procharged 4l80e
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I have a 490 BBC with a procharger f1 with 18psi right now looking for 20-22 this sat. On dyno ( STREET DRIVEN)
I have a locally built race 4l80e. Full manual, vacuum controlled line pressure
We notice last weekend the tranny pan was leaking pretty good when we under a full run on the dyno
The vacuum line runs from the throttle body to the tranny and in-between the two there is a 3/8 t fitting that has a check valve so the boost pressure supposable don’t pressurize the tranny is that 3/8 line big enough to let out 18psi let alone 20ts I thought about putting two check valves in but I also do not want to lose boost through them how ever much would go through two 3/8 holes
If it is pressurizing the tranny can I delete the vacuum line completely or will it hurt the tranny some how street driving or racing the truck thanks for any advice
I have a locally built race 4l80e. Full manual, vacuum controlled line pressure
We notice last weekend the tranny pan was leaking pretty good when we under a full run on the dyno
The vacuum line runs from the throttle body to the tranny and in-between the two there is a 3/8 t fitting that has a check valve so the boost pressure supposable don’t pressurize the tranny is that 3/8 line big enough to let out 18psi let alone 20ts I thought about putting two check valves in but I also do not want to lose boost through them how ever much would go through two 3/8 holes
If it is pressurizing the tranny can I delete the vacuum line completely or will it hurt the tranny some how street driving or racing the truck thanks for any advice
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Do you have an actual check valve or the little bleed off check valve from transgo? I thought about installing a reagular check valve. After testing the check valve, once you pull a vaccum on the check vavle, you keep a vaccum on it. The valve checks back to the engine and once your in boost the vaccum is held in by the check. I ordered the accual check valve from trans go whick is basically a ball that checks under vaccum, but releases to the atmosphere under boost. If that makes sense. ??
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i kind of wondered about using a ck valve on a vac mod., because the mod would keep seeing the vac, because the ck valve would hold it-makes sense if there was some way to release it
on my turbo 400, i use the vac mod w/o a ck valve, and seems to work fine-how much boost it can take not sure, i have run 14 lbs w/o a problem, and in the past run over 20 on another one-i remember, B & M i think, used to offer a mech mod for boosted engines
getting ready to do a man. 4l80e, so im curious how you make out using the valve
on my turbo 400, i use the vac mod w/o a ck valve, and seems to work fine-how much boost it can take not sure, i have run 14 lbs w/o a problem, and in the past run over 20 on another one-i remember, B & M i think, used to offer a mech mod for boosted engines
getting ready to do a man. 4l80e, so im curious how you make out using the valve
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the transgo check valve actually has a ball in it
the design of the check valve is a BIG T. the t is upside down and the ball is in the top vacuum holds the ball closed (down) and under boost it pushes up to serten point to let the pres. out but I do not know if the one is enough for my 18psi now and 20-22 later
the design of the check valve is a BIG T. the t is upside down and the ball is in the top vacuum holds the ball closed (down) and under boost it pushes up to serten point to let the pres. out but I do not know if the one is enough for my 18psi now and 20-22 later