHECK Camshaft Timing Engine In Car. Of several 90's I have checked, none required Camshaft Timing as my LT5 engine In Car Inspection of Timing was within a couple degrees for each Camshaft.
Checking your Camshaft Timing Engine IN Car
You have to remove Cam Covers engine in car...then set up to determine or assume the current TDC timing Marks on the Harmonic Balancer are correct.
You can get close without pins in front camshaft retainers just by using a flashlight observing the pin hole in the camshaft journals alignment with the holes in the camshaft front retainers. If you want to make sure of the TDC marks on the Harmonic Balancer, you can install a dial gauge to determine when piston #1 is TDC to determine TDC easy enough engine in car and can then mark harmonic balancer and use degree tab bracket easy enough engine in car. The Tab has marks 25 deg Before and 5 deg After TDC.
You can check by rotating engine (with chain tensioners still keeping chains tight) by visual inspection in pinning holes which can be done engine in car easily. If you mess around too long especially reversing the rotation of the crankshaft, the Timing Chains will loose their hydraulic chain tensioner tension.
I set the pins in the Venier Plate slot such that the camshaft sprockets are rotated against the half moon on the camshaft (clockwise looking at front of engine) which prevents additional movement of sprockets on camshaft under any conditions. This is within 1.6 degrees of where I want the timing. See item #5c and #7a of LT5 Camshaft Timing Additional Tricks
I installed Jerry's New Dual PCV Connectors on ALL engines getting rid of all the Clap Trap Nylon Ties and Hose Clamps to keep the Old (hardened Rubber) Dual PCV connectors from slipping off the connectors or leakingHighly Recommended Right up near Top Of List with Blocking TB Coolant at each Injector Housing.
Along with the PCV Upgrades is the raised Plug Wires from Injector Housing Bolt to Plenum Bolt on ALL engines. This allows the Dual PCV Connector to be attached in front of and at the same location as the Plug Wires and above the Cam Covers.
12-13-2013, 01:20 PM
