well where do i start i bought a 85 rx7 for $1000 dont really know much about rotary but i know and seen the power these engines are capable of and love it well long story short one day i started it and moved it into the drive way went back out to go to the store, wouldent start so i ran basic check spark, fuel, i pulled a spark plug and i was soaked with oil so im guessing i blew an oil control seal well i got a 13b (that fell off a truck)and want to put that in so i got a new rebulit tranny and im not to shure what to do next im assume i need a ecu but what kind? will the drive shaft length change? what needs to be done to the 13b to fit into the 12a frame and can any one find me a new gas tank?? please i need help bad and thats just the start of it https://www.nopistons.com/forums/pub...1047683358.gif

You need a 12a oil pan and front cover. I also had to use the oil pickup from my 12a on my 13b-RE.



As far as the ECU is concerned, I'm not sure for an NA application what would be best.



The driveshaft length shouldn't change, I know mine didn't.

thanks that shuld keep me busy let me know if you think of any thing elese i should know

Its no big deal. New motor mounts, etc. Put a SP 13b in my 81 w/ no problems. Run smooth w/ the stock 81 tranny & RB clutch & p plate. Do it.

Correction on the oil pan... You need the GSL-SE 13B oil pan. The 12A front cover will bolt on to the 13B.



Now for the tricky part. You need to slot the trans mount holes on the crossmember 1 inch towards the rear. Remember that the engine is 1 inch longer than the 12A. doing this will allow you to keep the 12A motor mounts and bracket. both 12A and 13B front motor mounts are the same. This will also help a little with weight transfer because now more of the weight is towards the rear of the car. The difference is not the mounts but the front crossmember.



I speak from experience on this. I did this same swap. I hope this saves you some headaches. Any other questions PM me.