wow...thats crazy

 

I went out and bought a stock cat back w/muffler for $50 ...got my buschur cat back in the garage bubble wrapped up.

Have yet to regret the transition. No bother from cops

 

This was my first Question. I could stock exhuast and old cat robbing this much HP no problem. I imagine over a 3tbe with test pipe you would only gain a couple hp.
Still thinking about doing this. I installed one on a friends STI and it sounded mean.

 

An O2 dump is much less effective. It doesn't help spool (it's closed before full boost is reached) and, once open, it doesn't free up the exhaust downstream of the turbine wheel. On high boost applications, the gain is even less because the wastegate (the dump) stays closed longer.

 

I've always wanted to see actual results from a cutout. Thanks for posting! This might be a good option for me.

 

Nice compare.

what cat are you running if any?

increased backpressure is the result of less boost. turbo cant spin as freely = less boost.

 

Not cat...it's installed where the test pipe would be...right after the downpipe

 

I bought a QTP cutout welded into a testpipe on the forum a while back to use with the stock catback but I sold it to have MAP build me a 3" catback with a Varex muffler that they as I wanted to drop weight over the stock piece. Only downfall is that the car is powerless with the valve closed.

 

I recently went From my vishnu 3in (which is suppose to be on the quiet side) back to stock, and I will not be going back! Was thinking of doing a custom piece that replaces the stock cat with a ypipe and a sound performance boost activated cutout.

 

well it makes sense, since it allows the turbo to run more boost because of almost non-existent back pressure...

Nice comparison chart!

 

Might have to schedule some Dyno time to see how the cutout compares to the Buschur 3" TBE that I had when I hit 439whp o 93oct @ 28psi

Added pics to the first post of the installed piece and controller.

 

It'd probably be a good idea to have a open map, and a closed map. Now that would be a good comparason.

 

I have my second map tuned for highboost 33psi with meth 500+whp

Ill see how close the loads are from Open cut out to closed and try and tune the closed.

 

I've always driven my car around with a full straight through exhaust and external dump, I've never been pulled over for exhaust noise (must be that liberal west coast state lol ), I also don't do any pulls around cops though lol

 

I'm really thinking of a boost activated cut out but 400+ for the SP cut out seems kinda steep when I could just try to make one my self for 1/4 of the price.

Check out post 12 of this link. Is not as clean looking as the SP cut out but it should do the job.
http://www.team-integra.net/forum/16...exhaust-s.html