HELP!!! 90/90 change gone awry??
Have you got it tuned for the 90/90 swap yet? I might be wrong but I believe you have to get the car retuned for the new intake and TB. The computer can't just learn this change compared to going from a stock TB to a ported TB. Let us know what you figure out!
John
John
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From: Paxs River, MD
Originally Posted by JohnJanz@Texas-Speed
Have you got it tuned for the 90/90 swap yet? I might be wrong but I believe you have to get the car retuned for the new intake and TB. The computer can't just learn this change compared to going from a stock TB to a ported TB. Let us know what you figure out!
John
John
Originally Posted by shooter
Now I've heard that F.A.S.T T/B have had problem in the pass and have had to be sent back for rework could this be the problem???
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From: Paxs River, MD
Originally Posted by 99blancoSS
I thought the FAST thing was a sticky return spring or something like that
Originally Posted by shooter
I've talked with several people that have done swap, wrote that question on the board and was told the tune can wait until I do my heads and cam swap that I'm going to get from you guys.
You shouldn't be running that crappy w/o a tune. It sounds like something else isn't right like a vacuum leak or a sensor not plugged in maybe. I didn't change my tune at first when I put my 90/90 on and I wasn't running badly at all. Now I do have more mods/cam/etc but I can't imagine the tune getting that f-ed up just from an intake/tb. As mentioned you can pull a plug to see if it's running super rich. I would expect it to be leaner now that you're sending more air in anyways.
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From: Paxs River, MD
Originally Posted by Red99TA
You shouldn't be running that crappy w/o a tune. It sounds like something else isn't right like a vacuum leak or a sensor not plugged in maybe. I didn't change my tune at first when I put my 90/90 on and I wasn't running badly at all. Now I do have more mods/cam/etc but I can't imagine the tune getting that f-ed up just from an intake/tb. As mentioned you can pull a plug to see if it's running super rich. I would expect it to be leaner now that you're sending more air in anyways.
Thank-you agian for all the input.
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Car does not need a tune unless you are running a vette drive by wire throttle system. The F-body cable system take the needing a tune out of the equation.
FAST90/90 on an F-body= No tune needed to run
FAST90/90 on a throttle by wire system like the vettes = Tune needed
FAST90/90 on an F-body= No tune needed to run
FAST90/90 on a throttle by wire system like the vettes = Tune needed
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From: Paxs River, MD
Originally Posted by brad8266
Car does not need a tune unless you are running a vette drive by wire throttle system. The F-body cable system take the needing a tune out of the equation.
FAST90/90 on an F-body= No tune needed to run
FAST90/90 on a throttle by wire system like the vettes = Tune needed
FAST90/90 on an F-body= No tune needed to run
FAST90/90 on a throttle by wire system like the vettes = Tune needed
The throttle body should be even with the intake. If you used the FAST gasket for the TB, then it is very stiff and likely can't be fully compressed as only 50% of the o-ring fits in the groove of the intake. A face seal needs about 20%-30% compression, or in this case 0.028-0.041" of compression. If you tighten it evenly, you will have a gap all the way around and it should be even. I did mine last night on the work bench (a definite advantage) and have 0.016" gap all the way around. Tony Mamo mentions this in his instructions, overtightening can damage the ears on the intake where the TB attaches. Also, if yours is noticably uneven, there may be a leak source there.
On the intake itself, did you use the FAST gaskets? The stock GM gaskets don't work to well from what I have read, especially if re-used. How tight did you go and did you go slowly in steps? This manifold appears to be more flexible than the stock unit and not going slowly in steps can lead to a leak. From the sounds of things, you may have a leak that is messing things up.
Very interested in any lessons learned you have.
On the intake itself, did you use the FAST gaskets? The stock GM gaskets don't work to well from what I have read, especially if re-used. How tight did you go and did you go slowly in steps? This manifold appears to be more flexible than the stock unit and not going slowly in steps can lead to a leak. From the sounds of things, you may have a leak that is messing things up.
Very interested in any lessons learned you have.
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From: Paxs River, MD
Originally Posted by 99blancoSS
Silly question but did you forget to put the pcv back in or get in in backwards?
I think I'm going to yank it off and go back to stock and see what happends.
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From: Paxs River, MD
Originally Posted by 99blancoSS
Silly question but did you forget to put the pcv back in or get in in backwards?
Originally Posted by shooter
actual this may be a good point backwards?? how would I know??
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From: Paxs River, MD
Originally Posted by 99blancoSS
Good question. I'll have to go rip it out and see what it looks like to be able to tell which end goes where. Its a new pvc right? It isnt clogged is it?
clogged not sure but i only have 28k miles on the car.
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From: Paxs River, MD
Originally Posted by sidewayz28
after i swapped heads and 90/90 my car doesnt find its idle unless i help it, usually just surges until it warms up a bit, but nothing major. its probably just the tune