Mazda RX-7 GSL-SE Rear End Swap -- Spriso Motorsports

[ACote]

Just run zero offset in the rear. Eliminates some space and a nicer looking wheel.

[Loopy]

Okay I found one of these rear ends and again it sounds like I paid too much. $500.00 with all the brake parts. Any way I need to strip it down to take it to a guy in Auburn WA to narrow it. I have never worked on a rear end. How do you get these things apart? I tried taking the cover off the third member and something will not let it go. Do you have to somehow pull the axles first?

[fj20spl311]

YES

[RCMike]

Start out at the ends.. the axles will slide out. then the center will fall out

[Loopy]

Start out at the ends.. the axles will slide out. then the center will fall out

Thanks guys. Got it.

[Vinnyz]

Reviving an old thread here........does anyone know what the maximum wheel width can be ran with a shortened axle housing?

[Alvin]

Reviving an old thread here........does anyone know what the maximum wheel width can be ran with a shortened axle housing?

Assuming you are keeping the stock fender flare...your width is limited by your leaf springs and inner fender. I'd guess 8" is max.

[Vinnyz]

Bill wrote:


If you are interested in doing this conversion to your roadster, start searching for a 1984-1985 Mazda RX-7 GSL-SE (NOT a GSL, not any other RX-7 version, it MUST be the GSL-SE!) They can be hard to find, so start searching now!

Michael

This is some great news for any of us wanting to upgrade our rearends!
In speaking with a lifetime Mazda guru friend, he stated that" All 84-85 Rx-7 rear axles that came with disc brakes are LSD 3.9 ratio and can handle 400 hp because they all came with the beefier axle shafts."
Only caveat would be the need to re-drill the lugs from 110 to the 114.3 if its not a SE optioned car donor.

[sfdaugherty]

[quote="Vinnyz
This is some great news for any of us wanting to upgrade our rearends!
In speaking with a lifetime Mazda guru friend, he stated that" All 84-85 Rx-7 rear axles that came with disc brakes are LSD 3.9 ratio and can handle 400 hp because they all came with the beefier axle shafts."
Only caveat would be the need to re-drill the lugs from 110 to the 114.3 if its not a SE optioned car donor.[/quote]

There are actually two Mazda diffs that are being used as far as I know (both are LSD):

1. The GSL-SE diff that Spriso modifies have beefier axles, ventilated discs and 4.1 ratio;
2. The GSL diff is a bit smaller with smaller axles, solid discs, and 3.9 ratio

You experts out there correct me if I'm wrong.

I'm running a GSL diff in my swap.

Shannon

[Gregs672000]

I too am running the GSL with a 3.9 and solid discs. Works great.

[Bigtaku]

Wish I could find either one of them!

[Ed Mason]

Bigtaku, where are you located?