Converter feed restriction
Thread Starter
Teching In
Joined: Jun 2023
Posts: 4
Likes: 1
Converter feed restriction I have a th 400 behind a decent Lq4 6.0.
Im having it out for rebuild since I never liked its behavior. I may upgrade hp later so lets say trans needs god for 650 hp.
I have three options on pump boost spring.
yellow unknown but pretty sure its a transgo spring
orange transgo spring
oem blue spring with one or two horseshoe shims
Its geting dual feeded
checking all clearances
high energy frictions
alu pistons
hold gear at any rpm mod
B&M shift kit plate
Mostly street maybe some strip
wich spring Do you recomend? and should I restrict the converter feed? Some says both I ways are ok? But a .120” hole is safe?
Im having it out for rebuild since I never liked its behavior. I may upgrade hp later so lets say trans needs god for 650 hp.
I have three options on pump boost spring.
yellow unknown but pretty sure its a transgo spring
orange transgo spring
oem blue spring with one or two horseshoe shims
Its geting dual feeded
checking all clearances
high energy frictions
alu pistons
hold gear at any rpm mod
B&M shift kit plate
Mostly street maybe some strip
wich spring Do you recomend? and should I restrict the converter feed? Some says both I ways are ok? But a .120” hole is safe?
TECH Resident
Joined: May 2006
Posts: 969
Likes: 119
If you want to make sure that the torque converter does not push forward and take out the thrust bearing in the motor. On the input shaft, grind off two splines a 180 degrees apart from each other. GM knew about the possibility of this happening back in 1970. It is very rare to see one of these oem shafts have these. I discovered this way back in 1980 and contacted John Kilgore about what I had seen and thought about this problem. He verified that GM knew about this and this was the solution at that time. As long as the problem is solved using a restrictor or grinding off the two input shaft lands, your choice.
The Yellow spring from TransGo (highest line pressure) is what I have seen used in Trans brake setups. The Orange spring from TransGo is what I used in all of my Street Strip builds.
The Yellow spring from TransGo (highest line pressure) is what I have seen used in Trans brake setups. The Orange spring from TransGo is what I used in all of my Street Strip builds.
Thread Starter
Teching In
Joined: Jun 2023
Posts: 4
Likes: 1
If you want to make sure that the torque converter does not push forward and take out the thrust bearing in the motor. On the input shaft, grind off two splines a 180 degrees apart from each other. GM knew about the possibility of this happening back in 1970. It is very rare to see one of these oem shafts have these. I discovered this way back in 1980 and contacted John Kilgore about what I had seen and thought about this problem. He verified that GM knew about this and this was the solution at that time. As long as the problem is solved using a restrictor or grinding off the two input shaft lands, your choice.
The Yellow spring from TransGo (highest line pressure) is what I have seen used in Trans brake setups. The Orange spring from TransGo is what I used in all of my Street Strip builds.
The Yellow spring from TransGo (highest line pressure) is what I have seen used in Trans brake setups. The Orange spring from TransGo is what I used in all of my Street Strip builds.
Been told orange spring is to much for my trans and that Ishould use a oem blue with two horseshoe shims for 170-175 psi?
TECH Junkie
Joined: Dec 2012
Posts: 3,614
Likes: 1,326
From: Iowa
You've gotten solid advice on yellowbullet already
Yes just use a restrictor....the sizing recommended there is good
An no you do not need any stiffer spring than stock.
A stock spring with either 1 or 2 horseshoe shims will be PLENTY for your 650hp setup.
Also, don't use that B&M plate.
Just use the stock plate and modify it to your liking for shift firmness.
Yes just use a restrictor....the sizing recommended there is good
An no you do not need any stiffer spring than stock.
A stock spring with either 1 or 2 horseshoe shims will be PLENTY for your 650hp setup.
Also, don't use that B&M plate.
Just use the stock plate and modify it to your liking for shift firmness.
Thread Starter
Teching In
Joined: Jun 2023
Posts: 4
Likes: 1
You've gotten solid advice on yellowbullet already
Yes just use a restrictor....the sizing recommended there is good
An no you do not need any stiffer spring than stock.
A stock spring with either 1 or 2 horseshoe shims will be PLENTY for your 650hp setup.
Also, don't use that B&M plate.
Just use the stock plate and modify it to your liking for shift firmness.
Yes just use a restrictor....the sizing recommended there is good
An no you do not need any stiffer spring than stock.
A stock spring with either 1 or 2 horseshoe shims will be PLENTY for your 650hp setup.
Also, don't use that B&M plate.
Just use the stock plate and modify it to your liking for shift firmness.
.120” hole drilled in the setscrew?
I dont have a stock plate, what dont you like with the B&M plate? Some says its ok?
