Gears & Axles - 4.30 Gears & T56

Anyone running it?

I'm thinkin about getting a second chunk setup with Spooled 4.30's for some track fun with the T56...it might see some street action with them, not in the rain at all cause of the spool, but the occassional fun..:devil:

If/when I get a aftermarket rear I'm going to use 4.30s. They'll work good with a N/A setup with DR or 27 inch slicks with the M6. As the wise man said "don't fear the gear."

I'll be shifting at 6800-7k..was thinkin 28" tire, but the 27" looks to be more effective....might have to get a set on 15x10 rims, 27x10.50 slick.

I am..

I think the thought on 28 in slicks is a 4.56 (128mph @ 7k t56)
27 inch tire w/4.30s (131mph @7k t56)
From reading various posts it seems that between these two tire/gear options that the 4.56/28" would launch better.
Ref f-body.org gear calculator.

^He's correct merv. 28"/4.56 would be abetter combo for your T56.

I have 4.30's with 430rwhp/410rwtq. I think the 28"/4.56 combo works the best. I chose the 4.30's so that I could run a 26" or 27" tire because I didn't want the hassle of fitting the 28" tire. Works good, low 1.5 60ft times in a 3900# car. On street tires, it smokes them through 2nd gear at anything more than 2/3 throttle. So I definitely wouldn't want any more gear than that. Best of luck.

Ryan

That thought did cross my mind, I did use that website and messed with calculating it.

I'll sit on it and think about it. I currently have 3.89 gears, 28" DR's, TH350 with a 4500 stall. I want to get that out to the track first to see what it does.:)

i ran those for about 4 years at 410 hp and 2 years following at 490 with n20. loved them. ran 27" tires NA trapping 123-124 and 28" tires n20 trapping 128

That thought did cross my mind, I did use that website and messed with calculating it.

I'll sit on it and think about it. I currently have 3.89 gears, 28" DR's, TH350 with a 4500 stall. I want to get that out to the track first to see what it does.:)

Seeing what it does first is definitely the best option ... the 27" with 4.30's at 7,000 rpm will be 131-136 mph depending on tire growth (if you go with a bias ply) ... !

If you are shifting that high, I presume 7,000 is where your peak horsepower is. This is where a dyno curve is important if you have not dyno'd it yet. Why turn it that high unless you are still making power?

i am running 4.30s with a 26" drag radial on my 99, i started with 4.11s which woke the car up big time but the 4.30s really made a difference getting the car to move out of the hole.

I have 4.33's and 28" bias ply tire. Works real good, traps 123-124 n/a and 134-135 on the jug. Car would run better n/a with 4.56s, and better on the bottle with 4.10s so I split the difference. :D

Seeing what it does first is definitely the best option ... the 27" with 4.30's at 7,000 rpm will be 131-136 mph depending on tire growth (if you go with a bias ply) ... !

If you are shifting that high, I presume 7,000 is where your peak horsepower is. This is where a dyno curve is important if you have not dyno'd it yet. Why turn it that high unless you are still making power?

Peak power was at 6850..so the shift will be at 6900-7000 ish.

Peak power was at 6850..so the shift will be at 6900-7000 ish.

That sounds good, but based on this thread, http://ls1tech.com/forums/conversions-hybrids/1386312-mervs-1984-monte-carlo-ss-19.html, I would suggest working on getting it to hook before going to more gear.

Oh it hooks nasty with the Auto..cause the car is more setup for it..I've been tweaking that one here over the last week or so. Changing the setup to run for a T56 on the track will take some more work. I'm starting with the Gear/Tire combo, then working on the suspension, if I go that route.

I have the Auto setup in and ready to rock, just planning a day to go to the track and test it out with all the new stuff.

Anyone running it?

WAS... changed to TH400 and thinking about a pair of pumpkins myself (10-bolt currently) and building a M9 :D :D :D

Im running 4.30s with a 28 inch tire.. wish i went with 4.56s have ms4 cam , 6th gear sucks because the cam is choppy even at 70mph in 6th and it bucks and drives me insane. i usually run in 5th because of this......