whats the true answer (cutout question)
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From: Kopavogur ,Iceland
whats the true answer (cutout question) i have done many searches but cant find the answer. what gain range does a open i pipe cutout gain on a otherwise stock car? the only numbers i seem to find is the gains on aftermarket VS cutouts
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From: England
By-passing the stock muffler will allow better exhaust flow. This means more power. I would think in reality you would be looking at ~5-8rwhp at the most on a stock car. A modified car is a different ball game though. A good catback will flow as well as the piping so a cutout is pretty pointless on the correct setup. Stock piping is a restriction at 2.5", the cutout can not by-pass this.
If you plan on a decent catback or duals, a cut-out becomes quite redundant as a performance mod, although they can be quite good as a volume control device if you want a more stealthy everyday exhaust.
If you plan on a decent catback or duals, a cut-out becomes quite redundant as a performance mod, although they can be quite good as a volume control device if you want a more stealthy everyday exhaust.
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From: Kopavogur ,Iceland
thats exactlly why i got mine. im just wondering what the gains are when i open the cutout and if there is any loss of tq seeing that i still have the stock y-pipe and cats
Originally Posted by 300bhp/ton
By-passing the stock muffler will allow better exhaust flow. This means more power. I would think in reality you would be looking at ~5-8rwhp at the most on a stock car. A modified car is a different ball game though. A good catback will flow as well as the piping so a cutout is pretty pointless on the correct setup. Stock piping is a restriction at 2.5", the cutout can not by-pass this.
If you plan on a decent catback or duals, a cut-out becomes quite redundant as a performance mod, although they can be quite good as a volume control device if you want a more stealthy everyday exhaust.
If you plan on a decent catback or duals, a cut-out becomes quite redundant as a performance mod, although they can be quite good as a volume control device if you want a more stealthy everyday exhaust.
Originally Posted by lilbuddy1587
Hate to sound negative, but you couldnt be more wrong. People have gained 20+rwhp OVER the 4" mufflex setups with a cut-out added in the i-pipe. Regardless of how well a muffler flows, a cutout will always be better because it BY-PASSES IT. Don't believe it ? Do a search.
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From: England
Originally Posted by lilbuddy1587
Hate to sound negative, but you couldnt be more wrong. People have gained 20+rwhp OVER the 4" mufflex setups with a cut-out added in the i-pipe. Regardless of how well a muffler flows, a cutout will always be better because it BY-PASSES IT. Don't believe it ? Do a search.
Why not try a little research yourself. The sticky on induction/exhaust would be a good place to start, try post 13 onwards by David Vizard.
You also need to remember that on most setups a cutout will affect the exhaust pressure wave, this more likely the cause of gain on some setups as opposed to exhaust flow.
Also ther more highly tuned a vehicle is (i.e. HP level) the more affect it will likely have.