Not sure what to do about exhaust system?

[ShadowsFa11]

Right now my car is at the shop with an RB25 being installed. The motorset came with the stock down pipe from the R33 but I am not sure what the piping diameter is (I think 2.5?). I don't know if I should buy a new downpipe and get a full cat-back exhaust, or keep the stock down pipe and get what ever exhaust system will fit. Opinions?

[Darius]

I'd be less worried about having a downpipe made to fit an aftermarket exhaust than I would be about having the turbo elbow clear the steering shaft. Make sure that works first, buy an exhaust, and fab up a pipe to connect the two. Don't forget a bung for a wideband sensor too.

[gawdzilla]

what most people try to do is get the catback exhaust for your chassis. then all you have to worry about is making your downpipe clear and the correct diameter, and placing it so it matches a generic catback. if you don't like it, buy another catback for the body and it's an easy change.

[ShadowsFa11]

Is it ok to run an open downpipe for a few weeks while I save up money for a cat-back?

[Darius]

I wouldn't do it for extended driving since the exhaust will be blasting against the bottom of the car. It could damage the undercoating of the car. Plus, if the exhaust doesn't outlet behind the cabin, exhaust fumes will make their way up into the car. Not good. Do you HAVE to drive it without an exhaust? Why don't you just wait until you can source an exhuast and get a new downpipe fabbed up?

[RustspecS13]

I have a RB20/25 down pipe for sale. It fits the stock elbow that comes right off the turbo and goes to a stock location cat/test pipe. I made it myself and it tucks pretty close to the chassis.

I'm using a Mckinny mount kit and stock subframe in my s13, and that's what its made for. I'm not sure how well it would fit with a mount kit that uses a r32 subframe.

The only reason why I'm not using it is because I upgraded my turbo and I cant use it. Its made with 3/8in Vibrant flanges and its 3in diameter, with a mandrel bend, and the piping and flanges are all Stainless steel.

I don't know why you'd need a cat back made as the cat back is universal to any engine. The only thing that changes is the turbo elbow and down pipe. Basically between the engine and test pipe/cat.

I really doubt the R33 down pipe will work, and even if it will there might be clearance issues. A custom cat back would be more money then a custom down pipe, as the cheapest one on e bay is $160 plus shipping and a shop to modify it.

Good luck on the swap!

~Alex