GottaFixxxIt

Hey, I have been reading a bunch of posts, and read alot in the various FAQ's and it seems to me that the parts for my engine are getting more than abit rare.
Is it possible to croos gen engine swap, or do you need the whole drivetrain?
Would a 20b or Renisis fit in a 1st gen? *shrug* figured Id just throw that out there.

Aaron Cake

iTrader: (1)

Any engine will fit in any car if you have a welder and fabrication skills. Or enough money to pay someone with a welder and fabrication skills.

Any rotary engine (ie. S4 T2) will bolt to any rotary transmission (ie. RX-2) if you match the flywheel and clutch assembly to the transmission. There are some exceptions and sometimes the front counterweight needs to be swapped.

Is there are specific swap you are considering? It's far easier to give advice when you are not asking an arbitrary question.

Generally the NA RX-7 transmission (whether 1st or 2nd gen) is considered weak so normally a TII transmission is used when swapping turbo engines.

GottaFixxxIt

Sorry about the broadness of my question...I'm Very new to the rotary engine. so what you're saying is (aside from chopping up my engine compartment and dropping in a tuned 350 smallblock)that i can effectively drop any rotary engine in my Poor ol' RX-7 and it will work fine? (aside from engine mounts....that's almost a given...)
You have just made my day!
No i did not have anything in particular in mind as of yet....still researching. But my hope has been restored!

Btw...Awesome avatar! FightClub an exellent movie!

Aaron Cake

iTrader: (1)

Not quite. Different engines will mount in difference places. For example, the 1st gen engines mount on the front cover, the 3rd gen engines mount on the rear iron, and the 2nd gens mount on the middle iron. Nice, eh? But good news is that all RX-7s have subframes so it's usually easy to weld up a set of mounts. Or, if you are putting a later engine into a 1st gen, just swap a 1st gen front cover on and use the GSL-SE crossmember (or make one).

But yes, generally engine swaps are pretty easy physically. Then wire them up with the standalone of your choice and Bob's your uncle.

GottaFixxxIt

I still have a bit more reading to do, but i am beginning lean tward the renisis. Just seems that if your going to up grade then ya may as well go as far as your budget allows.

I woul be stuffing it into a bone stock (for the moment) 1985 rx-7 gls.
I am pretty convinced that i need to rebuild the engine considering the previous owner was lead footed and maintenance ingnorant. (date on oil filter was 1998!!!)

As much as i love driving it i have had to park it due to the constant volume of smoke, and difficulty downshifting from 3rd to 2nd. not to mention a myriad of other things. (went to check the grease in my front wheel bearings and found both rotors cracked) and the list goes on.

But...if I can put a more powerful engine in it while im hunting down parts for the original 12a then at least ive gotten a good start.

heh, Bob. lol

Aaron Cake

iTrader: (1)

The Renesis is a bit different. Because it's an OBDII engine you will need the entire harness from the RX-8. I also think that the ECU tends to freak out unless it sees the wheel speed sensors so you'll need to add those as well.

If you go standalone, be aware that the Renesis has three stages of injector and two stages of port valves. It's going to take some effort to make all of that work.

GottaFixxxIt

GAK! those are things i did not know! Thank you! (info like that is why i like this forum) hmmmm....is the 20b more "plug and play" or will i have similar issues?
I know that changing to a different engine type always has its issues, lust looking for the best compromise between exellence and pain in the assness.

Sorry about all the questions but my 12a is the only rotary i have had any experience with and that has been fairly limited to basic tune up stuff, and chasing various leaks.

Another pain is just reading about things....So much better with hands on....

Hazard15301

iTrader: (5)

If you want an easy swap, just swap the 12A for a 13b N/A, or a turbo if you so desire. You will definitely notice the power difference, and it is much simpler than the renesis swap.

Aaron Cake

iTrader: (1)

Nothing plug and play about the 20B. The only real "plug and play" are engine swaps from your series of car. That is, a FB into FB, S4 into S4, s5 into S5, etc. But generally only minor work is needed to make a different engine fit.

For example, to fit a 20B you need to make a set of custom mounts and deal with the flywheel issue (aftermarket flywheel because all 20Bs are automatic from the factory). Then the real work is the EFI system.