Stall speed problems on the line with 63 turbo

[randymc1]

The 63 with the pte houising doens't seem to take flight till 3900 rpms.Does that seem right? I could be running to rich causing to further slow stall? I have tried 2 converters and still haven't got off the line with any boost. I have a precision 3200 and a custom built 3000 stall converters. Neither is near loose enough I guess. I am running a th400 with a manual vavle body. The th400 could be part of the problem with a ? on the first gear ratio. I am guessing a 2:54 first gear. A tranny guy at our shop said it looked like a early 70 cadillac tranny. I assume a need a looser torque converter and whould like to have the precision converter loosened. How much I wonder? How much to change 1st gear to 2:75 ratio?
Frustrated Randy

 

[sixgun86gn]

I have that setup and it spools like mad.You might try leaning it out just a little.My fuel pressure is set at 39# with the line on.I have the 3200 stall vigilante and it spools fast even from a roll.

 

[Reggie West]

Two things.

Less fuel at lower rpms.

Try increasing the timing on the low end that will help spool up .

 

[Steve Hill]

heat energy is what spools that turbine wheel. If you can't get it up (heh heh) by 3900 something is amiss.
Are you using a w-a system? You don't mention it but if so that could be a big factor.
Somehow you should try to figure out your f/a ratio.
As Reggie suggests you are likely too rich. Because by 3900 *something* should be happening ;-)

 

[Hawaiian Turbo]

I thought DECREASING timing helped spool up.

 

[jastrckl]

decreasing timing (retarding) increases spool, since more fuel burns in the exhaust the more you retard the timing, which creates more energy in the exhaust.

 

[wagon]

Try putting your air cleaner outside of the engine compartment. It's still behind the radiator support, isn't it? That would be my guess.

Brian

 

[StageII86]

As far as timing goes in relation to spool, I've gathered that unless you can eliminate almost ALL of the timing (like w/ a box), to actually burn the majority of the mixture in the exhaust port, more timing and a leaner (more "NA" power) spool up curve work better. On a fast system i tried taking the spool up curve timing down from in the 40's to the low 20/high teens and it lost spool up speed. However, cars with boxes that take it down to somewhere like zero deg. when they are on the tranny brake spool instantaneously. I may be wrong, but this is just what I've SEEN on a few different cars.

 

[Two Lane]

VERY EDUCATIONAL THREAD

Originally posted by StageII86
As far as timing goes in relation to spool, I've gathered that unless you can eliminate almost ALL of the timing (like w/ a box), to actually burn the majority of the mixture in the exhaust port, more timing and a leaner (more "NA" power) spool up curve work better.

Cars with boxes that take it down to somewhere like zero deg. when they are on the tranny brake spool instantaneously.

I may be wrong, but this is just what I've SEEN on a few different cars.

VERY Interesting! Great points to consider!

 

[Steve Hill]

STAGEII86 is right about the timing.
Because you have to retard the timing so far to get the heat, you wind up with other issues.
Just lean out the mix on the bottom and you'll get the desired result.

Also, WAGON offers a nice tip on the air cleaner sucking hot engine air. Might not be the problem but we've seen this b4.

 

[Hawaiian Turbo]

I took out 6 degrees with my trans-plus when I installed the 63-1, and I could feel the difference, less lag.

 

[Steve Hill]

was your base timing retarded by that amount for the entire rpm band? If so that is impressive hp for stock heads/cam.

 

[Hawaiian Turbo]

No, I put the timing back in above 3500 RPM.

 

[Steve Hill]

didn't know you could do that with the Trans+.
That's cool. And, apparently, works well for you.
From my experience the more you advance total timing the more power you'll make....

 

[TurboDave]

Recucing timing to aid spool is an old trick, first brought to light with the Thrashers

The thing is, you can't just retard timing and hope for the best. The fuel down there can't be too rich.

I've tried this on my Translator + to prove the point and it works wonders. Just pulling out as little as 8º down in the "under 3400 rpm" band got the turbo to spool on tracks where it was a problem (high density altitude).

 

[Steve Hill]

So, can you do the same trick with fueling as with timing? I.E. lean it out for a certain rpm band?
Lots of neat tricks, that Trans+ does ;-)