Off road Down pipes? Experiences please.

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kcobra

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I currently have a set of high flow catted down pipes and thinking of going off-road down pipes. How bad is the smell and should I just keep my current ones?
 

yaycandy

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I currently have a set of high flow catted down pipes and thinking of going off-road down pipes. How bad is the smell and should I just keep my current ones?

Oh it will smell like gas. Tell ya that as im straight pipes and full catless. Wont smell it in car. Just in the back mostly when cold.
Sure beats cadillac derverter smell
 

Ta2dResqr

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I currently have a set of high flow catted down pipes and thinking of going off-road down pipes. How bad is the smell and should I just keep my current ones?
How bad do classic cars smell? Cars went for 75 years without them and smelled fine. Often without a exhaust sniffer or looking under the car, you cannot tell if a convertor is missing. Motorcycles just started putting them on in the last decade or so.
 

FiveLeeter918

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with proper tuning you can almost eliminate the smell. Like yaycandy said, you can smell it on start up if behind the car but after that I don't notice it.
 

FiveLeeter918

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How bad do classic cars smell? Cars went for 75 years without them and smelled fine. Often without a exhaust sniffer or looking under the car, you cannot tell if a convertor is missing. Motorcycles just started putting them on in the last decade or so.

A lot of tuners leave cat protection on even when the cats are removed and it causes the car to run rich, giving a raw fuel smell. I've ridden in some cars that make your eyes water. Pretty sure we were getting some carbon monoxide poisoning too haha.
 

yaycandy

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Ppe catless dont throw cel for o2s. American racing (livernois) catless pipes do, but a tune can tune it out. I had both, american racing ones first, ppe is larger diameter but bigger isnt always better. I ran my car on a dyno with my tuner since he is local to me and the car actually made more power on the smaller diameter american racing ones. With stock turbos. Probably why they cost more.
 

FiveLeeter918

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Ppe catless dont throw cel for o2s. American racing (livernois) catless pipes do, but a tune can tune it out. I had both, american racing ones first, ppe is larger diameter but bigger isnt always better. I ran my car on a dyno with my tuner since he is local to me and the car actually made more power on the smaller diameter american racing ones. With stock turbos. Probably why they cost more.

you mean PP catted don't throw a CEL? It'd be impossible for a catless pipe to not throw a CEL unless the CEL was turned off in the tune.
 

yaycandy

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you mean PP catted don't throw a CEL? It'd be impossible for a catless pipe to not throw a CEL unless the CEL was turned off in the tune.

The ppe catless never threw a cel for me. Maybe my car is weird, but some other people it never threw a cel for either. Didnt really matter, easy fix if it would have. Just like my stock bov wiring, they can be switched off by Brad for my HKS bov
 

FiveLeeter918

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The ppe catless never threw a cel for me. Maybe my car is weird, but some other people it never threw a cel for either. Didnt really matter, easy fix if it would have. Just like my stock bov wiring, they can be switched off by Brad for my HKS bov

man that BOV switch is becoming a PITA. Finding more and more strategies that don't have that switch activated. We're working with Mike in the other thread on a tune as well and his strategy is unresponsive to the switch. Very annoying and SCT has no desire to fix it since it's not a GT500.
 

yaycandy

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man that BOV switch is becoming a PITA. Finding more and more strategies that don't have that switch activated. We're working with Mike in the other thread on a tune as well and his strategy is unresponsive to the switch. Very annoying and SCT has no desire to fix it since it's not a GT500.

Just zip tie the rear bov to the bar above it like i did for months. Lol. But it worked
 

skyshadow07

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The reason I changed to catted from non was not the smell, the smell was hardly noticeable. It was the sound. The cats cut a ton of exhaust sound. Without them, I was unable to get my car to not be insanely loud at rpms above 25oo.
 

DGrot777

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The reason I changed to catted from non was not the smell, the smell was hardly noticeable. It was the sound. The cats cut a ton of exhaust sound. Without them, I was unable to get my car to not be insanely loud at rpms above 25oo.
What was the exhaust looking like behind the cats? I know you have a side dump lol. Catless sounds pretty quiet when everything else is still on the car.
 

skyshadow07

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I have a side dump, 2-1 with two resonator style mufflers before the convergence. But before I was running the stock piping, minus the first muffler after the 3rd cat and it was very loud.
 

DGrot777

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I have a side dump, 2-1 with two resonator style mufflers before the convergence. But before I was running the stock piping, minus the first muffler after the 3rd cat and it was very loud.
That 3rd cat and muffler keep a lot of the rasp away. I know you can gain some hp deleting them, but for sound purpose those will probably permanently stay on my car.
 

skyshadow07

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I have pretty great sound now with 400 cel cats on custom downpipes going 2-1 after two resonator mufflers then running through oval pipe to dump in front of the passenger rear wheel. The cats helped a ton!
 

kcobra

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Installed off road downs. Literally no sound difference from my high flow catted ones. Very happy. I do hear spooling more. My catted Thunderstorms are now for sale.
 

CCXVI

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I have pretty great sound now with 400 cel cats on custom downpipes going 2-1 after two resonator mufflers then running through oval pipe to dump in front of the passenger rear wheel. The cats helped a ton!


Man I thought I was the only one with a side exit! Mine was right behind the front wheel though
 

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