Import-Slaya

I'm about to preorder my gearset from the local shop doing the install. I've been going back and forth on 4.10's or 4.30's for this car. And am back in the middle and undecided (but starting to lean back to 4.30's). :bang: Talk to me people.

Where I live (Maryland), the bulk of the street fun is stoplight races and also blasts up to about 100 on some roads (maybe 120 on the highways). The roads just aren't conducive to the full-on-hit-the-speed-limiter type of runs some others get to do. Lots of twisty-turny back roads where you get stretches to jump from 40-80 and back down. I'm leaning towards 4.30's again, since I'm looking for the neck snapping type of jump when I stab it, or just quicker acceleration through the gears when easing into it.

My commute is less than 10 miles each way on back roads. I may hit the strip occasionally, and I will also hit the open road course occasionally (Summit Point) where top speed on the straight will peak at about 130 or so. On the road course with 4.10's I'll be making the shift to 5th for that, so I'm thinking 4.30's will at least allow 5th to pull better if I'm going to making that shift anyway.

I've made spreadsheets of all the speeds/rpms/tranny gear to compare 3.55 to 4.10 to 4.30 and even 4.56 (now I know why for pure 1/4 mile the 4.56 is nice for a N/A car!) and the difference between 4.10 and 4.30 doesn't seem like it would bug me (e.g. cruising at 80 is a bit under 3000rpms.

What has started to sway me to 4.30s again is trolling the Mach 1 forums. Many have 4.10's and wish for a little more gear, and many more have 4.30's and love them. On our cars, the 4.30's are really equivalent to 4.20's in a Mach 1, which would seem perfect (especially given that with a reflash, our cars are very happy reving up to 6500 and still making good power). That, and our overdrive is 0.68 vs. the 0.62 for the Mach 1's, so 5th becomes a decent acceleration gear for us. (I'm not concerned with fuel economy, since I don't really put many miles on it).

Sorry for the long-winded post... :drive:

Clem

I'm in Maryland also and I have the 4.10's. I never gave consideration to the 4.30's even though my car is not a daily driver. Even with my minimal mods (listed below) traction is dicey through 1st and on WOT 1-2 shifts it can get ugly, especially on some of the recent cold nights. Sure is fun but not condusive to trying to get a jump on those AWD guys, you know, like a modded WRX. I can't imagine what kind of tire roasting would occur with the 4.30's. My Fuzion 255's aren't the grippiest, but they do stick better than the stock Pirelli's. The 4.30's might be more fun if you have sticky rubber to hook up on, say like drag radials.

Another thing you might want to consider is gear noise. The steeper you go the higher the chance. These '05 rears are very sensitive. I went through a set of Precision 4.10 that howled before getting it right with the FRPP's and this was with a top notch installer. The 4.10's also accentuated my slightly wacked out drive shaft (.010 out) and now I am sporting a decent vibration from 50-60 mph.

But hey, don't let me talk you out of 'em. I all in favor of going quicker as opposed to faster. And around here, there just ain't enough room to go fast!

MikeOxbig

I've got 4.30's and they feel like 3.55's in a fox body mustang.
I've got a 5spd, and had 3.55's which felt awful. I switched to the 4.30's about a year ago and wasn't really impressed. My 92 w/ 3.73's feels alot better. I thought the 4.30's were going to make it feel rediculously fast, but I was wrong, just shift faster now. Oh, and mine doesn't really spin that bad.

Cleveland

on stock tires the difference between 3.30s and 4.10s were night and day. With an extreme lack of traction I picked up 2/10ths in the 1320. I couldnt imagine 4.30s (automatic) with all my highway driving....ouch

my suggestions for street/strip use:
automatic, no more than 4.10s
manual, no more than 4.30s

-Dan

don_w

In general, I tend to agree Dan. But, I do allow myself to "imagine" 4.30s with my automatic from time to time. The difference at 75mph between 4.30s and 4.10s is about 130rpm. Maybe not as bad as you think...

Cleveland

410s for an automatic and nitrous is....i'll find out if I can keep it out of 5th by having my shift points raised to 6400 from the 6200 I already have programmed in.

-Dan

eighty6gt

Get the 4.30's.

Import-Slaya

By the way, I have a 5 speed MANUAL in case there was any confusion.

I have until Friday to decide. Still leaning towards the 4.30's, but did find some posts about having to grind the cross-shaft to get them in to the stock carrier. Not sure if I like that idea...

Keep the input comin'!

Import-Slaya

Heh heh heh. There sure are a lot of those pesky suckers around our area. Trust me, after driving one for 2 years, I will NEVER underestimate an import that pulls up next to me and revs on me. The GT stock is faster than my modded WRX, but a good all-wheel drive launch can't be beat (not with stock tires at least).

clockworks

I was very hesitant to get my 4.10's. I wanted 3.90's, but was scared of gear whine, so I decided to just go for it with the 4.10's. To my surprise, nay shock, they weren't as drastic as a difference than I thought they were going to be. From some of the threads I've read on here, I though 4.10's were going to be on the verge of unstreetable...not so by a long shot. In fact, when I was driving them home from the shop, I pulled over and checked my old gears to make sure they actually installed the new ones.

My case was one of extreme over expectation. I do notice/realize now that the 4.10's pull MUCH harder than the stock 3.55's, but no where near the realm of "unstreetable" or "too much for a daily driver." I love mine and think they are perfect for me.

The only time I've had major traction problems was at the track...i.e. from a stand still. 1st to 2nd definitely squeals, but not to the point that I think it's hurting my time too much. I'm on the stock Pirelli's.

nonsensez9

take your cruising speed rpm, divide by 3.55, multiply by 4.1, or whatever new gear is, and that is roughly your new cruising rpm.

70 mph is about 2200rpm with 3.55
2500rpm with 4.10
2650rpm with 4.30

not that bad really, even with 4.3's

Import-Slaya

I actually have spreadsheets of speed at rpms from 2000-7000 in 500 rpm increments. With the amount of highway traffic around here (and police running radar/laser), cruising at 80 is about as high as you can go, which is still under 3k.