Exhaust Mods? Stop Here!
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You'll loose some Torque, but you'll gain HP. It basically balances out the power curve. I've driven SSEi95'* car, with his pulley, colder plugs, stock airbox (i know) and 3" exhaust to magnaflow. It wasn't missing anything on the bottom end IMO 
Get a 3", and fill it with a small pulley, and good CAI and you're good.
Get a 3", and fill it with a small pulley, and good CAI and you're good.
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Ya, I don't know if it works with a Bonneville, but there is a 3" RT downpipe and cat that would go well with some nice headers. The only problem is, headers are incredibly expensive. Porting the headers would be nice, giving a significant gain, but it will still have the 2.5" size. Going to 3" would be nice for the overall effect of modifying the car, but it would cost a ton.
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Originally Posted by Sol
Ya, I don't know if it works with a Bonneville, but there is a 3" RT downpipe and cat that would go well with some nice headers. The only problem is, headers are incredibly expensive. Porting the headers would be nice, giving a significant gain, but it will still have the 2.5" size. Going to 3" would be nice for the overall effect of modifying the car, but it would cost a ton.
Actually, MNCGP had a deal at their last meet/mod day for downpipes, and it'* MUCH cheaper with an exhaust shop doing it.
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I think a common misconception on these boards is that we can't open things up. Frankly ALL engines benefit from better breathing. Whether you like the effect personally or not is your own decision.
There'* no reason our 3800 doesn't do this either. Yes you need some backpressure. But 3" with a high flow cat, and some muffler will most likely work for anyone.
There'* no reason our 3800 doesn't do this either. Yes you need some backpressure. But 3" with a high flow cat, and some muffler will most likely work for anyone.
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My headers made a huge difference.
Well worth the cost of a set of new tires.
I laid a twin patch of rubber today all the way thru 1st gear with almost a full load of passengers...................I really do need a set of new tires.
Well worth the cost of a set of new tires.
I laid a twin patch of rubber today all the way thru 1st gear with almost a full load of passengers...................I really do need a set of new tires.
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Keep in mind that we've had SC and NA cars try to go 3" in the past, and they lost low-end torque. In one case, they scrapped it and went back to 2.5". You have to have a ton of mods to support 3" exhaust and keep the low end. 2ksb can do it, and our better modded SC'd cars like his. I would even doubt my own car with 3" exhaust. I don't have enough flow to support it.
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Originally Posted by willwren
Keep in mind that we've had SC and NA cars try to go 3" in the past, and they lost low-end torque. In one case, they scrapped it and went back to 2.5". You have to have a ton of mods to support 3" exhaust and keep the low end. 2ksb can do it, and our better modded SC'd cars like his. I would even doubt my own car with 3" exhaust. I don't have enough flow to support it.
He still had plenty more then I do now. That'* with a pulley, STOCK airbox, so it'* basically being choked on the front end.it all depends on what you're after
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From: Land of Lincoln
Originally Posted by willwren
So comparing just the more popular (here in Bonneville Land) 2 mufflers, Flowmaster and Magnaflow, The Magnaflow is 1% more hp (3.5 hp over Flowmaster), 0.2% better in torque (basically the same), 14% better in flow, and virtually the same sound, except for a 1db quieter level at WOT.
It doesn't sound like much, but it is an edge. There are alot of people that won't laugh at a 3.5 hp difference.
It doesn't sound like much, but it is an edge. There are alot of people that won't laugh at a 3.5 hp difference.