Catalytic Converter Question

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Trailblazer
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Catalytic Converter Question

Post by Trailblazer »

Is removing the catalytic converter a good Idea? I dont have emissions where I live so that is not an issue. Will I gain power? What are the pros/cons?

Thanks
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Legacy777
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Post by Legacy777 »

I wouldn't bother. If you were turbo charged....that'd be another thing, but for na motors.....they're not hurting anything, assuming they're in good working condition.
Josh

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free5ty1e
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Post by free5ty1e »

Yeah, helps if you have a turbo (as they don't really like or need backpressure) - but with N/A some amount of backpressure is needed, I believe it helps with exhaust velocity...
-Chris
91SS 4EAT stock, 200k mi
91SS 5MT rebuilt engine waiting for a shell
93TW 4EAT, Forester lift, 3" TBE, 11psi, 200k mi
94SS 5MT4.11+rLSD 311k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
BAC5.2
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Post by BAC5.2 »

Well, backpressure is the enemy of exhaust velocity, and the entire exhaust system. You want as little backpressure as possible, with the greatest velocity as possible.


Don't worry about removing the cat. You won't really gain anything other than some sound. If you want the benefits, you can get a high-flow cat, but I would recomend retaining a cat.
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Post by scottzg »

T3h exh. \/aLve$ w1ll b3 c00k3d!

Don't bother.
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dwreck30
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Post by dwreck30 »

But on a turbo car it would not hurt the exhaust valves correct? Would only help right?
- Derek
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free5ty1e
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Post by free5ty1e »

correct. Turbos love free-flowing exhaust systems. Backpressure gives the turbo something to fight pretty much all the time. It's definately not good for spool-up or maximum flow through the turbine.

So, turbo + cat = quicker to burn turbo
N/A - cat = quicker to burn exhaust valves
-Chris
91SS 4EAT stock, 200k mi
91SS 5MT rebuilt engine waiting for a shell
93TW 4EAT, Forester lift, 3" TBE, 11psi, 200k mi
94SS 5MT4.11+rLSD 311k km: RobTune550,TD05-16g @ 18psi,FMIC,3"TBE,Forester lift
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