hey guys,
Recently i acquired an electric cutout for a very reasonable price, and im looking to weld my own exhaust together.
My plan is to have a full 2.5" exhaust, mandrel bends, with a resonator and a muffler, with a cutout after the resonator and before the muffler with piping on the other side of it bending around the battery box and then out the back.

so essentially, im looking for recommendations on a resonator that will provide enough back pressure to loose as little torque as possible after flipping the switch,
and a muffler to pair it with so day to day the exhaust is relatively quiet (no louder than a jcw or miltek for example)

Thanks!

 

I don't want to start a forum war but back-pressure as you are describing it is essentially a myth (post header, header design is a different animal). You won't lose power with less restriction, it just makes more noise so people think the engine is working harder.
Many people have had luck with Hushpower mufflers. MBRP or Vibrant makes a good array of resonators. I would get under the car, measure the lenght/width mufflers you can fit and go from there. Probably could get a 20+" resonator then run a hushpower in the location of the stock muffler.

I installed a MBRP resonator on my S2000, 24" iirc and it made a huge difference. They are also pretty cheap.
Link showing the internal design
http://www.thoroughbreddiesel.com/mbrp/resonator.htm
Link showing 2.5" version
http://www.autopartsdealer.com/25in_...2046580-g.html

 

I have a custom exhaust 2.5" + custom header 4-1 + high flow cat on my R52S.

Resonator: flowmaster hushpower II 18''
mufflers: vibrant ultra quiet resonator







Here is a sound clip when I was doing lapping : http://www.youtube.com/watch?v=AK_s3BZSE84

Hope that helps you.

 

Sounds really loud. Is that your thought about it or is it just the video?

 

I'm really interested to see how this turns out, sounds like a really cool idea!

 

It's loud because the high flow catalyser. Plus, I pushed full throttle.

Otherwise, on city driving is not too loud. I work for the provincial police (the law is strict against loud exhaust) and I tested drive my car with police officers and they told me: "You know, if I hear a MINI Cooper S like this one, I don't know I will intercept the car. It's loud but could be normal for any european sport cars. Perharps, if it was a Honda Civic, I will pull over."

I got that exhaust installed before to have the header. With an OEM exhaust manifold, that system sounds like the JCW/Miltek (or just a little bit louder, couldnt even notice it).

 

heavy metal, any idea on what tips you used?

 

Vibrant 3" （single wall, angle cut)
http://vibrantperformance.com/catalo...roducts_id=105

Don't go larger than that. In my area, police officiers guess if an exhaust is modified by looking the size of tips, then they pull you over to verify if the exhaust is legal. My police officiers co-workers confessed to me, by looking to the tips, they would never knew the exhaust is not OEM.



It took 8hrs of work to complete the exhaust.

 

where i live, there are no state inspections, and cops do not care about modifications or exhaust noise level.
there are well over 15 "street legal" as in they have a tag and drive everywhere, that have over 1000whp, so large exhaust tips don't matter much.

 

Sometime, I would like to live in USA... where car modifications never end.

 

... except in California :P

 

hey everyone, how does a 17" hushpower II resonator and a flowmaster 50 series deltaflow sound? think it will be quiet enough?