Loss of torque after new exhaust
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Loss of torque after new exhaust Hi guys, i'm new to the forum. I have an 01 Trans Am LS1...i got the car about six months ago. I couldn't afford an exhaust system so I cut the exhaust off after the cats then gutted the cats...it was too loud and i got pulled over and decided to put two 40 series two chamber flowmasters on there. So my exhuast setup is this...gutted cats with 40 series flowmasters welded on immediately after then dumped under the seats. After i put these mufflers on there i noticed a significant difference in loss of horsepower and torque. Is it just because these mufflers are too restricting? I am thinking of replacing the 40 series two chambers with some single chamber flowmasters. Do you all think this would get me back to how the car was running when i was running just gutted cats?
You've changed the exhaust pulse of your system the only way to gain the torque back is to put 3" exhaust pipe from the manifolds back for 33" then step down to 2 1/2 for the rest of the system. It's just the nature of chambered mufflers on a true dual set up on our cars. You could change them out with bullet style mufflers and it will act the same as lengthening the collectors on your exhaust and bring the torque back. I've done a TON of research and testing and with my set up I run headers, 3"pipe 33" out then 2 1/2 pipe,x pipe then to 3" single chambered cherry bomb extreeme mufflers. I experienced a huge decrease in torque when I installed my mufflers over the bullets but after extending the collectors all of the torque and more came back. This new set up gained me 2 tenths in the 1/8 mile. If you are running a y pipe then you can still do the same thing. I would go 3" all the way to the y and get a flowmaster y collector. That should fix your problem.
Hi guys, i'm new to the forum. I have an 01 Trans Am LS1...i got the car about six months ago. I couldn't afford an exhaust system so I cut the exhaust off after the cats then gutted the cats...it was too loud and i got pulled over and decided to put two 40 series two chamber flowmasters on there. So my exhuast setup is this...gutted cats with 40 series flowmasters welded on immediately after then dumped under the seats. After i put these mufflers on there i noticed a significant difference in loss of horsepower and torque. Is it just because these mufflers are too restricting? I am thinking of replacing the 40 series two chambers with some single chamber flowmasters. Do you all think this would get me back to how the car was running when i was running just gutted cats?
I would run it back further to gain back some back pressure. With the less restrictive exhaust the car will will pull harder further up the power band. Building off what you have so far and with the minimal supporting mods, the Flows aren't going to hold you back a whole lot. I would definitely move them back as far as possible though.
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Damn, too bad you gutted the cats. Not too long ago they were fetching several hundred dollars for a pair of them. I've still got mine just waiting until the price of salvage cats goes back up.
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