Exhaust opinions
 

Hi. I'm ready to order the pipes for my exhaust and wanted some opinions.

My engine's a b18c4 and I have a Garrett gt3076R turbo. The echaust oultlet is 3", and I'm wonrering whether to go 3" all the way or drop down to 2.5" under the engine due to space issues.

I'm only going for about 300hp to start with as it's in a mini. Thanks, Nathan

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damn dude this is sick. what if you split the exhaust into two 2 inch equal length pipes. then you would have the space and the flow.
looks like that intercooler is stickin out past the back bumper anyways. where is your exhaust going to come out.
you could almost just make the muffler part of the downpipe. ive never seen that done before.

There're going to be 3 tight 3" bends taking it down and under the sump in the usual place. but if I drop down to 2.5" at the back of the engine I will have more ground clearance, as I have to keep it down a bit to clear the gear linkages. Not sure whether to y the wastgate pipe into the outside of the first bend of the downpipe, or have it open either...

sound like you could start with a 3" dp and merge down to a 2.5" where your space is tight. then keep that running all the way back because of the space. your wastegate piping probably would be better suited at the first bend of the dp. good luck and keep us posted to what you figure out and how it turns out.

thats the front of the car man just like a civic.
i would just run the 2.5" it will flow plenty for only 300hp. and route your wastegate to the down pipe 18" after the turbo or just keep it open for more performance

Ok, I'll taper it down then. I was thimking of just running a single muffler at the rear. The only thing is that here in england the noise regulations are quite tight on the tracks, some as low as 96db. I'm assuming an open dump pipe from the wastgate will be pretty loud? Has anyone measured the noise from one? Thanks, Nathan

Open dumptube is pretty loud, way higher than 96db. They do make muffling devices for dumptubes though. I know I have seen them.