3.70 or 4.30 diff gear ratio

teebone

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Mar 28, 2008
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I currently have the tall gear and am in need of rebuilding the diff. I'm thinking I might go with the lower gear ratio when I rebuild. Currious to know what people think of the idea. I know I will sacrifice top end and fuel economy but I have never ran out of speed before I ran out of road. Thanks for any input you might have!
 

CRE

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Oct 24, 2005
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I hate the 4.3 on the highway on long trips and first gear is useless with a turbo pushing anything more than stock.... just my opinion. You could also try going with the 3.9 for something in the middle; that's what I plan on swapping in.
 

shaeff

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I loved the 4.30 in my old car. I was pushing 300+rwhp and yeah, first gear wasn't great, but any gear after it just pulled like a freight train.

I've got a T2 4:10 Torsen going in when the new car is done.
 

IJ.

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Mar 30, 2005
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shaeff;1418266 said:
I loved the 4.30 in my old car. I was pushing 300+rwhp and yeah, first gear wasn't great, but any gear after it just pulled like a freight train.

I've got a T2 4:10 Torsen going in when the new car is done.

Into a G series?
 

shaeff

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IJ.;1418267 said:
Into a G series?

That's the plan, anyway. LOL. I suppose you're going to want me to disassemble my current differential and compare the two? :)
ma71supraturbo;1418325 said:
Ian,

I've heard about this a couple of times and here's the most recent thread on it: http://www.supramania.com/forums/showthread.php?t=96336

So far I don't know anyone who has actually made sure that it

a) fits
b) is significantly stronger than the T1

So I'm very much looking forward to Shaeff's review

I'll find out if it fits within the next few months, possibly sooner. Aiming to have the differential built/usable by spring at the latest. As for strength, I guess I'll let the future 500+ rwhp (gt35r variant) do the talking. I'm not easy on my cars, but I maintain them like clockwork. Should be interesting!
 

IJ.

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ma71supraturbo;1418325 said:
Ian,

I've heard about this a couple of times and here's the most recent thread on it: http://www.supramania.com/forums/showthread.php?t=96336

So far I don't know anyone who has actually made sure that it

a) fits
b) is significantly stronger than the T1

So I'm very much looking forward to Shaeff's review

shaeff;1418335 said:
That's the plan, anyway. LOL. I suppose you're going to want me to disassemble my current differential and compare the two? :)


I'll find out if it fits within the next few months, possibly sooner. Aiming to have the differential built/usable by spring at the latest. As for strength, I guess I'll let the future 500+ rwhp (gt35r variant) do the talking. I'm not easy on my cars, but I maintain them like clockwork. Should be interesting!

I thought the case offsets were all wrong and they don't bolt in?

Apart from the high speed oiling issue I never broke my T1 :)
 

foreverpsycotic

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I have 4.30s in my supra, seems perfectly fine with BPU mods (albeit on a 1jz). The only downside for me was that 4th topped out at 125ish (gps).