Exhaust set up?

**jamessr** · 06-18-2007, 06:09 PM

This is my 1st LS1 car and 1st Borla. I bougth the car with the exhaust system already in pace but I'm confused by it. It comes off the block into a Y pipe, Then it runs into another Y pipe right at the exhaust. 1 side goes right out to the tips, then the other goes through the muffler then the tips. Is this set up normal or some shade tree set up. Also a friend of mine suggested I'd get more Hp with a true dual exhaust, dunno wanted to check here 1st.

Thanks in advance

**Transam388** · 06-19-2007, 09:24 AM

The Borla exhaust allows you to adjust sound and performance using block off plates of different size. If you want it louder and generally better performance put the widest plate in or leave empty thus reducing back pressure and increasing noise. When you put the smaller diameter hole cutouts in that pipe it forces more of the exhaust to go through the muffler thus quieting it down and increasing back pressure.

**jamessr** · 06-19-2007, 10:47 AM

Thanks!

**JEB** · 06-19-2007, 11:11 AM

True dual exhaust will give you more power. To get the exhaust out the back and from beneath the bumper in the stock location. You have to run both pipes (2 1/2 inch pipe Max.) down the passengers side of the car. Then over the axle. Then one pipe around one side of the rear tub and one down the other side. Mufflers: I would suggest MagnaFlow mufflers (4 or 6 inch round mufflers) with one located on each side of the rear tub. That makes a great exhaust system with a good sound that is not loud. The MagnaFlows that I suggested are straight through, noise cancelling design. So you get a straight through exhaust flow with out the loudness. Please keep the catalytic converters in place to help clean up the air that we breath.

**mrr23** · 06-19-2007, 02:42 PM

Originally Posted by jamessr

Also a friend of mine suggested I'd get more Hp with a true dual exhaust, dunno wanted to check here 1st.

Thanks in advance

your friend would be correct. i swapped from the 3" borla adjustable to the bassani tru-duals and picked up 15 rwhp

**JEB** · 06-19-2007, 05:55 PM

Originally Posted by mrr23

your friend would be correct. i swapped from the 3" borla adjustable to the bassani tru-duals and picked up 15 rwhp

I picked the same amount of rwhp when I went from that stupid "Y" pipe system and 3 inch pipe to a true dual set up with 2 1/2 inch pipes over the axle and out the back. I used the stock cats., and stock manifolds and still picked up 15 horses at the rear wheels.