High Flow Cat vs NO Cat
03-15-2009, 05:57 PM
#1
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High Flow Cat vs NO Cat
Here is the set up I plan to put on my car and I want to know if the set up would sound better with a cat delete or a high flow cat?
OTT 3in Exhaust without resonator, CTI Down pipe, and JBP Vortex Header.
OTT 3in Exhaust without resonator, CTI Down pipe, and JBP Vortex Header.
03-15-2009, 06:06 PM
#3
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I think a cat costs you like 3 horse power, and makes your car not sound like ass. Plus, I dont care what anyone says about global warming, if you are putting less **** into the air, its better.
*note, this post is my opinion, so if you want to bitch at me, have a nice cup of STFU
*note, this post is my opinion, so if you want to bitch at me, have a nice cup of STFU
03-15-2009, 06:07 PM
#4
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Thats what I was thinking. It's not like the High flow cat will pass smog. So you save money and get 2 more horsepower. But my main concern is how it would sound. Do you have experience with catless cobalts?
03-15-2009, 06:14 PM
#5
I think a cat costs you like 3 horse power, and makes your car not sound like ass. Plus, I dont care what anyone says about global warming, if you are putting less **** into the air, its better.
*note, this post is my opinion, so if you want to bitch at me, have a nice cup of STFU
*note, this post is my opinion, so if you want to bitch at me, have a nice cup of STFU
hydrocarbon gasses(spec of 300ppm)mine was 70.
Carbon monoxide(spec of 1.5% give or take .5%) mine was 1.8%.
Nitrogen oxide(spec of as close to 0ppm as possible) mine was 7ppm.
Carbon dioxide(spec of 10% and higher) mine was 17%
Oxygen levels were actually a little high but i have an exhaust leak so that would explain that and its not like oxygen is hurting the environment.
i would still fail emissions for not having a cat though. lol
03-15-2009, 06:35 PM
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Everyone goes cheap and wonders why their exhaust sounds like ****.
03-15-2009, 06:44 PM
#12
It maybe of interest to you and your needs.
03-15-2009, 08:20 PM
#15
are you kidding me? a cat only robs a couple ponies? on our cars its more like 10-15, friend with a vette removed the cats and gained over 30 dyno proven horsepower. air flow through a cat is ridiculously hindered. for power, you want your exhaust as free flowing as possible, while keeping air velocity up. having a cat greatly restricts both. im not vouching for the sound however. most dont like it and im not fond of it. but to say the cat only takes 2-3 hp is misinformation
03-15-2009, 08:21 PM
#16
are you kidding me? a cat only robs a couple ponies? on our cars its more like 10-15, friend with a vette removed the cats and gained over 30 dyno proven horsepower. air flow through a cat is ridiculously hindered. for power, you want your exhaust as free flowing as possible, while keeping air velocity up. having a cat greatly restricts both. im not vouching for the sound however. most dont like it and im not fond of it. but to say the cat only takes 2-3 hp is misinformation
03-15-2009, 08:25 PM
#17
if you dont believe me, just look at the inside of a catalytic converter and tell me that doesnt restrict airflow
i wish i would have dynoed my car before hand, but after just a catless downpipe i put down 245hp and 212 tq. granted it isnt saying much because i dont have an initial dyno. 15 hp is pushing it, but its definitely more than 2-3
i wish i would have dynoed my car before hand, but after just a catless downpipe i put down 245hp and 212 tq. granted it isnt saying much because i dont have an initial dyno. 15 hp is pushing it, but its definitely more than 2-3
Last edited by ssyellowss; 03-15-2009 at 08:25 PM. Reason: Automerged Doublepost
03-15-2009, 08:25 PM
#18
looking and providing airflow #'s are 2 totally different things. you talk about misinformation, and then go on to say that a cobalt will gain 15 hp by changing the cat. now it's your turn to provide proof. and flow #'s are a better indicator of power gains. dyno's are pretty much worthless for accurately determining hp, especially when you're talking about less than 10 hp range. you can dyno 10hp more or less on the same day with nothing done differently to the car.
03-15-2009, 08:32 PM
#20
03-15-2009, 08:36 PM
#21
well the numbers i have already are ~500cfm for a 3" downpipe with a high flow cat and then ~725cfm for the 3" catless downpipe. i would think all other compenents were the same as tested, but i am not sure so im not going to fight tooth and nail to say these are 100% true. i wasnt trying to start anything or any arguments.
03-15-2009, 10:49 PM
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