Anyone know what the best brand or even specific model of cat is the best for exhaust flow? My engine is a stock 305. Pipes are 2.25in. Just wondering if anyone has a daily driver that that still has to go through emissions like me. Im sure anything is better than the 30yr old cat I have now XD XD
I use 2 Magnaflow spun cats which are rated for California compliance but the smallest they come is 2.5". Magnaflow does have an offset spun cat that is 2.25" ......
Thought I'd share: I couldn't pass smog this year because of my high emissions levels. So, I replaced my stocker with a Magnaflow (pn 332015) CalCat. I didn't notice much of a performance gain, though my emissions numbers were reduced significantly (some were in the zeros).
I initially was going to go with Walker 80822, but the Magnaflow appeared to be bigger in size.
Magnaflow also makes pn 332016. It's the same size body, but the in/outlets are 2.5" vs the 2.25" in/outlets for pn 332015.
Pontiacgp's suggestion might yield better flow, which might help boost performance for these smaller engines .
The Fluffy kind or the flat face kind 😛 But my dad uses magnaflow spun cats same as Pontiacgp but i would advise ditch the stock system and go with dual exhaust jegs has a nice kit with mufflers for cheap if your in the states
It's illegal to install dual exhaust in a car model that never had it as a factory option. Even with dual cats, a dual exhaust is still illegal if it is non factory. The best flowing cat would be the wide mouth cats that came on the SS models, the non SS models got smaller mouth, poorer flowing cats that used different style hookups. If you need to still pass inspections, then your only option is a factory SS single cat, split exhaust setup. Part of the 1990 clean air act.
It is quite easy for inspectors to check the exhaust system, they either use mirrors mounted on a long handle and rollers or drive the car over a floor mounted video camera and view it on a monitor.
It's illegal to install dual exhaust in a car model that never had it as a factory option. Even with dual cats, a dual exhaust is still illegal if it is non factory. The best flowing cat would be the wide mouth cats that came on the SS models, the non SS models got smaller mouth, poorer flowing cats that used different style hookups. If you need to still pass inspections, then your only option is a factory SS single cat, split exhaust setup. Part of the 1990 clean air act.
It is quite easy for inspectors to check the exhaust system, they either use mirrors mounted on a long handle and rollers or drive the car over a floor mounted video camera and view it on a monitor.
Fresh oil change and take it out on the e-way and run it hard getting it good & hot (would use card board in front of radiator to get it as close as I could to 210 deg) take it for the test - never shutting it off and keeping hot, helps burn off the hydrocarbons.
GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
