hey guys thanks for the info I was wondering if it was worth fabricating some stuff for this rearend & if its even marketable.

thanks again tony

 

it probably would be if you could fab up a way to make the larger FD rear work.

 

There's nothing that needs to be fabricated to adapt the 7" RX-7 rear-end. It's the 8" from the FC Turbo II and FD that would require custom fabrication.

 

Just got word that the rebuild parts for my lsd are on back order til NOVEMBER!!!!! Good thing I have an insider working on parts from the states

 

I agree with bripad007,The only rearend worth fabbing up parts for is the FC turboII rearend.

If you ever decide to fab a kit for it,I will be the first one in line to buy one.

 

I didn't say the Turbo II or FD rear-ends were "worth" fabricating for, I said it would be necessary to fabricate some parts in order to use them. Personally, I don't think they are worth fabricating parts for; if you're in need of something stronger than the 7" rear-end, fabricate parts for using a 7.5" T-bird/Cougar rear-end or an 8-9" rear-end from a Ford or GM car.

 

would you rather have a solid rearend like a GM or Ford or independent rearend like a rx-7 TII & miata?

 

independent rearend like a rx-7 TII & miata.

 

I'm not talking about putting a solid rear-end in a Miata; that'd be useless.

I'm guessing you've never seen or read about the details of any of the 302/351, LS1/2/6 or 3.5L BOPR V8 conversions for the Miata, eh?

They use independent rears. Both 7.5" and 8.8", as I recall. Using those rather than the Mazda 8" rear has these benefits, in no particular order:

Cheaper.
Easier to find.
Easier to source parts for.
Many gearsets/ratios available.
Stronger (at least in the case of the 8.8").

If you're going to have to fabricate a custom mount, get a custom driveshaft and half-shafts built, you might as well go with the American rear-end(s).

 

Oh, and John Burch's "Cruise Missle" blown 347 c.i. Miata was running the 7.5" Thunderbird rear, so even the "measely" 7.5" is plenty strong for any of us.

 

What the miata community really needs is someone to build an adapter for the Turbo II transmission. With an upgraded 7" diff, it appears to me like the weak link becomes the transmission. I'd really like to see a bolt in upgrade with mounting points for the PPF.

 

dude people use the turbo 2 rears behind chevy V8 conversions, they hold up.

 

Turbo II's have viscous lsd's why would u want one???

 

The S4 Tubo II had a clutch-type diff., while the S5 has t he viscous.

As for the tranny, the 6-speed Miata/RX-8 tranny is stronger than the 5-speed, will retain the PPF and will bolt up to the engine without any extra work really.

The way I see it, if you want reliability, you follow these guidelines:

<250rwhp = 5-speed tranny w/ 7" rear
250-350rwhp = 6-speed tranny w/ 7" rear (the 7" rear has been used successfully with as much 470rwhp)
>350rwhp = T56 tranny with 7.5=8.8" rear

There's really no point in using the Turbo II tranny and rear unless you demand on keeping all the parts Mazda-sourced and you like notchy, difficult to shift trannies that're difficult to locate.

 

will if anyone needs an adapter plate for a 1.6 to TII tranny I have a template to cut one out.

 

Well, ****, that kind of changes things a bit.

Already having the tranny adapter plate in one's posession would definitely be a "pro" to going the TII route.

 

hey Brian can I get your e-mail address it seems your the man I need to talk to. I have some Ideas & pics to show you.

thanks tony

 

how sexy!