Remps

Hey, So I'm kinda new to the whole rotary engine thing, and just I picked up a 79 rx7 with a 12a 4 speed manual. I got the car from some farmer who had it sitting in a bush for a couple years. extremely low km, horrible body. Anyways my whole plan is to strip it down to nothing and make it into a cheap stock car for a local league. Well its already stripped to nothing, and while stripping we noticed my exhaust runs a single cat, but is rusted out. So What my question really is, is there a safe way to "straight pipe" a rotary? I'm looking for a cheap fix so the car runs decent. from what I know rotary's need back pressure to run.

KansasCityREPU

iTrader: (9)

Use a header and do away with the cat.

Remps

Also, after the down pipe there is a Y, and a smaller size tubing runs the whole length of the exhaust and stops before the muffler tips. theres no cat, muffler or anything along the line. Is this pipe for the back pressure. Ill post some pictures next weekend when I have it off the ground again. My buddy that's helping me with my build, he has a 85 and he said its completely different than his exhaust.

KansasCityREPU

iTrader: (9)

I know one tube supplies air from the air pump to the cat to help it burn the fuel. Not sure about the long tube that goes stops just before the muffler. It is not for back pressure that I know. The 1979 has a really heavy exhaust manifold called a Thermal Reactor.

Check out the Racing Beat site for replacement exhausts. They are not cheap, but are the preferred replacement if using a header.

Remps

Well the goal of the build is to spend as least as posible i picked up the car for $400. And cage seat harness and window net kit will run around $600. So exhaust wasnt something i was budgeting for. Im leaning towards cutting the cat out and welding in a replacememt pipe. Run all stock exhaust including muffler. Would that be fine for the engine? The car had 84xxx km but the car its self was rusted out. So the engine is probably the only good thing about the car

RGHTBrainDesign

One hell of a build here... Please delete and move this to general.