formula355LT1

I'm told that on 93-95 OBD1 LT1's you cant go past a 3000 stall or it will have problems shifting correctly. I want to get a 4000-4400 in my car, and I was wondering if I went with a Manual Valve Body would I be able to go with the bigger stall since it would no longer be cpu controled(i think) or would there still be problems? THANKS

2xLS1

iTrader: (25)

It is fixable in the PCM calibration. You just need to edit the VSS diagnostic enable paramater to a value higher than the stall speed of the converter..

formula355LT1

ok thanks, i'm going manual valve body anyways though...(i'm having my trans rebuilt too), so do i still have to change this stuff in the PCM? or can i just leave it alone?

jimbob

iTrader: (4)

Can't tell you about the manual shift body but, I can tell you that manually shifting a normal body didn't work...With that tight converter you probably won't have an issue anyways!

95ttoplt1

iTrader: (3)

I was able to fix this with my car, there are many ways o do from what I have read but mine was very easy just changed the 1-2 shift MPH.

Apparently the stock output shaft is very weak and with a hard launch the PCM loses the VSS signal due to output shaft flex.

But thats just a theory.

performabuilt

iTrader: (25)

I have never heard of that, interesting were you losing your speedo signal during a hard launch mph 0 ? I have heard of a few people having that issue but cant think of any mechanical or electrical reason it should happen and I dont think it should because it only happens to a few people here and there across multiple model years.

95ttoplt1

iTrader: (3)

That was the explaination I got as to why the "stall wall" occurs. I set my 1-2 shift mph to 1 and shift on rpm and haven't had a problem.