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Discussion Starter #1
Well, I finally found someone to do the IRS swap with, but the car has 4.30's in it, and to avoid the hassle of having to swap two sets of gears out, I think I'm just going to buy the guy a set of gears, and leave the ones in the IRS be.

I have a beater that sees most of my highway duty...fuel milage is no real concern. Obviously with the IRS, I don't plan on going to the strip much anymore, but I was thinking about doing some open track and autocrossing. I know a few of you guys have gone to 4.30's in your GT's...what are your thoughts? Opinions?

Bart
 

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I would be willing to bet that 4.30s would help you around an Auto-x course, since I would think you could stay mostly in second gear.

As for open-tracking, I would think you'd wind up in fifth gear alot more than you wanted. I guess that's not necissarily bad if fifth gear pulls hard...

So, TTT with my question added. :)

How does fifth pull with 4.30s?!
 

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Discussion Starter #3
Geez...I figured someone would have somethin to say about this...anyway, ttt.
 

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well, I don't have too much experience but I did drive my friends GT with 4.30's, it wasn't bad at all. He runs 150 shot of nitrous with the 4:30's too, granted he does spin the hell out of the motor (raised the rev limiter). Like I said, I've only driven it once but it didn't seem too bad - I guess just try them out, worst case cenario you have to swap them later. I'd hook you up with him for a ride but the car won't have a motor in it again until next spring:(
 

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I don't really see a big benefit from the 4.30's as opposed to the 4.10's, at the drag strip anyway. The main thing I can see, is that you'd be crossing the traps a little closer to redline, as opposed to the 4.10's. As far as road racing and auto X, I don't have any experience with it, so I'll let the others chime in.......
 

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Driveability wise they are fine. I drive to and from work every day 75 miles with my 4.30s and they haven't given me any problems. Traction can be a problem if you're heavy on the pedal at every light but if you drive reasonably they are easy to control. I can't comment on auto X I'm alergic to that stuff! :D

Bill
 

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Discussion Starter #7
Well, since I don't drive like Blackout, and the other mouthbreathers around here, I don't think I'll have problems with traction. If anything, I'll just have to remember to walk the car out of the hole when I do decide to get on it. Thanks for the input.

Bart
 

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I remember reading somewhere a while back that if you are autocrossing or some road racing, that you don't want to go over 3.73's. This give you a 4 gear top speed of like 130? 4.30's will make you shift to 5th and it is like hitting a brick wall.

The other reason for 3.73's as a max is that you will have way too much power on oversteer. You will spin the car alot easier even if you are watchful on throttle. I too want to autocross and I have been told to get 3.73's. GT's have enough torque with the higher gears, that traction below 45mph with 4.30's on those types of tracks is very limited at best. My car now bogs just slightly with the stock 3.27's so I think the 3.73's will be perfect for slow corners in 2nd gear and mid speed corners in 3rd.

Just my $0.02 and some input from experienced road racers. The key is not having more power, but actually getting it to the ground.
 

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I agree with aggie97, 4.30 gears is too much for a GT. For Auto-X I think 3.73 gears for a GT and 4.10 gears for a Cobra. You do not want to have to go to 5th gear. With 3.73 gears you can stay in 3rd gear most of the time, since the car will have good power from 35 to 90.
 
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