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Diff Ratios

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Has anyone determined what the stock diff ratio is?

Lenny have you determined what the diff ratio of the lower gears you are experimenting with is?

rocmoc n AZ

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Has anyone determined what the stock diff ratio is?

Lenny have you determined what the diff ratio of the lower gears you are experimenting with is?

rocmoc n AZ

The stock Trooper diff gearing uses a 15 tooth pinion with a 32 tooth ring. The Renegade gearing that Jarrad sent me uses a 14 tooth pinion and a 32 tooth ring.

From everything I could tell with close inspection and some measurments, I found the ring gears of both gear ratios to be the same. That would mean that all you would have to do is change the pinion gears, one front and one rear. This wouldn't be real expensive. You will have to reshim the diff to get everything right. Rocmoc, you have my diff upgrade kits so you should have enough extra shims to do the job. If you were to look in a gear cataqlog for gear cutters for machining gear teeth, you would see that each cutter is good for a range of teeth. In other words one cutter may cut teeth for gears with 19, 20 and 21 teeth, if you go to 22 teeth you have to go to the next cutter. That tells me that the 2 different pinions could very well run on the same ring gear. Maybe Jarrad could compair the ring gears to confirm my findings. He is pretty sharp on this stuff. I suspose that I could have gotten 2 Trooper ring gears instead of the Renegades in error but I don't think so. My new gearing is nice. It gives me that little bit of lower gearing to make my 31 inch tires act like 29" tires. That is half way back to the stock size. I can climb any grade that is climbable without getting a running start at 1200 rpms. My super charger has a lot to do with this too. I'm currently in the process of putting a Megasquirt ECU on my Trooper which should improve this. I was hoping to get it done to meet you guys in Yuma but it doesn't look like I'll make it.

Lenny

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Man that is a high ratio. Tranny must really be low ratio design. But it does make it easier to find a replacement manufacture for diffs. I have gear ratios for my race car from 2.50 (for road racing) to 3.62 (for short track) and they are all Toyota. I was looking at BMW diffs yesterday and ratios would work. It is a simple independent pumpkin in housing with similar mounts. Driveline & axles could be built at a driveline shop. Will look at Subaru next. Just looking ahead. My greatest concern is cost of new factory parts. You can purchase a good complete BMW diff for less than $250. How much is the gear set, Lenny or Snowman?

rocmoc n AZ

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