Random Tech High flow cat with stock exhaust??

[Andy Szkutak]

Well, the other day i went to rev up the trac and i heard a noise that sounded like little marbles jumping around from underneath the truck. I took it in to get looked at and it turns out my cat (idk which one) has went bad and the "honeycomb" inside has fallen apart, which is the noise i hear. I'm going to need to replace the cat, and i was wondering if the high flow cat from wayne will work with the stock exhaust?? I may have to replace everything after the cat anyways, but will it work fine with just the stock muffler, etc?? I was thinking about puting a delta 40 or delta 50 muffler on and putting a pipe through the resonator with a pipe out the back which switches to dual tips like the mountaineers have... Anyone have this and can give me a price idea and where to buy???



Thanks

Andy

 

[Rodger Tellefson]

Just to check that if you are not aware of it there are 4 (four) cats on our ST's. :blink: Had to have all four of ours replaced last spring to the tune of $1200 which was the OEM + labor.



I personally would not go with anything less than a FM 50 SUV so that you don't pull the exhaust out to quickly which could burn a cylinder.

 

[Andy Szkutak]

Thanks for the input,



Is it possible to eliminate the precats? I was told that only one of them seems to have the problem, but i am not aware of which one it is..I'm going in with it next saturday to get a look and an idea of what needs to be bought.. Will the delta 50 be loud at cruise speed?



Thanks again

Andy

 

[Rodger Tellefson]

You'll have to get input from Todd Z on whether you can eliminate the precats. I have heard the 50 SUV, which is more mellow than the FM 40. I went with the FM 70 Big Block because I wanted the quietest sound on the market.

 

[Fudged Undies]

You can get rid of the pre cats with no side effects. That's what the y-pipe does. The hi-flow cat at this point may be problematic since there seem to be issues with our sponsor/vendor. You could just use an aftermarket hi-flow cat from any vendor like magnaflow and have it replaced at your local shop. Assuming the main cat is actually the problem. As for the resonation at cruising speed, I think you'll be pretty happy with the 50 and cat replacement.

 

[EddieS'04]

I think the cats have a 8yr/80k mile federal mandated warrantty...check the owners manual..I could be wrong..

 

[Rodger Tellefson]

We don't have a problem with Explorer Express, do we? I would use EE over HIA.

 

[Andy Szkutak]

I appreciate all this help..What if it isnt the main cat and just a precat? Will i get a CEL? Could i just put a y pipe in there?? and then leave the stock cat if its not the main cat that is gone? and then add a delta 50 suv? Would i get a noticable performance increase ?



Fast eddie, i am at 118k...I wish it was 8 yr unlimited miles lol Thanks though!



Thank you all

Andy

 

[Dallas Starr]

The only cat you have to keep is the one directly after the pre cats. You can eliminate the first 2 (PRECATS) and the last one.

 

[EddieS'04]

California is the only state that requires the pre-cats, TMK..Here in Texas I have had muffler shops build me a new y-pipe, for other cars. Some would prefer to do it only if the pre-cats are damaged, others dont care. All you need to buy is two 14mm thread nut for the O2 sensors. They can re-use your flanges. The cost would alot less than the random-tech y-pipe. You would still get a decent bump in HP over the pre-cat y-pipe.