i went to the track last night for the first time with the 8" converter and reverse valve body TH400 in the car. having never driven a car with as much stall speed before, i don't know how else to describe the experience. the converter flashes to about 4500 on the hit, which puts me at my usual shift point (5700) about 2 seconds after the launch. after both shifts the rpm's only fall back to around 5000. i have this converter in the car in advance of the solid roller setup i'm going to this winter. i'm wondering if i might have to go with less gear with the solid roller in order to put the engine back in it's powerband more of the time. the solid should make power up to ~6400~, but i'm not sure if i want to end up using only 1400 rpm's between shifts. i have a 3.55 gear in the car now with 28x11.5x15 tires. is there anybody out there who thinks i would benefit from less gear on the solid roller setup? i can't wait to see what this thing will do once i have the new valvetrain installed next spring.

 

you usually want a little more gear with a solid roller setup because the solid lifter allows the engine to rev higher with less issues

personally, i wouldn't really bother with a solid roller setup unless i'm going over 7000rpm

a good roller cam will go 6500 easy

 

i'd be happy to go with a hyd. roller setup, except for the fact that there are no new pontiac roller lifters available that i know of. i'm also trying to run in the 6's in the 1/8 on street tires, stock heads, and at full weight (~3900~ lbs). most people think i'm crazy, but i'm gonna give it a shot anyway.

 

You went to the track, but you post no sig or times? And what do you consider street tires? Cuz you sure as hell won't go 6.99 on real street tires! And why would you pick a solid roller if your only revving to 6400rpms?

 

geez...i wasn't aware i had committed a crime.

the reason i didn't post a time was because it wouldn't be relevant to the question i was asking. by street tires i mean ET streets, which happen to be the only tires i have for the car. the reason i picked a solid roller is due primarily to the lack of availability of pontiac roller lifters. the solid roller i'm running will not be radical by any means and is similar to the cam used on another car running in the 6's that's pretty near my weight. like i said, i think i can do it, but by no means will i be surprised if i don't.

the car i'm referring to is my 74 formula. the short version of the sig is as follows: 1970 462 ci block, #16 d-port heads ported by JBP, holley street dominator intake port-matched by JBP, holley 850 carb, stock crank/rods, TRW forged pistons, comp EE hyd cam (230/236, .538/.543, 110 lsa), crane gold 1.65 rr's, JBP lifters, and comp springs. the car weighs ~3900~ lbs. with me in it. it's best pass so far is 7.61 @ 90.35 on a 1.70 60 ft.

does that help?

 

Sounds like the gear is fine or maybe even not enough.
I think your stall is too high. I think 1000 rpm less would be better for your setup.

Heavy

 

Even if you only rev to 7000rpms, a solid roller is going to be benifitial in more ways than just additional power over a hyd roller.

Jason

 

do you mean for the solid roller setup?

 

What I mean is....you said you only had 1700 of rpms to play with (?). So if your cam's power range is from 3500-7000, why would you want the stall to hit at 4500 and loose that first 1000 rpms? Sure you might 60ft a little better but in the end, you loose. Just match the stall to the power range of the cam.
My cam kicks it from 3000- 6800 rpms. And my stall hits at 3000 rpms.

Heavy

 

i understand that, i just thought you were talking about my current setup. the converter was chosen specifically to take advantage of the new cam's powerband.