SC300 W58 manual 4.08 to 4.27 gearset swap
#16
Lexus Test Driver
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The early supra r154s got the 3.909 ratio and later switched to 3.727.
The sc400 is 3.916 and supra twin turbo auto is 3.769.
The soarer got the 4.08 but it was a 1jz, less displacement and torque and higher revving than 2jz.
the mark 3 supra rear end if interchangeable only with the is300. the 2gs, 1sc and mark 4 supra differentials are interchangeable.
r154 and w58 gear is almost the same. So you want either the supra tt auto for longer gearing or sc400 for shorter gearing. Both are close to the way toyota wanted it from the factory with a 3l engine.
The sc400 is 3.916 and supra twin turbo auto is 3.769.
The soarer got the 4.08 but it was a 1jz, less displacement and torque and higher revving than 2jz.
the mark 3 supra rear end if interchangeable only with the is300. the 2gs, 1sc and mark 4 supra differentials are interchangeable.
r154 and w58 gear is almost the same. So you want either the supra tt auto for longer gearing or sc400 for shorter gearing. Both are close to the way toyota wanted it from the factory with a 3l engine.
#18
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wow... thanks for the corrections smh!!
but i like to break everything down sorry just a bad/good habit
1. even if i got the mk3 diff and gave it to a shop to make work in either the 4.08 or 4.27 at the end of the day i would be wasting my own time becasue it's impossible.. even if they tried to mod it.. right?
2. only options i can actually choose from that gets me a lsd and lower gears is either the 3.72 from the later mk3 or 3.76 from the auto tt mk4 right?
3. and am i correct with the whole comment about the 4.08 not being that big of a difference from the 4.27 or will the 4.08 give me everything i want short of the lsd issue?
but i like to break everything down sorry just a bad/good habit
1. even if i got the mk3 diff and gave it to a shop to make work in either the 4.08 or 4.27 at the end of the day i would be wasting my own time becasue it's impossible.. even if they tried to mod it.. right?
2. only options i can actually choose from that gets me a lsd and lower gears is either the 3.72 from the later mk3 or 3.76 from the auto tt mk4 right?
3. and am i correct with the whole comment about the 4.08 not being that big of a difference from the 4.27 or will the 4.08 give me everything i want short of the lsd issue?
#22
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cant really make out the chart that wheel but all i know is it comes with a $1100 price tag
am i correct: open means its the 2 way lsd option?
and the torsen means it's the 1.5 lsd option?
#25
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W58 are the weakes option to go with for sure. However, in the OP's case, this is just another excuse he's throwing outhere. I have a 1J with some BPU upgrades and a W58. Have not had any issues, since I'm not pushing huge numbers. A simple NA-t set up will not put you past or even close to the threshold of the W58. You'll need some engine upgrades before the W58 starts being an issue on NA-t set ups.
Last edited by GS FONZy; 05-20-11 at 07:50 AM.
#26
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W58 are the weakes option to go with for sure. However, in the OP's case, this is just another excuse he's throwing outhere. I have a 1J with some BPU upgrades and a W58. Have not had any issues, since I'm not pushing huge numbers. A simple NA-t set up will not put you past or even close to the threshold of the W58. You'll need some engine upgrades before the W58 starts being an issue on NA-t set ups.
As for the W58 being durable enough for moderate boost setups? I'm sure it is but personally I will go with an R154 swap at that point.
#27
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I have yet to see a B.A.R. approved 2j swapped. Not saying that you can't do it, but lets just say I'm pretty sure it won't happen. Either way if your plan is to go 2jzgte, why waste your time with useless gears that are counter productive of your ultimate goal. You're right, to each his own, but I just think you're working backwerd or posting just for the hell of it.
#28
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Because of that I am willing to try some slightly more aggressive gears in the short term. With them the car won't out accelerate an M3 or a 2011 V6 Mustang (ridiculous comparative examples have been used intentionally) and I'm not expecting that, nor do I care to race other cars on the street. I got over that years ago. I can change back to the 4.08 differential any time without much trouble.
Swapping out a whole engine and all it's wiring because of some smog related issue... that is a lot of trouble. The expense (other than the annoying cost of going fully USDM) of a swap isn't my issue. It's the legal unpredictability of what can happen with that swap when living in California that is my issue. Were it not for that I am certain that for the money a 1JZ would easily satisfy my modest power goals.
The gear change was originally intended to be done with a TT Auto diff install but based on the responses in this thread I will just try the 4.27 pumpkin first. If I don't like it and give up on my dogged desire to have firsthand experience, out it goes and in goes the 4.08.
Last edited by KahnBB6; 05-01-16 at 01:04 AM. Reason: Grammatical fixes
#30
Lexus Test Driver
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Get that SC400 diff. It's a direct swap.