12a vs 13b in a VW Beetle?
 

Hello all,

I know I'm probably going to get some sh!t for trying to put a rotary in a VW Bug, but that ok. My only experience with rotary engines is the one in the UAV I used to fly for the Army (the Shadow 200, if you care).

I'm looking to replace the stock VW engine with either a 12a or 13b. I'm having a hard time finding solid information on which one would be best for this application. I'm looking to build a daily driver that can put out around 150 to 180 hp. I'd like to get at least 20 mpg, but I don't know if that's realistic or not. I'm also looking to have the engine power the Mazda's AC unit that I'll transplant into the Bug. The heat in Texas can be intense.

Any advice would be appreciated.

I'm sure it's been done, as far as what motor to use, I'd just get whatever you can find, they'll both have enough power, they're not that different proportionally, and either will make a sufficiently big project. I'd look for dune buggies with rotaries for ideas. I'll get back to you if I find anything.

Way wrong.
 

Well, guessing never beat research, did it?

I've got you the hook up right here.

https://www.rx7club.com/old-school-other-rotary-63/rotary-beetle-update-691425/

Shows pictures, lots of technical stuff, and sources. Apparently, the 12A does fit alot easier than the 13B, from what little I've read.

Try looking though the forum's titles closer, it makes this site alot more useful. I found that link in "other rotary"

I'd go with a 12A if I were you.

I did the 12A for starters, just stock with an exhaust I made. Fitment wise there really isn't much difference, both will fit under the decklid. Hell I've managed to cram a Porsche 5 speed transaxle and a 13B (raised 2" for ground clearance) and the decklid still closes.
The 13B doesn't have the cross member mounting holes on the front cover like the 12A due to the FC getting a the engine mount on the bottom of the engine. You really don't want a 13B free hangin off a VW transaxle without an extra brace back there. You may be able to run the 12A front cover or one of an early FB 13B front cover (Don't really know what ones have the mounting holes) I'm making a lil sub frame and will be picking up off the stock bottom of the engine mounting point to keep the whole drive train well supported.
It was fast and fun for a DD but it wasn't fast enough for me. A 12A is stupid easy to wire up and get running in stock form. If you want to go 13B you gotta either figure out the EFI or pay for a carb setup and run a 12A Dizzy.

VW Rotory swap
 

Grannies speed shop carries a transaxle for the swap, and I just saw a bug with a 13bTT and it was Badass! Forget what anybody else says, go with your gut, and go for the HorsePower, Dare to be different!