Gear and stall reccomendation.

[Manic Machinist]

I went to a powerglide trans with a transbrake and my stall is now way too high.
I plan to use more nitrous on a regular basis and would like to get gear and stall recomendations from the experienced nitrous users.
Right now I use a 55jet in a cheater kit and want to step it up to the 83jet.
I have a Coan 8" steel stator converter and a 434sbc with 13.6-1, cnc ported AFR220's, glide with 1.80 straight cut gears, and 4.33 rear gear.
Right now the converter flashes to 5800rpm's and I shift around 6500. The motor comes down to 6000 at the shift. The car weighs about 3200 with driver.
How much of a power band should I have with this set-up? 6 or 700 rpm seems very narrow. The car runs 6.15-6.20 on a hot, humid night with the current set-up(55 nitrous jet) at 111-112mph.
Thanks for any guidance.

[Manic Machinist]

Im using a 7AL-3 with a 3600 rpm launch chip in it. When I let off the transbrake, rpm's go to 5800.

[Mike Thompson]

That doesnt sound to bad to me. Maybe a 9 inch converter at 5500 would be a little better. My 8 inch never did well with nitrous. Can you shift it higher than 6500 or does it slow down?

[partywagon]

The converter is way too loose ,my car drops 2000 rpm on the shift on a 650 shot
my car had a 9.5" PTC converter .7500 to 5500 or so
I just had a customer that had a 8" converter and was doing the same thing, I change it to a 9" the converter change went from 6.18 to 5.84.
About the gear! What gear do you run now ? Tire? weight?

[Manic Machinist]

Partywagon, im using 29.5 x 10.5 stiff side wall tires. The gear is 4.33, and the car weighs about 3200lbs w/driver.

As far as shifting higher, the motor is done by 6500-6600.
Thanks again guys.

[partywagon]

I would try to get a different converter like you said you are only have a 6 or 700 rpm power band. If (when) you jet up it will not get any better !

Chris

[superdave]

u should be in the fives no doubt with a 434 on gas.....
i bet the 60' is not picking up either on the juice?...what's it run on motor....?
you are freewheelin' that 8" thru the roof.....

you should pick up at least 5 tenths on a 250- shot minimum if it's a nitrous combination...that's working

if not..i'd burn it-

i sent you a pm about my 9"...


my combo 421sbc, 2 stages, 2975lbs w/driver, 4.56 gear,31X10.5X15w, 1/8 mile, p-glide, 4000 stall on motor