How to properly set up a Boosted TH400/LSx?
08-10-2013, 01:14 PM
#1
How to properly set up a Boosted TH400/LSx? I have a few questions that I can't seem to find answers to by searching. So I'm hoping some of you guys can help me out here and leave some answers for the future Searchers. 
I'm running a Twin Turbo 404 ci LS2 with a full Auto forward TH400. Yank 3600 Stall. Internals unknown. I want to keep the automatic shifting feature as this is a street car. But I want to set this combo up right, and to it's fullest potential when time comes for track days and spirited runs. So here goes...
Currently, the trans is running the Vac modulator with NO check valve. Shifting works ok while cruising around. It will shift real early in "Drive" when I go to WOT.
1. CHECK VALVES
Where can these Boost "Check Valves" be located? (who sells them?) Are these check valves made specifically for this purpose? Or are they regular ol' check valves?
2. Kick down cables. Are you guys running these on your Turbo/Supercharged applications? I understand that Manual VB's don't apply here. What about the full auto guys? Is there a need for this, and what are the Pros and Cons of having this hooked up?
I'd like to get this combo set up the right way. Any recommendations would be greatly appreciated!
I'm running a Twin Turbo 404 ci LS2 with a full Auto forward TH400. Yank 3600 Stall. Internals unknown. I want to keep the automatic shifting feature as this is a street car. But I want to set this combo up right, and to it's fullest potential when time comes for track days and spirited runs. So here goes...
Currently, the trans is running the Vac modulator with NO check valve. Shifting works ok while cruising around. It will shift real early in "Drive" when I go to WOT.
1. CHECK VALVES
Where can these Boost "Check Valves" be located? (who sells them?) Are these check valves made specifically for this purpose? Or are they regular ol' check valves?
2. Kick down cables. Are you guys running these on your Turbo/Supercharged applications? I understand that Manual VB's don't apply here. What about the full auto guys? Is there a need for this, and what are the Pros and Cons of having this hooked up?
I'd like to get this combo set up the right way. Any recommendations would be greatly appreciated!
Last edited by BlwnLs1GTO; 08-10-2013 at 02:05 PM.
08-14-2013, 01:29 PM
#5
From what ive been told when researching my 400 setup was that its better to use the Trans go reprogramming kit to run full manual. You can run a series of a couple of the bleed off valves trans go sells to run full auto but with high boost ie over 15psi Im not sure it works that well, over 8psi you have to run 2 or more of them to bleed off boost fast enough. There is no kick down cable on a 400, its electronic. It uses a switch that needs to be pressed in by the gas pedal and then will kick down 3-2.
08-14-2013, 05:59 PM
#7
Thank you. It seems most run the FMVB on this type of setup. I've been running around with the Auto feature, It I just figured I could get the Check valves installed, dial in the Vac Mod. along with the kickdown and be good to go. Oh well. Thanks for the info.
Trending Topics
08-14-2013, 08:22 PM
#8
You can use auto feature with big power in a TH400 but the hydraulics need to be properly setup. Most shops don't understand the hydraulics and assume they must use a manual valve body. A manual valve body is "easier" for them. Most FMVB's change NOTHING except force the VB to be manually shifted. The shift valves still move, everything in the VB is still active, fluid still flows the same way. So that's not a magical improvement and no reason an auto shifted VB can't do it as well.
08-15-2013, 12:31 PM
#9
TransGo makes the check valves you need specifically for your purpose. You will likely need to put two in line.
You can use auto feature with big power in a TH400 but the hydraulics need to be properly setup. Most shops don't understand the hydraulics and assume they must use a manual valve body. A manual valve body is "easier" for them. Most FMVB's change NOTHING except force the VB to be manually shifted. The shift valves still move, everything in the VB is still active, fluid still flows the same way. So that's not a magical improvement and no reason an auto shifted VB can't do it as well.
You can use auto feature with big power in a TH400 but the hydraulics need to be properly setup. Most shops don't understand the hydraulics and assume they must use a manual valve body. A manual valve body is "easier" for them. Most FMVB's change NOTHING except force the VB to be manually shifted. The shift valves still move, everything in the VB is still active, fluid still flows the same way. So that's not a magical improvement and no reason an auto shifted VB can't do it as well.
So do you think I can get away with the Auto feature if I put in a couple of these check valves and set up the kick down cable?
Or would I need to order a valve body from you that is set up specifically for this purpose?
Thanks again.
08-15-2013, 02:46 PM
#10
Thank you very much, Jake. And others who've responded.
So do you think I can get away with the Auto feature if I put in a couple of these check valves and set up the kick down cable?
Or would I need to order a valve body from you that is set up specifically for this purpose?
Thanks again.
So do you think I can get away with the Auto feature if I put in a couple of these check valves and set up the kick down cable?
Or would I need to order a valve body from you that is set up specifically for this purpose?
Thanks again.
