Hi all, I'm pretty new to the forums. Just got a 84 GLS to so some racing in. I have read a bunch of the threads about the kia and miata gears but am trying to figure out exactly what I need. I have no problem tearing down and rebuilding my rear end (LSD) with kia or miata gears, but just need to find the right gears.

Does anyone have experience with 4.77 gears for racing. Are these too tall?

Also, from what I have read, i need to get gears out of a 96-newer kia sportage or 93-97 miata. I am going to go with 4.3 (miata), 4.44 or 4.77 (kia) gears. Can anyone 100% clarify what years and if the front and rear gears on the kia both work?

Thanks!!

 

Can't really answer your question, I've been wondering the same thing myself. This page might help you in your research though.
http://members.aol.com/solomiata/Drivetrain.html

 

See if this sheds some light.
Miata Diff interchange into 84-85 models (Multi-page thread 1 2)
mjm4jc
https://www.rx7club.com/1st-gen-archive-71/drivetrain-miata-diff-interchange-into-84-85-models-695127/

Are these too tall?
They are not tall. They are low gears and the lower the gear the better for 1/4 mile times. :-)

A tall gear would be a lower number like a 3.09.