Looking for gear ratio advice for autocross
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Looking for gear ratio advice for autocross
I autocross a 99 coupe in SSM and I want to do something to help me out gear ratio wise. I've been planning on going to a C5 Z06 tranny but now I'm wondering if swapping to a 4.10 rear gear may be a better option. I run 315/35/18 A6s in the rear. It's not a race car and I drive it to and from events but it only sees around 5K a year. Any advice is appreciated!
#2
Burning Brakes
When I was doing autox i went to a 3:90 and running the numbers gives you slightly lower gearing in 2nd than the ZO6 box. It worked good, get into 2nd and leave it there..
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Burning Brakes
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I have 3.42 gear ratio with the MMN6 trans which is the one you currently have and i have been very happy with it i put the car in second and leave it the my car had about 425 hp to the rear wheels. where is yours currently setting for power? that will also have an effect of what you should choose for a gear ratio. to tall and you will be spinning alot and not enough and you will be bogging which i assume you are doing now?
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I was around 420 at the wheels but I'm in the middle of a head swap which I'm hoping will put me somewhere around 440. Right now the car will do around 80 or so in 2nd and I'd like to get that down to somewhere around 70-72. I want it to get out of the slow tight stuff better, I feel like any HP advantage I may have is being lost with the tall gear. I've only been at it for a couple of years so I know my driving has more to do with me getting faster than anything else but I'm trying to make gradual steps with the car, every little bit helps. Thanks for the help guys, I'm gonna look into that 3.90 idea further
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Burning Brakes
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Are you seeing Equal tourque numbers with that also? i was around 430 for TQ so i didn't seem to have much issues and i ran in lincoln this summer till i had engine faluire at a track day. But i know during the Pro solo i asked around and i was the guy with the least amount of power in SSM
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My torque was about 400. I do mostly local stuff so I'm typically racing a bunch of Miatas. I know I'm not going to be competitive on a national level but like I said, my car is the least of my problems. I happen to live really close to Erik Strelnieks and he co-drove with me at a local event recently and beat me by a little more than a second on a 45 second course but I did learn some things. He did think a little more gear would help my car. I also took a ride with Beth in their RX-7, that thing is just brutally fast.
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Burning Brakes
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Ahh yes i had a nice Chat with Erik at the pro Solo in Lincoln that car is definatly something else Gave me some good advice. I also picked up a co driver for my car to help me out for a few events and that was also one of the best things i coulda ever done.
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You'll probably want the top of second gear to be around 68 to 72 mph.
If it were me I'd go with the MN12 tranny, 3.90 rear and raise the rev limiter to get me to 69 mph with the A6 17/35/335s on the rears if I could.
If it were me I'd go with the MN12 tranny, 3.90 rear and raise the rev limiter to get me to 69 mph with the A6 17/35/335s on the rears if I could.
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Thanks for the ideas. I'm really beginning to lean toward the 3.90 option. I've still got a few weeks to get everything done that I want to get done but this helps. I got the heads bolted on today so I probably should make sure that my car will still run after I finish "mechanic-ing" on it before I get to caught up with tearing the back of the car apart. Thanks again