my old KA is starting to irritate me so i got to thinking about an engine swap. could i please get some opinions, info or direction to online resources of some kind relating to swapping an older 13B or 12A into an s13 chassis? i don't want to bother with turbo, i'm not doing this for any outrageous power, just a different project and i'm sure mostly anything will be stronger or at least feel better than my ka24e.

afaik the engine is fairly small so fitting it shouldn't be a problem. use the tranny that came with it, get a custom drive-shaft made to hook to the 240's diff, weld something in the way of engine mount extensions to the old ones or just straight to the frame, bolts things in, i'm sure it won't vibrate enough to bother me. hopefully use the 240 radiator and fuel pump. headers come out on the opposite side of the KA's so get an extension piece made to run across the bottom of the car. i hope i don't need to get a custom pan made...

does this sound half-way reasonable? how much can i expect to have to pay for an older NA engine? is it insane to count on getting one in decent shape? as far as i know the turbo rotaries tend to go south quick on you if you don't know what you're doing, and i'll admit i don't, but if i treat an NA with respect can i count on it lasting a while?

btw, sorry if this kind of stuff bothers anyone here. don't take my wanting to tinker with the rotaries and wanting to toss one into a nissan personally. i'm not planning on parading this thing around for attention, would jsut drive it around, have some fun with it, and hope it doesn't explode.

 

Well the stock engine in your car made 155hp, which is more than any N/A rotary except the rare '89-91 engine at 160hp but FAR less torque. The car will feel a lot slower unless you also go with deeper rear gears (something in the mid-4's range should be good for street use)

You'd be surprised how large a rotary is. I expect you'd have big fitment issues with the exhaust trying to be where the body/suspension is.

 

well mine makes 140hp, i have the SOHC KA24e. i see your point. somehow i was told that the NA rotary had 170 hp, doesn't really matter, it'd still be an interesting project either way. thanks for the heads up on the size issues, i guess i should go find one at a junk-yard and measure it out or something.

 

Well, if you port the motor and put a Weber on there and full exhaust, 200+ hp shouldn't be out of the question. Also, he could mount the motor further back in the chassis compared to the stock ka24e.

 

Probably not. One of the characteristics of the wankel is that the E-shaft is a lot higher up on the engine compared the the crank in a boinger. This means the transmission is a lot higher up. Without having exact measurements on-hand, my armchair estimate is that you'd need to mount the engine more forward or do some surgery to the trans tunnel. Note that on RX-7s the trans tunnel goes almost all the way up to the hood.

 

Yeah, go look at an old Chevy Vega and notice how big the trans tunnel is. It was meant to have a rotary, but GM pulled the plug on their Wankel engine.