Hmmmm. MX5 gearbox sounds very interesting. Has it been done ???

Yes, the Aisin 6-speed has been fitted to A-series. It was the S15 version which has closer ratios than the MX5 version.


More details: 6-speed

Yep I know someone who modified an S15 gearbox to go behind his A15. The gear ratios 2-5 are almost identical to the Option 2 Ultra close box

I've read up on the S15 box as well. The Miata 5 speed box = mid close and the 6 is a semi-ultra. The 5 speed Mazda box is 33-34" long so we know the issues there. The tranny is 8" in the center and 14" at the bell housing.

Modding the bell housing to fit may be just as expensive as buying a close ratio box that fits.

Tom

theres nothing in it really for UC vs AZ6 in terms of ratios. I would go AZ6 hands down and save in the long run without spending extra on close ratio gearsets.

Modding the bell housing costs but what about $80 for milling?

1. Cut the front case of transmission approximately
2. Remove front case
3. Mill the cut parallel to the face of the case
4. Repeat for A-series bell-fragment
5. Weld a circular plate to the case
6. Center the bell fragment on the plate and weld it


Use a stock Nissan clutch disc 1" x 24 spline x 180mm

And where does the gearlever end up ?
And does it fit into a manual tunnel ?

Gear lever ends up where a CA18 gearbox ends up. Same mods that needs doing for S13 gearbox.

Yes, fits the manual tunnel. Remove the existing mount bosses. Cut a slot in the center of the tunnel lengthwise, then bend open. Cover the opening with sheet metal. OR obtain a 120Y/180B tunnel which looks factory and works with the stock 1200 heater.

General Motors 2 Speed Powerglide
1st: 1.82, Drive: 1:1.
Bomb Proof!!
Well...... It's for Racing.