so i dont actually own an rx7 but i wrenched on one for the first time today and it was great fun. These cars are built so nicely and logically. I do own a 74 super beetle that is getting an 12A for x-mass. My biggest worry is exhaust, I have much less space to work with and thats not good. my plan is a merged header, with a 90deg bend (now running parrell with the rear bumper, stock VW location) into a sielencer (rx7 specific) and then into some kind of muffler. A guy at work has a new stock muffler for a first gen he said he'd sell me cheap, or I have heard that a SS magna-flow will hold up. Any one have any ideas to help me with this or any recomendations on mufflers? I would like the exhasut to be quieter at normal revs but bark a bit when i open her up. Anyway just in case your wondering heres a few details on the conversion:
-81 RX7 motor 90,XXX miles
-KEP adaptor and flywheel
-heavier 1700lb pressure plate
-electric fuel pump and a regulator
-1.5" copper tube to get the coolant to the front of the car then some standard rubber rad hose
- 36"x11" jeep cherokee radiator
-2 10" electric cooling fans with thermostat
-twin oil coolers running in paralell
this is the plan at least and i have all the parts together less the adaptor. This all may seem like a lot of work and money but it takes a lot more to build a reliable 100+ hp aircooled motor... reliable being the key word.

 

A good website for your question is www.shoptalkforums.com

Click on their Conversion Perversions forum, and ask those guys.. you'll get answers from guys who have "been there done that".. or may be doing that right now. Just doing a search on that forum for "rotary" will turn up some interesting reading. Good luck. I've ridden in a Super Beetle with a 12A, and it was a blast!

 

This sounds like a really project. I can't wait to see the progress, do keep us posted!

Sorry..... can't help ya with your exhaust question.

 

yeah I'm all over the shop talk forums already, Damn good people and a lot of help. I just figured there would be a greater wealth of knowledge and experience out here. And I'm documenting everything i do, well almost, didin't think is was a good idea to bring the digi cam into the junk yard. I'll be doing doing a ot of the work when i get off for the long thanksgiving weekend. I'll get some pics up.

 

Anything straight-though will be pretty loud when off idle, especially with headers. Just make sure whatever muffler you get that it is built to handle the heat. Full throttle EGT's can exceed 1400*F. Fiberglass-packed mufflers won't survive long. Stainless steel is the packing of choice. If you go with a baffled muffler, get one that is built well, otherwise the baffles will break when the engine backfires (which is very likely to happen).

Good luck on your project, it should be a fun one!

 

racingbeat sells a presilancer. they do a good job. you can use one of them then have a muffler after it. would tone it down a bit.

 

I think the rotary in a V'dub is a match made in heaven.
I would like to do the same project, but in a giah.

 

that would be MY project, a 13b in a '70 ghia.

I got a bunch of 1 7/8" stainless tubing and stainless steel wool and figure to weld up my own 'glass'packs.

4 port 13b from a cosmo
kep adaptor
bus tranny
holly 4 barrel + RB manifold
aluminium jetta radiator + air conditioner evaporator + aluminium heater core.
eccentric shaft fan on jetta, electric fans on evap & heater
radiator in whaletail - ducted to engine fan
dual oilcoolers (don't know exactly where to put them yet :p )

 

really my dream is a 914 with a 13B turbo. Imagine the handeling of the 914 with all that power and the sound and the revs. oh man There is a guy at work that keep trying to sell me his '73 914 and its sooo tempting. The 914s will already out twisty the 911s of the time, they just didnt have the huevos to live up to what a Porshce shoudl be. I think a 13B turbo would make up for any short commings of the VW type 4 engine that the 914 was stuck with. And you can't deny that chicks dig a Porsche. After workin on the RX7 I have to say that I would probably ditch my 86 turbo Z for one any day. Thanks for the recomendations guys!