high flow cat z28 1999
#1
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looking at fitting speed engineering y pipe to magnex quad rear exhaust on 1999 z28.
Was thinking of getting single cat fitted after the y as mine is lowered..
Anyone done this and is there room?
I was thinking magnaflow 3.5" 59920 and using 2 sets v bands connectors/clamps.
Did you loose much hp?
thanks
Scott
Was thinking of getting single cat fitted after the y as mine is lowered..
Anyone done this and is there room?
I was thinking magnaflow 3.5" 59920 and using 2 sets v bands connectors/clamps.
Did you loose much hp?
thanks
Scott
#2
TECH Senior Member
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A single cat after the Y-pipe will literally do nothing but restrict exhaust flow. Cats need to be a certain (high) temperature to burn the unburnt fuel that goes through them, that is why they are always in front and right after or almost right after the exhaust manifolds or headers. Putting them that far back they will never reach the needed temperature to burn the fuel.
If you are worried about clearance then either don't run cats, run bullet style (small) high flow cats and a proper Y-pipe that tucks up nicely or raise the car up some (suspension geometry on these cars isn't nearly as functional after lowering more than 1.5" - you will actually have improved handling and ride at 1.2in lowering compared to being any lower than that).
I have a catted Y-pipe from stainless works and it actually tucks up better than the stock one in most areas.
If you are worried about clearance then either don't run cats, run bullet style (small) high flow cats and a proper Y-pipe that tucks up nicely or raise the car up some (suspension geometry on these cars isn't nearly as functional after lowering more than 1.5" - you will actually have improved handling and ride at 1.2in lowering compared to being any lower than that).
I have a catted Y-pipe from stainless works and it actually tucks up better than the stock one in most areas.