I have a series 1 carb 13b engine that I’m possibly swapping into a Isuzu pup. It’s a 5 speed msg-5et. It’s 3.41/1.97/1.36/1.00/.86 ratios. The rear diff is 4:10 but that can be changed.
Would the engine operate with this setup? It’s a 1.9l gas engine now.
it would be alot easier to have Kennedy make an adapter then swap trans.
thanks

 

Those gear ratios are very close to those used in the 77-78 RX4 and the 2nd Gen RX7s. My 2 cents is that they would be fine with the 4.10 diff.

 

Those gear ratios are similar to a Miata so would be pretty good. Tire diameter has allot to do with the ideal rear end ratio but as long as you have options then that won't be an issue.

I adapted a Jerico (NASCAR transmission) to a 13B. The keys to making it happen was a bell housing that fits a rotary engine and an input shaft that fits the Mazda pilot bearing. For the Jerico that means using a modified Chrysler Hemi/440 input shaft, an RX4/Truck bell housing and a 2" thick adapter between the bell housing and the transmission. The Jerico case also had to be modified because of the starter location in the 13B.

If you do a Mazda transmission you would need to make a rear trans mount (or modify the existing mount), figure out the shifter handle location in the cab, and get a custom drive shaft made. That sounds easier to me than building an adapter for the Isuzu trans.

 

Any recommendations for places that could make the adapter?