Building an RX7 LSD diff

Technical info not specifically 1st gen RX7 related.
TOOL
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Re: Building an RX7 LSD diff

Post by TOOL » Mon Nov 07, 2016 12:42 am

Yes LSD. Busted to hell. Probably B series truck / Ford. No way T2.
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Rubarotary
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Re: Building an RX7 LSD diff

Post by Rubarotary » Mon Nov 07, 2016 11:38 am

Indeed one is Just scrap metal but the second one is ok but if i could find axles to match And Same witdh of An rx7 would this be An upgrade ? I now Have a standard lsd.

Thanks For the help, great info on the thread btw.

TOOL
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Re: Building an RX7 LSD diff

Post by TOOL » Mon Nov 07, 2016 12:33 pm

8 inch will not fit FB.

Why do you want to change your LSD?
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Rubarotary
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Re: Building an RX7 LSD diff

Post by Rubarotary » Mon Nov 07, 2016 4:02 pm

I'm thinking about putting a 13b Turbo in but since i've been told the original lsd would only hold about 250hp i'm afraid i'm gonna Break it.
If i could find a possibility to upgrade the front brakes without having to fabricage something i would stick to the 12a.
I've been looking to put some fc brakes on but since it al has to look somewhat original For ( what you call mot ) .
But Back on topic that's the reason why.

TOOL
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Re: Building an RX7 LSD diff

Post by TOOL » Tue Nov 08, 2016 1:55 pm

T2 engine is only 200hp. The S3 has thicker axles which is a weak point in the earlier cars. The diff is probably next in line, but they're good units. It's torque and driving style that kills them.

Go easy on it and it will last.

To upgrade you'll need to change the whole rear end.
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Rubarotary
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Re: Building an RX7 LSD diff

Post by Rubarotary » Tue Nov 15, 2016 10:24 pm

Ok i'll give it a go with the one i Have, but if i do need something stronger i'm guessing i'll Have to go with a Ford axle or something?

Thanks For All the advice so far

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spirit r
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Re: Building an RX7 LSD diff

Post by spirit r » Tue Dec 27, 2016 4:56 pm

TOOL wrote:
TOOL wrote:If anyone else is interested in a lower ratio ring and pinion for their diff, let me know and I will keep searching. It's been a lot of research and some trial and error, but I'm starting to get results.

Let me know what ratios you want.
Sunday night bump on this.
LSD 26 spline 4,1:1 ratio all new bearing and sealing included and post to germany Andy?

TOOL
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Re: Building an RX7 LSD diff

Post by TOOL » Tue Dec 27, 2016 5:32 pm

Not any time soon.

The bearings aren't cheap either.

4.1 comes from an MX5. Easy to get.
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spirit r
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Re: Building an RX7 LSD diff

Post by spirit r » Tue Mar 21, 2017 6:07 am

Honda 2000 diff will be a Option too.

http://www.solomiata.com/Drivetrain.html

TOOL
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Re: Building an RX7 LSD diff

Post by TOOL » Tue Mar 21, 2017 9:01 pm

Only for the CWP really.
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