LS400 Supercharger Project
#76
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After checking the engine today I have found many vacuum leaks that are causing an extremely high and unstable idle. I have removed the manifold and blower to make sure I have enough gasket material for any possible leak points.
Also the rear intake was a little unlevel where I installed the Idle air control valve and I found out that I cracked it in 2 pieces when I torqued it down. I will superglue it together and gasket the hell out of it.
The 3 bolts that hold down the supercharger even had vacuum leaks, so now I have to just put everything back together very cautiously.
I am running lean due to the extra air being sucked in, however at higher revs it smooths out nicely.
Also the rear intake was a little unlevel where I installed the Idle air control valve and I found out that I cracked it in 2 pieces when I torqued it down. I will superglue it together and gasket the hell out of it.
The 3 bolts that hold down the supercharger even had vacuum leaks, so now I have to just put everything back together very cautiously.
I am running lean due to the extra air being sucked in, however at higher revs it smooths out nicely.
#79
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After checking the engine today I have found many vacuum leaks that are causing an extremely high and unstable idle. I have removed the manifold and blower to make sure I have enough gasket material for any possible leak points.
Also the rear intake was a little unlevel where I installed the Idle air control valve and I found out that I cracked it in 2 pieces when I torqued it down. I will superglue it together and gasket the hell out of it.
The 3 bolts that hold down the supercharger even had vacuum leaks, so now I have to just put everything back together very cautiously.
I am running lean due to the extra air being sucked in, however at higher revs it smooths out nicely.
Also the rear intake was a little unlevel where I installed the Idle air control valve and I found out that I cracked it in 2 pieces when I torqued it down. I will superglue it together and gasket the hell out of it.
The 3 bolts that hold down the supercharger even had vacuum leaks, so now I have to just put everything back together very cautiously.
I am running lean due to the extra air being sucked in, however at higher revs it smooths out nicely.
I'd recommend epoxy over superglue--much stronger, and not as brittle. Superglue has good shear strength, but terrible tensile strength.
What is your plan for sealing the bolt leaks--rtv?
#81
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I just put everything back together and made sure there was no leaks, now I have a stable idle but it is way to high....
In park it goes up to 2800 and steady
In drive or reverse it drops down to a steady 1100
I am getting good readings from the wideband at idle 14.6-15.2
When I drove it I could just let off the brake and the car would accelerate up to 20MPH, and when I step on it just bogs down.
I will check the Throttle position sensor 2morrow.
In park it goes up to 2800 and steady
In drive or reverse it drops down to a steady 1100
I am getting good readings from the wideband at idle 14.6-15.2
When I drove it I could just let off the brake and the car would accelerate up to 20MPH, and when I step on it just bogs down.
I will check the Throttle position sensor 2morrow.
#82
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Ignore the last post...I reset ECU overnight, topped off all fluiuds, reinstalled the cruise, trans, and accelerator pedal cables... Tightened down all hose clamps and reset dashpot setting and adjusted throttle opener.
I now have a perfect idle at about 14.7-15.2, but I am still suffering from a hesistation at kickdown. I have not had a chance to drive it yet since I fixed whatever was wrong; however I got the chance to go back and forth in the driveway. I plan on filling up the tank as well since that gas has been there since May. I also have to make a new spacer for the timing belt pulley I used for my setup. It is starting to tilt on its axis and causing the belt and tensioner to slip.
Other then that I feeling a lot better about everything today. Once I drive it I will have a better feel about the hesitation.
I now have a perfect idle at about 14.7-15.2, but I am still suffering from a hesistation at kickdown. I have not had a chance to drive it yet since I fixed whatever was wrong; however I got the chance to go back and forth in the driveway. I plan on filling up the tank as well since that gas has been there since May. I also have to make a new spacer for the timing belt pulley I used for my setup. It is starting to tilt on its axis and causing the belt and tensioner to slip.
Other then that I feeling a lot better about everything today. Once I drive it I will have a better feel about the hesitation.
#83
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Congrats on getting a good idle.
As for the gas, May isn't too bad, but gas does lose octane rating as it sits. To be safe, esp since you're running boost, put in some octane booster as you fill it up with the highest octane gas you can get your hands on (I know Michigan has 94 at the pumps, not sure about TX).
Obviously you won't be needing to run high octane once you use up your current tank.
A cheaper alternative to the expensive and not-so-effective off the shelf octane boosters is adding toluene to the tank. I do that for a high boost motor after the gas in the tank has been sitting over the winter.
As for the gas, May isn't too bad, but gas does lose octane rating as it sits. To be safe, esp since you're running boost, put in some octane booster as you fill it up with the highest octane gas you can get your hands on (I know Michigan has 94 at the pumps, not sure about TX).
Obviously you won't be needing to run high octane once you use up your current tank.
A cheaper alternative to the expensive and not-so-effective off the shelf octane boosters is adding toluene to the tank. I do that for a high boost motor after the gas in the tank has been sitting over the winter.
#84
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I have everything up and running pretty much as it should. I finally got the boost gauge working and I have found out that as soon as the bypass valve shuts close and the blower starts making boost it just bogs down. I can hear ther blower getting that whine, but it just bogs down, the wideband starts working its way to around 13.0 but then just goes all the way back to (air) ---.
My plugs are NGK coppers gapped at .035
Stock wires, stock intake, all ignition parts were in good shape and resistance.
The blower will need to be rebuilt, but should not be the culprit. Belt slip may cause this, however I have the same setup as so many others and my tensioner does shake a little but marks right where it should.
What do you think????
My plugs are NGK coppers gapped at .035
Stock wires, stock intake, all ignition parts were in good shape and resistance.
The blower will need to be rebuilt, but should not be the culprit. Belt slip may cause this, however I have the same setup as so many others and my tensioner does shake a little but marks right where it should.
What do you think????
#87
ok, yes. --- is very very very very lean.> But, not to worry as you state it's deceleration.
Where is your AFR under full throttle from 2000rpm > 6000rpm?
Any readings or datalog you can post up?
Where is your AFR under full throttle from 2000rpm > 6000rpm?
Any readings or datalog you can post up?
#88
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I can not get any reading under full throttle.... At WOT the bypass valve shuts and the blower starts making boost. At that time the engine bogs down. No knocking that I know of and no check engine light.