CR00SS

I just finished my home made borla setup, well sorta, I used a dynamax turbo muffler on one side and open pipe on the other. The car sounds great at idle but has a little to much rasp going down the road at about 2000-2500 rpm. I was just wondering if anyone had used an insert to quiet down and reduce rasp on a similar setup like mine. If you have a soundclip please post. Also I had thought about putting a bullet in the I pipe to maybe absorb the rasp. I don`t really mind the loudness mainly the rasp. I don`t have but about $40 in this setup so far since I used the stock dual tips, but I may go with true duals with aerochamber mufflers if I can`t get rid of the rasp. Any advice appreciated!

dlandsvZ28

Yes...inserts will reduce rasp. I've done both ways. First with an insert in the pipe just in front of the rear axle and then with a 4 inch ceramic coated pipe with a CC insert inside from Car Chemistry.

After reading that inserts supposedly reduce hp I removed it and now just run a Magnaflow catback with no cats and lt's. But rasp is back and annoying.

I replaced the Borla with a Magnaflow. The Borla was much worse with rasp than the Magnaflow.

I'm going to insert a low restriction bullet or chambered pipe next to see if that will help. Can't go with true duals because I can't find anything that will fit with my chassis mounted Spohn TQ and drive shaft loop.

Worse case will mean going back to low restriction cats if the chambered muffler won't work.

Ric

Where'd you read that the insert make you lose hp? Not puffing up, just want to know.

Redneck Z

iTrader: (3)

I've also seen some dyno's floating around here showing big hp losses.

dlandsvZ28

It's been awhile and a search probably won't pull the thread since it's a few years back just after inserts came out, but I recall it was MTI who did a back to back test and lost something like 50 hp. At the time I was surprised that Car Chemistry didn't refute the test, but no response that I recall.

It would be any easy test. Dyno before and after. Stick the tube in and dyno and then dyno again without one.

Honestly, I don't think you would loose 50 hp because you don't gain 50 by removing the stock exhaust and replacing with a hiflow catback system. So 50 hp is a lot to lose just because of the insert. That test suggests that an insert is 2 times more restrictive than the stock system, since realistic gains installing a good catback probably gets about 15-18 hp.

As for me, I pulled the coated 4inch Car Chemistry tube because I didn't have room for it behind the Street Pro electric cutout I installed. It was too long. Pic is here of the Street Pro cutout > http://pg.photos.yahoo.com/ph/dlands...&.dnm=3512.jpg

It's for sale if you want it. $50 + shipping.