wrd1972

iTrader: (12)

Ok I currently have 400RWHP and 4.11s in my nine inch and I am ready to change gears. First off, I dont race and rarely ever go to the strip, the car is mainly a fun hotrod and thats all.

The prime complaint I have is that my 1st gear (T56) is useless if you just ease out and floor it, the tires just light up and on occasion nail the rev limiter. Also I have larger diameter 285/40/17 firehawk dual oval tires which are a very quality street tire.

So what to do, go to 3.90 or 3.73 gears? Ultimately I want a gear that allows 1st gear to hook 90% or so but I dont want to bog things down needlessly. I am concerned that going to 3.90s might not meet my needs so I am looking for others opinions.

Thoughts?

guppymech

iTrader: (7)

Other than 1st how do you like the 4.11s? If you like how they pull with your cam through the other gears, what about DRs? I keep hearing from my buddies at work how well they hook up. I don't think the 3.90s will help you out much in first. I guess if I were you I'd look at the f-body.org gear calculator with an eye twards the 3.73s.

HCI2000SS

iTrader: (2)

I make around the same hp as you , and have 4.10's as well, and love them! IMO you will still have the same problem with 3.73's on a street tire. Get your self a drag radial and you will love your 4.11's again

dr_whigham

iTrader: (49)

Dude, I've got stock 3.42's and even 2nd gear is USELESS at WOT, and that's with 315's in the rear. Maybe go 3.73 if that's really what you're looking for? I don't think there's enough of a difference between the 4.11's and 3.90's to justify the swap.

HioSSilver

iTrader: (8)

After looking at your dyno graph 3.90 will suit your needs the best with your car being a vert. You still need a bit more gear to make up for the extra weight of your car.


4.10's kinda suck for these cars.....just a bit over the top. I've had them both and had to make the change to get threw the 1/4. 4.10 to 3.90 is a very noticeable difference.

TORK?

iTrader: (27)

It sounds like gears aren't your problem. You need a better tire in the rear. Even if you put in 3.42's you would still blow the tires off those Firestones.

Get a drag radial or autox tire and be done.

FST SS

I have 3.89's and they work great in my car. I don't have as much power as you and my nittos work pretty good on the street but my M/T drag radials dead hook.

Midnight02

iTrader: (8)

I have experience with 3.42's, 3.90's and 4.10's. The primary problem here isn't the rear; it's your tires.

Tried out a few different R compound tires (used both drag radials and road race R comps) over the years and they resulted in a substantial improvement in traction on dry pavement. Of all of the mods I've done (with the exception of N2O) upgrading to a tire that will actually get traction was by far one of the best to date.

All that being said, if it isn't practical to go to an R comp tire on your car, then the 3.73's would be easier to handle than the 4.10's (however I'm still not sure it's going to be enough to do the trick).

Black 99 Bird

iTrader: (31)

I have 3.73s and 410 RWHP. I need more gear and will be swapping to 4.10s to help out with bogging down in 1st gear.