OK, so no 4.33' s How about a regular limited slip I can modify?

[Newbie]

I can probably get by with the factory limited slip. Any extras out there?

Steve:shrug:

[its66]

Steve,
As you have probably figured out, the 4.33's are pretty rare. If you are looking for a plate type limited slip to use for competition, look for one from an 86-88 GXL. IIRC, they all had ltd slip diff's. The gearing won't be optimal, but neither is the 4.33.

If you haven't already, check www.rx7club.com (http://www.rx7club.com). The classifieds there are pretty extensive.

[Chris Wire]

The closest you might come to a cheap, available unit might be a 4.10 from an automatic. The next best thing would be a 4.30 from a GTUs. More rare, and more expensive. The manual trans cars came with a 3.90 almost exclusively, I think.

[C. Ludwig]

The closest you might come to a cheap, available unit might be a 4.10 from an automatic. The next best thing would be a 4.30 from a GTUs. More rare, and more expensive. The manual trans cars came with a 3.90 almost exclusively, I think.

You got that backward Chris. The autos came with the 3.90s. The manuals the 4.10s.

[Newbie]

I've converted to EP and I'm using a dog ring box with a 1:1 final drive. My 5.12 will not cut it for the longer tracks like Road America. I ended up getting the 4.33 ring and pinion from Mazdaspeed and am calling Mazdatrix for a Kaaz 1.5. I'll use my parts car for the housing.

Take care and thanks for your help.

Steve Smyczek

[Chris Wire]

You got that backward Chris. The autos came with the 3.90s. The manuals the 4.10s.

Cool, then I've got two 4.10s sitting in my garage! I wonder if anyone has had any success running the S4-S5 as a 4-speed using a 4.10?

[mbuskuhl]

Cool, then I've got two 4.10s sitting in my garage! I wonder if anyone has had any success running the S4-S5 as a 4-speed using a 4.10?

It will work but not nearly as good as a 5.12. I had a 4.10 LSD before going to 5.12. The difference was night and day, it was the best money I've spent.

[Eagle7]

Cool, then I've got two 4.10s sitting in my garage! I wonder if anyone has had any success running the S4-S5 as a 4-speed using a 4.10?
No performance numbers, since my car went through some other significant mods at the same time as the 4.10 -> 5.12 change. However, it changes your 2-3-4 shifts into 3-4-5 shifts. You need the close ratio transmission with the 5.12. I haven't done the math to decide if 2-3-4 with the 4.10 is better/worse than 3-4-5 with the 5.12. Might be track-dependent. I do know I don't like the shift to/from 5th.

[mbuskuhl]

I do know I don't like the shift to/from 5th.

The .756 5th gear is preferred over the standard .697 or .711 - the .756 is only found in the GTUs (not to be confused with the GTU) which are very rare, in most cases you need to get the .756 from Mazdaspeed and have 5th gear replaced when doing the rebuild. Not sure what you have, but this may help the problem.

Of course there are the Miata tranny gears, but NOT LEGAL for IT.

[xr4racer]

Do you still have the 5.13?

matt

[Eagle7]

Do you still have the 5.13?

matt
Me? Yes. (in the car, not for sale)

[Chris Wire]

The .756 5th gear is preferred over the standard .697 or .711 - the .756 is only found in the GTUs (not to be confused with the GTU) which are very rare, in most cases you need to get the .756 from Mazdaspeed and have 5th gear replaced when doing the rebuild. Not sure what you have, but this may help the problem.

Of course there are the Miata tranny gears, but NOT LEGAL for IT.

I'm already equipped with a 5.12/.756 setup, I was just throwing it out there for discussion. I used to have a gear calculator that would allow the plugging in of ratios and spitting out of speed/rpm tables. Don't remember where I got it though.

[mbuskuhl]

I used to have a gear calculator that would allow the plugging in of ratios and spitting out of speed/rpm tables. Don't remember where I got it though.

Lots of really cool and FREE racing calculators here... http://www.wallaceracing.com/Calculators.htm

[racingralph]

the 5.12 is the best all-around gear for 2nd gen (its) rx-7s. you can find another gear combo for each track , that will help you be quicker . the 5.12 is the best all-around pick!

[xr4racer]

Hi Marty, I knew you wouldnot be selling yours, the question was for Steve(newbie)

matt miller