4.3 or 4.7 diff ratios

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mrpham
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4.3 or 4.7 diff ratios

Postby mrpham » Thu Jan 12, 2012 10:21 pm

Hey all.

I found someone that has a collection of Kaaz 1.5way LSDs for sale, and he has them in 4.3 and 4.7 ratios.

Not sure what to get and I'll be sticking with my 5-speed. Would love the added feel of acceleration but not sure about driveability.

And in real word situations, will the 4.7 ratio diff provide better acceleration only in gear? Because from a stand still acceleration you'll be shifting earlier/more often?


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Re: 4.3 or 4.7 diff ratios

Postby NitroDann » Thu Jan 12, 2012 10:39 pm

Depends what cams you are getting.

4.3 is the stock ratio.

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Re: 4.3 or 4.7 diff ratios

Postby sailaholic » Thu Jan 12, 2012 10:49 pm

Plohl drove a 4.7 the other day send him a pm. Said it was quick though.

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Re: 4.3 or 4.7 diff ratios

Postby NitroDann » Thu Jan 12, 2012 10:53 pm

Probably very similar to a 4.3/6 speed combo which I had and broke the diff. and then broke another diff, and another, and after jus one more I went to a 4.1 torsen.

Was snappy as hell with the 4.3 6 speed combo. Not sure if it was actually faster in total though, I doubt my cams are big enough to give a narrow enough powerband that the taller gearing is hurting me.

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Re: 4.3 or 4.7 diff ratios

Postby toppertee » Sat Jan 14, 2012 3:52 pm

sailaholic wrote:Plohl drove a 4.7 the other day send him a pm. Said it was quick though.

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Hi Sailaholic,
That was my mx5 he drove.
It a T1 torsen, with a KIA 7'" ring and pinion 4.78 ratio. No problem so far. It's not a DD, I just use it for track days and hill climbs.
It got about a 14% differences in ratio first and second are still very usable, but it really helps in the taller gears.
At 100km your rpms 14% are higher. So that would be the only down side for highway running
BTW i'm 6'2 100kg and with two of us in the car, he still thought it was quick. Best mod I've done by a mile.

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Re: 4.3 or 4.7 diff ratios

Postby Jace » Sat Jan 14, 2012 4:52 pm

I drove nanotech's car on 14" 155/55's and it was rally-car-like chewing through the gears. Felt great.


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