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whats the best rear end ratio for my swap??

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Old 05-30-09, 06:33 PM
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tonysc400
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Default whats the best rear end ratio for my swap??

hey guys i have a 95 sc400 with a 2jzgte swap auto...i wanna change the rear end for the best ratio possible for my 2jzgte..what is the best ratio if i wanna keep it auto..right now i know i have the stock sc400 3.92 ratio..anyone has any suggestions?
some people tell me the 97 and above came 3.26 or should i go with a mk4 tt auto rear?
Old 05-31-09, 06:19 PM
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7sins
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Sc400 92-96: 3.92
97-00: 3.27
Sc300
auto all yrs: 4.27
man. all yrs: 4.08

It all depends on what you want to do with the car. If you really don't plan on doing alot of highway driving and are willing to loose some top end for torque go with the 4.27 if you want good gas mileage go 3.27
I'm not sure what a supra diff is as far as gear ratios, but that's the diff I'd use mostly cause it's an LSD
Old 05-31-09, 06:56 PM
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Wicked SC
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Since you have the Auto trans your best bet would be to go with the TT auto diff which comes with a 3.76 gear ratio.

Last edited by Wicked SC; 06-01-09 at 08:40 AM.
Old 05-31-09, 06:57 PM
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//LRD
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I really liked the 427 with my 2j off the line. But I have and prefer the 377's .I gained 12 more mph @ the same rpm
Old 05-31-09, 07:16 PM
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YeA 2jZ
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Originally Posted by //LRD
I really liked the 427 with my 2j off the line. But I have and prefer the 377's .I gained 12 more mph @ the same rpm
did you use the stock auto housing and re-geared it or did you get a new rear end ??
Old 06-01-09, 07:26 AM
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tonysc400
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377's are from the auto tt rear?..i would like to know the same as well..did you change your whole pumpkin or internals? i am planning on buying a whole pumpkin since i heard it bolt right up in the sc400 and everything should work such as axles and Driveshaft.
Old 06-01-09, 09:00 AM
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lexforlife
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the supra tt dif is a direct drop in , no changing of drive axles the only needs to change is swapping the companion flanges , take the yours off your diff and swap it onto the supra tt dif

i use the supra tt dif and i have really long gears in 3 and 4th esp coupled with my r154 tranny
Old 06-01-09, 11:20 AM
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tonysc400
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cool sounds good...i think i will hunt for a tt auto diff..i decided to keep my car auto either though i love stick but less things to break i guess plus i heard the boost holds up better...
Old 06-01-09, 11:39 PM
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do not get the 4.27 gears what so ever. it throws your speed off by a bunch. when im doing 70 it shows about 90
Old 06-02-09, 04:59 AM
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v8soarer91
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Id REALLY like to see how you would fit a supra tt diff where the soarer standard diff goes!!!!!.
There is a little bit of a size difference.

You can only fit a supra tt diff if you replace the standard diff cradle with the supra tt diff cradle.

The supra NA bolts straight in the standard soarer (sc300, sc400) cradle.
Old 06-02-09, 05:44 AM
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RyanV
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I have the stock sc300 4.08s right now, and all of the gears are too short for a turbo powerband in my opinion.

I'm about to swap in the JDM Supra TT auto diff which has the 3.76 gearing. It is a direct swap. The companion flange is the same 3 bolt flange as the sc300 diff.

With the r154 and 4.08 cruising down the highway at 70mph is 3k rpms.

If I had 4.27s@70mph I'd probably see 3500rpms which is absurd.
Old 06-02-09, 07:18 AM
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tonysc400
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you can use a USDM mk4 tt rear also can you..?
Old 06-02-09, 09:15 AM
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aliga
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i would go witht he 3.266s if you want to go 6 speed in the future.
Old 06-02-09, 09:25 AM
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RyanV
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Originally Posted by tonysc400
you can use a USDM mk4 tt rear also can you..?
Long as you use the TT automatic rear end...some apparently did not have LSD/torsen though. Not sure why, but it's what I have read so I'd do a visual inspection if I were you.

The six speed rear end requires a different carrier so that you can bolt it up.

I believe the Aristo rear end is 3.26, has available LSD/Torsen, but I think it has the different companion flange off the front for the driveshaft.

Last edited by RyanV; 06-02-09 at 09:30 AM.
Old 06-02-09, 11:33 AM
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most of you guys are posting real good info on this topic but is there a site that would show all the oem rear ends and there different ratios and flanges ??? or atleast a few sites in which i would be able to go into and get the info to possibly compile them and post up a whole list so that we can all see and compare


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