Supercharger/Tranny issues
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Joined: Dec 2000
Posts: 1,320
From: Alta Loma, CA
Re: Supercharger/Tranny issues
Originally Posted by Kevin Blown 95 TA
Transgo makes it.
Have you ever met ANYONE who can give a decent explanation of the pressure offset tables in an A4 PCM??? My trans seemed to be doing fine with my computer tuned pressures, but I was never comfortable with them. Jury's still out on the modulator/check valve mod, but I got that clue from some guy who built trannys and raced alot - he was on the LT1 Edit list along with some really knowledgable pioneers of LT1 PCM hacking.
Have you ever met ANYONE who can give a decent explanation of the pressure offset tables in an A4 PCM??? My trans seemed to be doing fine with my computer tuned pressures, but I was never comfortable with them. Jury's still out on the modulator/check valve mod, but I got that clue from some guy who built trannys and raced alot - he was on the LT1 Edit list along with some really knowledgable pioneers of LT1 PCM hacking.
So, when I get blown, I will need a check valve to compliment this? Also, would it just be better to ditch the vacuum assist and get a programmer from TCI to control the trans pressure? How is the TCI unit integrated with the factory PCM?
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Joined: Oct 2001
Posts: 2,684
Re: Supercharger/Tranny issues
Originally Posted by snorkelface
When my transmission was installed, the fed a vacuum lead from the intake to the trans. I imagine this is the vacuum mod you are referencing?
So, when I get blown, I will need a check valve to compliment this? Also, would it just be better to ditch the vacuum assist and get a programmer from TCI to control the trans pressure? How is the TCI unit integrated with the factory PCM?
So, when I get blown, I will need a check valve to compliment this? Also, would it just be better to ditch the vacuum assist and get a programmer from TCI to control the trans pressure? How is the TCI unit integrated with the factory PCM?
The TCI controller for $700 will plug into the transmission & control the shifts & pressure and if you had that goofy 1-3 shift messin with ya at the track when you get a good 1.7 60 then it would get rid of that, too, but if you can program the shift points, and the vacuum modulator takes care of the pressures, then you're good to go unless you have that 1-3 shift problem in which case you need to get PCM4less or Ed Wright to fix it for you. Otherwise buy the $700 TCI if you want and let it do the work.
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Joined: Jan 2006
Posts: 9
Re: Supercharger/Tranny issues
Originally Posted by blown94
a 383 LT1 made 622 rwhp with 4 lbs. of boost???? How in the hell is that possible.
Anyways, since yer 1-2 shift is good that rules out the EPC being bad. You could however have a bad accumulator thats just leaking pressure off. Unfortunately its the accumulator under the valve body. If you feel confident, take the V.B. down and check out the accum. in the case side. Sometimes stupid people use plastic accumulators which break. Im leaning more towards the 3-4 piston seal is ripped. Prolly snagged it during assembly or they re-used a bonded piston they "thought" was good.
Anyways, since yer 1-2 shift is good that rules out the EPC being bad. You could however have a bad accumulator thats just leaking pressure off. Unfortunately its the accumulator under the valve body. If you feel confident, take the V.B. down and check out the accum. in the case side. Sometimes stupid people use plastic accumulators which break. Im leaning more towards the 3-4 piston seal is ripped. Prolly snagged it during assembly or they re-used a bonded piston they "thought" was good.
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Joined: Dec 2000
Posts: 1,320
From: Alta Loma, CA
Re: Supercharger/Tranny issues
Originally Posted by Kevin Blown 95 TA
The check valve goes in the same vacuum line and it lets the boost out so your tube won't blow off or you won't rupture the diaphragm in the modulator.
The TCI controller for $700 will plug into the transmission & control the shifts & pressure and if you had that goofy 1-3 shift messin with ya at the track when you get a good 1.7 60 then it would get rid of that, too, but if you can program the shift points, and the vacuum modulator takes care of the pressures, then you're good to go unless you have that 1-3 shift problem in which case you need to get PCM4less or Ed Wright to fix it for you. Otherwise buy the $700 TCI if you want and let it do the work.
The TCI controller for $700 will plug into the transmission & control the shifts & pressure and if you had that goofy 1-3 shift messin with ya at the track when you get a good 1.7 60 then it would get rid of that, too, but if you can program the shift points, and the vacuum modulator takes care of the pressures, then you're good to go unless you have that 1-3 shift problem in which case you need to get PCM4less or Ed Wright to fix it for you. Otherwise buy the $700 TCI if you want and let it do the work.
I don't have the 1-3 shift problem now, but maybe I will when my horsepower is tripled!
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