Hey all,

I was wondering if I put high flow cats on my truck....will it make it any louder??? and also what kind of performance increase can I expect?? thanks!

--Cowboy

 

A buddy of mine runs high flow cats on his 96 f150 and it didnt make a signifigant amount of difference. If you want to go louder i suggest you save up for something worthwhile. high flow cats especially on newer vehicles seem some what pointless to me. Performance wise it made his truck run a little better, but you can expect that with any upgrade from stock. Oveerall, I suggest not getting a high flow cat you truck is too new and it will void your warranty if you havent already done so.

 

But would one help on a '91 302 w/ a Flowmaster system...?

 

For early 90's and other earlier models high flow cats will provide a signifigant performance improvement. I think that they are pretty worthless on newer models because of different emissions parts put in trucks by the maker and because it voids warranty. If you have an aft-cat system i would say save up for some headers because they will give you worlds of improvement beyond that of a high flow cat, but if you already have them then i thinhk a high flow would finish off your system quite nicely

 

On my 98 F150 4.6 I removed all four catalytic converters and added a flowmaster single in dual out exhaust. It did make a significant diffrence in performance and the sound is REALLY loud. This removal didnt even trigger the engine light and a year later i still havent gotten a problem. But i am going to redo the front pipes and add two high flow cats. Its going to lower the sound significantly but will create some backpressure. But im quite sure its not going to remove that much performance. It will just take care of more sound than a resonator will.

 

cptslewis,

I want to remove the cats but wouldent I get killed by the emmission testion??

--Cowboy

 

If you completely remove them yes you will get killed on emmisions because there is a visual check too. or atleast in some states there is.

 

Jon right If their is a visual check then their is no way to pass it. But what boggled me was that all new computers are set up with emissions limitations. If your computer is running properly and you dont have the cats in shouldnt you get a light??? I didn't so im assuming that with the other engine mods ive done it keeps it sorta within limitations. Please no one shoot me down on this one.... I believe in protecting the enviorment but that howl when i get on the gas w/o the cats is Cool... Especially when it send my exhaust fumes into the civic next to me.

 

I just installed a cat-back and was talking to a muffler guy about hi-flow cats. He said it would definately open the sound up more because I would be moving from 4 cats to 2 hi flows. As far as performance goes he said realisticly I would see about 10-12 HP.

 

From what I understand is that ford got in some big trouble a while back for emmisions but now thier engines are really clean. when all i had done to my truck was a 50 serties catback and a K&N FIPK I got tested and it was like 1.xxx of an allowable 3000 something carbons so I think even with no cats you might still pass but not a visual test. which is why i could never do it because VA has visual checks.

 

AUBronco40,

I have the same problem with the visual test but.....you think I could gut the cats and put them back on so it would LOOK like I had them one but they would be hollow??? Just a thought.

--Cowboy

 

I bet that would work just gutting them...I have some friends who did that. they got away with it. probably as long as it doesn't look like they've been messed with your are probably in good shape. But luckily for at least the tiem being I odn't have to worry about any of that. Its nice to live in the south.

 

Will a muffler shop remove your cats??

 

Very doubtful, unless you get lucky. It is illegal to remove a properly functioning catalytic converter, so they can get in trouble with the Feds if they get caught removing them (unless they are non functional anymore and are being replaced with a new one).

 

really?