4.77 gear for 1.8 miata?

[red986s]

I bought my 1.6 with a 4.10 and hated it! I was always above or below my power band in the corners and I ALWAYS got my butt kicked on the start. I switched to a 4.77 (Kia Sportage R&P), Megasquirt, and upgraded the header. It completely transformed the car!

Granted, it's a 1.6 and the MiDiv tracks I race are shorter and more technical. I shift a lot more but I've learned to adjust. My times have really improved and I'm getting podium finishes.

Don't forget there's a 4.44 R&P out there to.

[iambhooper]

Have I read everything correctly... if I have a 1.6 and want to change from the 4.3 to a 4.44, I can find a R&P from a 1st gen Rx7? I usually find myself at VIR or CMS, I think the 4.44 should help keep the rpms up in the slow corners.

Thanks in advance!

[Matt93SE]

The 1.6 diff is a smaller ring gear diameter- you'll need to use the 1.8 housing. At that point, lots of stuff will just bolt right in.
http://www.miataturbo.net/diy-turbo-...-post-4288/#13

[iambhooper]

But would that be IT legal?

[Dano77]

Nope, Not IT compliant. In IT the 1.6 car is stuck with its stock diff housing, in SM the 1.6 is allowed to upgrade to the 94-97 later 1.8 housing which uses first gen RX7 gears. The same gears are used in the RX8, the Honda S2000 and the Kia Sportage as well.

[iambhooper]

So then im stuck with either the 4.3 or 4.1?

[Marcus Miller]

There are (were) 4.8's available for the 1.6 rearend. When I ran my 1.6 in ITA, I had an Ekerich diff with them in it. I picked it up off Bowie, and I think it went with the car when I sold it.