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Old 03-08-2018, 12:01 PM   #21
6DoF
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top gear RPMs @ 70MPH ... (42rle trans with .69 OD)

for 30s:
3.73 - 2018 <-- sux from the start
4.56 - 2467 <-- proper get up n go
4.88 - 2640 <-- b/c race car

for 33s:
3.73 - 1835 <-- fail
4.56 - 2243 <-- better than stock, but some loss to heavier tires
4.88 - 2400 <-- proper get up n go

for 35s:
3.73 - 1730 <-- total fail
4.56 - 2115 <-- heavier tires will make this feel like stock or worse
4.88 - 2263 <-- better then stock, but half negated by heavier tires

then remember me saying that motor really needs to be driven at 2500rpm or over for acquitted power and better drive-ability, the TC will help you need slightly less gear to make that happen. 4.88 on 33's would run great pending you don't like to speed a lot on the highway, it'll drive well up there but just use more gas at 80+. i've also pretty much never met anyone who had 33's on a JK and didn't go to 35's unless it was a 100% pavement pounder. this is why 4.88s.

Last edited by 6DoF; 03-08-2018 at 12:05 PM.
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Old 03-08-2018, 12:03 PM   #22
XJROB
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Hmm. it must be 3.73 then, cuz its a sport not a rubi.
(edited)
Thanks for the numbers!
ok so it looks like its between 4.56's and 4.88's, and if i graduate to 35's definitely 4.88's. I thought it would effect rpm range a little more than what you came up with. thats good to know. I do have a wife factor, she takes her on the freeway. its her daily driver, wheeling every so often. well see when it comes time.

Last edited by XJROB; 03-08-2018 at 12:11 PM.
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