Hello im very new here and I am looking for some insight.
First of all my name is Josh, I have a 1990 mx5 that im in the process of doing a 13b swap. Motor mounts and trans mounts are done but now i am upgrading the rear diff. By doing so I am using the fd diff and was thinking about doing a sub frame swap i am more than capable of the fab work i know its not bolt in just trying to figure out the wheel base difference before i order a $1000 complete subframe so i need some rough measurements and yes i know its a diffrent bolt pattern i can fix that later with fd hubs up front. sorry for the grammar i am not the best at it.

 

welcome to the board, Josh.

i'm assuming that by "rear wheelbase" you actually mean the "track"?

all that information is here: https://www.rx7club.com/3rd-generati...r-need-694523/

if you are inclined to share, please be sure to post a build thread. i, for one, would love to see your project.

 

FWIW...kind of confirming the rear track of 57.5", I laid a tape measure on the garage floor and eye-ball measured between the rotor hats and got ~60".

 

i will be posting my build at a later date its all madd scientists right now but if yours was 60" il have to measure mine in the morning might be doing a fd rear subframe and suspension swap to get that 4-link😎
il be running the fd diff anyways with 3.90s 4spd auto big stall converter havent decided on which one yet and of course a big ole whistle with time