Yeah how would this be? I thought t/h only changed the TCM?? Can you shed some light Mike?
Allison 5sp: How to make a high HP allison live???
- Thread starter Righteyeblind
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Yeah how would this be? I thought t/h only changed the TCM?? Can you shed some light Mike?
Doesn't the converter flow valve/ knockdown valve eliminate the pressure decrease when the converter clutch is applied be it T/H or O/D?
Pressure knockdown occurs anytime the converter clutch applies and is controlled by the converter flow valve. When TCC hits, the converter flow valve strokes and sends pressure to partialy block the pressure regulator valve and restrict mainline pressure. The Transgo valve partialy eliminates some of the knockdown but not all of it.
Leaving the ball out and replacing the spring with a longer one will eliminate knockdown.
The reason for the longer spring is to take up the space the missing ball left and not allow the valve to free float.
Leaving the ball out and replacing the spring with a longer one will eliminate knockdown.
The reason for the longer spring is to take up the space the missing ball left and not allow the valve to free float.
I don't have any springs as I don't use the Transgo valve. Hardware store should have what you need.
Awesome info thanks remember the size of the spring if not ill just figure it out
:thumb:
I've had the checkball out of my converter valve for about 50k miles, and I have noticed no ill effects. It really doesn't run any hotter than it did before as far as I can remember. I've never seen it over 200 degrees, and cruising on the highway, it's usually around 150. It really only gets hotter if I'm doing a lot of stop and go in town driving.
Is a billet C2 hub or billet planet necessary also? If not both. I had one twist the splines twisted off once but thought it might be a fluke. Also didnt want to spend another $1200 at the time.
my opinion is no, a sleeved hub holds up pretty darn well. i can show you pictures of my sleeved hub taking a beating when i twisted the splines on my planet. the hub was totally reusable and the splines only had a slight bow to them, but not enough to impede engagement. it's cheaper to replace as well when a tie up still happens down the road due to clutch wear or anything...whereas the billet parts can still break hard parts in your trans during a tie up and cost you more. I don't mind having a cheap and easy to fix weak link at this point.
I've had 3 sleeved hubs jump the splines. I have since had billet hubs made. Between my hub and my billet planet, I have not seen a failure. The SC sleeved hub is a nice unit and strong, but will not stand up to bad tuning.
Is the valve real fussy when it comes to spring rate. What are the side effects of finding a spring alittle stiffer or alittle softer to replace the transgo one with?
Alright well I just did a pressure test.
First started-280 psi in park at idle
Warm-250 psi in park at idle
Put in drive no throttle-150psi
Give a little bit of throttle in drive with the brakes on 280psi
This seems good doesnt it?
I Borrowed a tech 2, anything I can check with it?
First started-280 psi in park at idle
Warm-250 psi in park at idle
Put in drive no throttle-150psi
Give a little bit of throttle in drive with the brakes on 280psi
This seems good doesnt it?
I Borrowed a tech 2, anything I can check with it?
are your transgo springs for C1 the old style (2 different spring rates) or the new style (all the same spring rate)?
You're talking about the C2 return springs. The reason the eartly springs had 2 different rates is because someone accidently ordered the wrong springs and the spring company would not take them back. So Transgo had to order another set of springs and stagger them to get the rate they wanted. When they ran out of the staggered springs they ordered thecorrect springs. The rate were identical between the eary and late springs.
Thanks Mike, damn fat fingers I have. I was under the impression that the new springs equated to overall more consistent pressure...
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