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5th gear change out

Old 06-29-06, 03:18 PM
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5th gear change out

Im getting my tranny rebuilt next week at ISC and was thinking about dropping in the better 5th gear ( I currently have the stock 91 ratio now).......I was wondering if the people who had it thought it was worth the $?

I will be running Moroso, Daytona, Sebring, and Homestead.

Thanks in advance
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Old 06-29-06, 03:24 PM
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I would say it is well worth it. Especially since they are already rebuilding the tranny. A couple of hundred bucks makes for a real 5th gears vs. the overdrive like stock fifth. I can't speak for the tracks you mentioned, but it works well for MidOhio, VIR, IRP, Gingerman etc.
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Old 06-29-06, 03:58 PM
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5th will still be an overdrive, it will be from a truck though which is .85:1 instead of about .7:1. It works great at every place but Daytona. We switch back and forth on the EP cars. It really is nice on the Sebring short course with a 5.12 rear end.
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Old 06-29-06, 05:28 PM
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Well, the only legal ratio is the .756 from the GTUs. With that gear, 225/45 tires, and the 5.12 you're good to about 130mph at 8000rpm in 5th. I've heard that won't cut it at Daytona. But I've never been there. Ask around. Mike will know. Otherwise the shorter gear is the only way to fly.
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Old 07-03-06, 04:22 PM
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The .756 with the 5.12 will work at Daytona. Good on both config's of Sebring also. If you have a 4.88, the 5th gear is even more critical to have the .756
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