No cats vs High flow cats.....
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Team Owner
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From: I need a 4 door C6 Z06
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St. Jude Donor '05-'06-'07-'08
No cats vs High flow cats.....
anyone have any dyno numbers???? here is my story......i have an SLP catback. When I put it in I took out the cats.....Made a huge difference in power, but the tips dont stick out past the bumper so I get black all over the back of the car........the only thing I can really do is put back in high flow cats or have someone make extensions for the exhaust tips....
Team Owner
Joined: Aug 2000
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From: San Pedro CA
that tells me your old cats were clogged.
OEM LT1 cats will only snag about 5hp - LPE has apparently tested this.
I would suggest high-flow cats.
before you do that, dyno it with the OEM cats, then without, then with highflow. Just so we have numbers to look at.
Finally, if your engine ever had a bad injector(s), the richness will burn up the cats in no time flat.
OEM LT1 cats will only snag about 5hp - LPE has apparently tested this.
I would suggest high-flow cats.
before you do that, dyno it with the OEM cats, then without, then with highflow. Just so we have numbers to look at.
Finally, if your engine ever had a bad injector(s), the richness will burn up the cats in no time flat.
Team Owner
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From: Athens AL
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On the LT1, its about 5hp according to Lingenfelter's book.
It sure would be nice if you went and got all the dyno results with the old cats and some hi-flows.
It sure would be nice if you went and got all the dyno results with the old cats and some hi-flows.
Drifting
Joined: Aug 2000
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From: Colleyville Texas
Originally Posted by My 95
anyone have any dyno numbers???? here is my story......i have an SLP catback. When I put it in I took out the cats.....Made a huge difference in power, but the tips dont stick out past the bumper so I get black all over the back of the car........the only thing I can really do is put back in high flow cats or have someone make extensions for the exhaust tips....
Pick up 5HP and 10-15LBS of mid range torque taking off the high flow cats and putting on the off roads. Need to bump the fuel pressure up 2-3PSI when I take them off. This is on a 396 LT-1. Alot more noise too.
Pro
Joined: May 2005
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From: crofton maryland
so bad injectors would wreck the cats? the guy i just got my vette from said he just put on new exhaust because the shop told him the cats were bad? so he put a front Y-pipe with the pre-cats and a new cat after that with a new rear Y-pipe.
so i have my injectors checked then so i don't wreck these new cats.
so i have my injectors checked then so i don't wreck these new cats.
Team Owner
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From: altered state
St. Jude Donor '05
Sometimes they go bad due to old age:they clog up. But yes, say you had an injector(s) that wasn't working correctly and dumping excess fuel (running rich), it may clog a cat.
Le Mans Master
Joined: Apr 2000
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From: Manassas VA
Ya know, Im going to tell you the problem with doing a test on this. Lets just say you go test it today with stock cats, tomorrow you test it without cats, the day after you test it with high flow cats, whats it prove? You have 3 dyno sessions to pay for, and whatever the results, there are going to be people who will say, test dont mean anything due to different weather etc. on different days, which may be somewhat true. Exspecially when we are talking 5-15 hp changes. But on a positive note, if you do test I sure want to read about it. 
