Do high flow cats hurt performance AND how do they effect the exhaust note?
#1
Do high flow cats hurt performance AND how do they effect the exhaust note?
I'm currently catless, but have to pass emissions soon. I'm going to get either the metallic or ceramic Pypes cats and install them in my Pypes H-pipe. I know I'm getting a Brenspeed tune.
Is it even worth taking the High flow cats back off? Do they hurt performance that bad?
Mods are in sig and I have some DR Cams going in soon.
I guess I have a part B question also. How do high flow cats effect the exhaust note? I'm plenty loud right now and wouldn't mind if it went down just a tad, but not much.
Is it even worth taking the High flow cats back off? Do they hurt performance that bad?
Mods are in sig and I have some DR Cams going in soon.
I guess I have a part B question also. How do high flow cats effect the exhaust note? I'm plenty loud right now and wouldn't mind if it went down just a tad, but not much.
Last edited by Bmr4life; 02-04-2011 at 08:23 AM.
#3
6th Gear Member
Clogging and passing/failing emissions aside, consider the performance of hi-flow cats to fall somewhere in between OE cats and no cats, probably leaning more towards no cats, IMO.
#4
If GA is anything like TN all they will do is an OBDII port test and no sniffer. If your test stations are anything like ours you'll get a guy with orange lips in a hurry to get back to eating his Cheetos grab a long handled mirror for the surveillance cameras to half *** glance under you car to check for the cat when he really doesn't give a rip. Before you know it the OBDII cable is hooked to your car, your receipt is printed and your off on your merry way. It's a joke really. But ya better have real cats and no fake shells on your pipes because it will be painfully obvious from the Nascar smell that you don't have them lol.
You may find leaving the cats on smooths out any trumpeting from your exhaust. I thought about leaving mine on but I hate the sulfer smell. When you add cams like FRPP Hot Rods or Detroit Rockers your cats will work very hard. Trust me. With cams your better off running catless because of the extra fuel those cams don't efficiently burn at idle will drastically shorten the life your cats. Metallic or ceramic.
I highly recommend Brenspeed with your mods for both a performance and emission tune. They worked perfect for me last year.
You may find leaving the cats on smooths out any trumpeting from your exhaust. I thought about leaving mine on but I hate the sulfer smell. When you add cams like FRPP Hot Rods or Detroit Rockers your cats will work very hard. Trust me. With cams your better off running catless because of the extra fuel those cams don't efficiently burn at idle will drastically shorten the life your cats. Metallic or ceramic.
I highly recommend Brenspeed with your mods for both a performance and emission tune. They worked perfect for me last year.
Last edited by timmbo; 02-04-2011 at 08:46 AM.
#5
I looked it up online.
All 1996 and newer vehicles will receive a three-part inspection:
An OBD test to check your vehicle’s emission control performance history.
A fuel cap inspection to check for adequate seal.
A visual inspection of the catalytic converter to check for tampering or removal.
If an OBD test is unable to be performed on a vehicle, it may be necessary to perform a Two-Speed Idle test (TSI).
I read that as NO sniffer.
Thanks for the replies. Sucks that I'll have to hack up my H pipe to add cats and buy another one to go back to catless.
Just had a thought. After I cut the H-Pipe to clamp in the cats. Maybe I can have a muffler shop fab a pipe that I can clamp back in in-place of the cats. That make sense?
All 1996 and newer vehicles will receive a three-part inspection:
An OBD test to check your vehicle’s emission control performance history.
A fuel cap inspection to check for adequate seal.
A visual inspection of the catalytic converter to check for tampering or removal.
If an OBD test is unable to be performed on a vehicle, it may be necessary to perform a Two-Speed Idle test (TSI).
Thanks for the replies. Sucks that I'll have to hack up my H pipe to add cats and buy another one to go back to catless.
Just had a thought. After I cut the H-Pipe to clamp in the cats. Maybe I can have a muffler shop fab a pipe that I can clamp back in in-place of the cats. That make sense?
Last edited by Bmr4life; 02-04-2011 at 09:26 AM.
#6
I looked it up online.
I read that as NO sniffer.
Thanks for the replies. Sucks that I'll have to hack up my H pipe to add cats and buy another one to go back to catless.
Just had a thought. After I cut the H-Pipe to clamp in the cats. Maybe I can have a muffler shop fab a pipe that I can clamp back in in-place of the cats. That make sense?
I read that as NO sniffer.
Thanks for the replies. Sucks that I'll have to hack up my H pipe to add cats and buy another one to go back to catless.
Just had a thought. After I cut the H-Pipe to clamp in the cats. Maybe I can have a muffler shop fab a pipe that I can clamp back in in-place of the cats. That make sense?
#7
I have two Pypes HF cats which I took off my car after I installed my m90 for sale if you want them. I bought them from brenspeed. They were on my car for 8 months with 3k miles. I paid $189. You will have to weld them on. Shipped $100 if interested.
http://www.brenspeed.com/cvm10k.html
http://www.brenspeed.com/cvm10k.html
#8
I have two Pypes HF cats which I took off my car after I installed my m90 for sale if you want them. I bought them from brenspeed. They were on my car for 8 months with 3k miles. I paid $189. You will have to weld them on. Shipped $100 if interested.
http://www.brenspeed.com/cvm10k.html
http://www.brenspeed.com/cvm10k.html