Helix Catted Downpipe GOOD INFO !
#1
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Helix Catted Downpipe GOOD INFO !
Hey all,
I have had a helix downpipe on my car for about 8 months now.
I have dyno'ed on a dynodynamics at 247.9 with it and I thought it was pretty good but I didn't know how useful the cat was until today.
I am doing some apprentice work at a shop that does smogging, and we hooked my car up to the sniffer, and with the helix downpipe at idle the car was at 58 HC and at 2500 RPM no load I was at 89. I don't have the NOx numbers but that is pretty damned good.
I thought I would relay this to you guys since a lot of us are interested in having performance and environmentally friendly cars.
Cheers,
Austin
I have had a helix downpipe on my car for about 8 months now.
I have dyno'ed on a dynodynamics at 247.9 with it and I thought it was pretty good but I didn't know how useful the cat was until today.
I am doing some apprentice work at a shop that does smogging, and we hooked my car up to the sniffer, and with the helix downpipe at idle the car was at 58 HC and at 2500 RPM no load I was at 89. I don't have the NOx numbers but that is pretty damned good.
I thought I would relay this to you guys since a lot of us are interested in having performance and environmentally friendly cars.
Cheers,
Austin
#3
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Originally Posted by VIBEELEVEN
Do you have an uppipe cat? Are other catted dp's and high flow third cats comparable?
I do not know about other catted downpipes but I am guessing they would work ok but I have done no research on them.
High flow catted midpipes are like **** on a nun, they do nothing, if you still have that far too restrictive primary cat, or downpipe then the midpipe makes no difference.
Austin
#7
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I think it was worth the cash, at idle and low RPM's I am still passing california emissions, which are really hard. Now since it is high flow, from what I have heard from people behind me, I get a smog cloud at higher rpms and load. But at least I know I am not a gross polluter, in my mind it kinda makes me drive a little more easy
Austin
Austin
#10
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Car Info: 08 WRX - 401whp/408wtq
In all honesty, I dont think its restrictive at all... Maybe at very low rpm it may show a bit of a difference between between catted and non, but under load, i REALLY doubt it matters... im thinking MAX 1-2 WHP difference... unless a dyno can prove me wrong, logically it just makes sense...
#12
Originally Posted by WRX Rush
But at least I know I am not a gross polluter, in my mind it kinda makes me drive a little more easy
#13
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Originally Posted by SoobAeroDude
Passing the sniffer test is good and all. But wouldn't you still fail visual?
Cheers,
Austin
#15
Originally Posted by WRX Rush
The up-pipe cat is what in the business known as a "pre-cat", so before the 2 main stock cats are heated up, the precat is working to keep emissions low on startup. That being said, at any smog station the car will be tested hot, so that cat is nuetral at that time and does no work. That being said, no I do not have one
I do not know about other catted downpipes but I am guessing they would work ok but I have done no research on them.
High flow catted midpipes are like **** on a nun, they do nothing, if you still have that far too restrictive primary cat, or downpipe then the midpipe makes no difference.
Austin
I do not know about other catted downpipes but I am guessing they would work ok but I have done no research on them.
High flow catted midpipes are like **** on a nun, they do nothing, if you still have that far too restrictive primary cat, or downpipe then the midpipe makes no difference.
Austin