High-Flow Cats?
Thread Starter
|
Senior Member
Joined: Nov 2002
Posts: 104
Likes: 0
From: Birmingham, AL
High-Flow Cats?
My '01 5.4 Screw has 4 cats, seems like overkill. My Wife used to have a Cherokee, when the single cat broke up and started rattling on her Jeep, I had it replaced with a high-flow cat. Made a huge difference. Has anyone replaced the stock cats with high-flows on their F-150? If so, how has it worked out?
BTW, I am running a Gibson SISI cat-back.
Thanks.
BTW, I am running a Gibson SISI cat-back.
Thanks.
Technical Article Contributor
Joined: Jun 2002
Posts: 10,511
Likes: 10
From: Under the flightpath of old ORD 22R
Mike,
The high flow cats can make some difference in performance, but it is usually when :
Headers are being added
True duals are being installed.
To take apart the system to change out the cats for high flow cats, and then re-install the stock Y pipe and a SI/SO muffler, is a lot of work for little gain.
This is kind of like doing a MAFS and fuel system upgrade with leaving the remainder stock, it would help but there are better ways of obtaining gains before going to this extent.
Before installing high flow cats, some ideas ( if you don't have them done already ) are :
FIPK
Change SI/SO system to true duals with a X pipe.
Electric Fans
Pulleys.
This is if the stock cat is still working correctly, if there is a problem with one of them, then by all means, high flow cats are the only thing to use in the replacement.
If you have this completed, and still want more, it is time to look towards headers ( with the reburn ) true duals with X pipe and maybe a MAFS and injecotr fuel rail / pump upgrade.
Next step after that is a S/C.
Hope that answers your questions.
The high flow cats can make some difference in performance, but it is usually when :
Headers are being added
True duals are being installed.
To take apart the system to change out the cats for high flow cats, and then re-install the stock Y pipe and a SI/SO muffler, is a lot of work for little gain.
This is kind of like doing a MAFS and fuel system upgrade with leaving the remainder stock, it would help but there are better ways of obtaining gains before going to this extent.
Before installing high flow cats, some ideas ( if you don't have them done already ) are :
FIPK
Change SI/SO system to true duals with a X pipe.
Electric Fans
Pulleys.
This is if the stock cat is still working correctly, if there is a problem with one of them, then by all means, high flow cats are the only thing to use in the replacement.
If you have this completed, and still want more, it is time to look towards headers ( with the reburn ) true duals with X pipe and maybe a MAFS and injecotr fuel rail / pump upgrade.
Next step after that is a S/C.
Hope that answers your questions.
Thread Starter
|
Senior Member
Joined: Nov 2002
Posts: 104
Likes: 0
From: Birmingham, AL
Thanks, I was wondering if the High-flows would make as much difference as they did on that old jeep. I have an FIPK and have given serious consideration to S/Cing. mmmmmm Power!
Senior Member
Joined: Aug 2000
Posts: 1,623
Likes: 0
From: Lockport, NY USA
The only reason you gained hp on the old jeep was because the old cat that you replaced was restricting the exhaust. The factory cat can flow more exhaust than your truck is capable of putting out, so unless you are doing intake mods and headers its a waste of money. If you do get a high flow cat make sure it is designed for a truck. You can get cheap generic cats that say highflow, and they work on cars, but they are too small for trucks and will actually make you lose power.
-Jon
-Jon
