downpipe

Headers, cats, uppipes, downpipes, midpipes and mufflers.

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the_watts10
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downpipe

Post by the_watts10 »

ok first of all i running no exhaust after downpipe and was wondring if the cat inside could burnt out and was wondering whats the upperhand to installing a catless downpipe? hp wise
ej22t hybrid, 3.5" downpipe, Gl turbo intake/desnorkel 9psi DEAD
Legacy777
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Post by Legacy777 »

Running a catless downpipe usually reducing back pressure and improves turbo spool.
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SubaruNation
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Post by SubaruNation »

you need to have some sort of exhaust.

otherwise i think bad things can happen like backpressure and your car can spit out oil
Zach - Legacy Frankenstin
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Boostedballs
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Post by Boostedballs »

SubaruNation wrote:you need to have some sort of exhaust.

otherwise i think bad things can happen like backpressure and your car can spit out oil
Nope, turbo cars do not need back pressure. The lower the pressure downstream of the turbine, the better. The turbo works on pressure difference. High inlet pressure and low outlet pressure will make the engine rev very fast.

A naturally aspirated engine (N/A) isn't quite as simple. You need back pressure to control exhaust flow in the heads, based on your cam profile and many other factors.
Air-to-Water Intercooler, VF-39, 550 injectors, AEM FIC, stainless race header, 3" stainless exhaust, 75hp Nitrous, 150psi H2O injection, intake mods, stock: long block, 4EAT, ecm.
SubaruNation
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Post by SubaruNation »

oh, good to know!

so if your car is turbo charged, you can just take apart your exhaust and nothing will happen?
Zach - Legacy Frankenstin
93forestpearl wrote:Keep up the good work. You'll never know what you are capable of unless you push yourself.
the_watts10
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Post by the_watts10 »

yeah about the whole backpressure thing i found that out today ive been runing not exhaust besides the downpipe and just but a catback on it today and it is really spooling up like its suupposed to and its a alot faster
quieter but faster!!!
ej22t hybrid, 3.5" downpipe, Gl turbo intake/desnorkel 9psi DEAD
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