I was thinking about getting high flow cats but there are tons of options and I am not sure what type to get. I did search and I just got more confused. There was something about with air or without. I didn't know if I could get universal either. Input and links would be great.

 

I'm going with these, they come with high flow cats :


http://www.troyerperformance.com/cgi...no=122-622100s

 

im in the same boat, i am looking into magnaflow hi flow cats but i dont know which universal cats fit my 5.4 v8.. if anyone has the maggie hi flows on thier 5.4, can you let me know what the model# is???

 

those are really nice but two problems. too expensive and i have the 4.6

 

Magnaflow 94136 is the 2.5" universal cat with 1 O2 sensor bung and the 94139 is the 3" version.

I am running the 94139's with my long tubes and that is what I am putting on my wifes truck with her long tubes. Some exhaust shops will balk at putting those on but if you arive at the shop with them installed then they will do the rest.

 

I think you just need to quit being such a little bich and step up to the plate and get some frappin long tubes and a nice muffler and quit MLK'n your chit

 

I'll man up when you buy them!

 

Honestly, you wont get any noticable changes with high flow cats. All catalytic converters are made the same way and they will still act the exact same way as a factory cat. If your going to spend that type of money then you should buy headers. Im not telling you wat you should do, all Im saying is that all cats are the same and theres no difference.

 

Wrong!,......... I have the Magnaflow 94136 same as Huitt and you can just about see right through the Highflows the stockers where like looking in to a black hole even with a light at the other end, so yes the Magnaflows are better than stock.

 

what is the difference between universal and direct fit?

 

Universal is a cat itself for custom installation, and its much much cheaper.

Direct fit is often the entire Y pipe, or atleast the downpipe and it bolts in directly, buts its much more expensive than buying universal and having a shop install it.

 

Thanks! That is exactly what I was asking.

 

i tested the stock cats on my 03 5.4,under load the backpressure at 5000k lbs under load in 2nd gear was negligible-tested each bank after the 2nd cat on each side-with both readings- they were lower than the single 3" high flow cat reading on my 11 second ta-unless the oem's are acting up cost of replacing them vs the gains on a relatively lightly modded truck isn't worth it-phil