I have no cats on the mustang, it's loud enough to wake the dead, and the stink still doesn't stop people from riding 1" from my rear bumper...

I don't buy that you won't gain performance out of it; every vehicle I've done it to - mustangs mostly - has gotten noticeably better mileage and gained ~10-15 hp. On the current mustang, replacing the 6 cats midpipe with an "offroad" aluminum prochamber shaved ~60 lbs of weight and gained 14hp on the dyno.

 

Look at the size of the V10's catalytic converter. Comparing it to a Mustang isn't apples-to-apples

 

I don't quite understand your point, the CAT on the V10 is more restrictive... so one would figure that you'd gain even more horse and mileage removing it from a V10 over the Stang.

I don't know about my hp, I don't Dyno my truck, but I do know that my fuel economy went from 9MPG highway to 13MPG highway when I chopped the CAT and cleaned the MAF sensor. That is a pretty huge improvement, nearly 50%.

 

I didn't notices any increase in mpg or performance when changing from the stock cat (which was like new with only 20k on it) to a Dynatech. Didn't notice increases in either with the cat and catback exhaust combined neither. Best mpg back when stock and now (tune, headers, cat, catback) on primarily highway are about the same at 14.75mpg.

So I want to see the before and after numbers of a V10 truck on the dyno. Same day, same dyno properly functioning OE cat vs aftermarket "hi flow"vs cat delete. Then I'll make my decision. Too many people are succeptable to placebo affect of extra sound vs actual power increase.

Its called capacity and the OE V10 cat has a hell of a lot more of it than the OE Mustang cats do.

There is your mpg gain. Assuming the removed cat was not clogged or partially clogged. I hope that mpg gain is consistant also. Not just a once or twice best case senario.

 

Sure, my tests aren't scientific. However my old 460 was about the same gain, 10MPG to 14MPG. (never cleaned the MAF on that)

Overall, I probably pick up 2MPG on mixed driving, but hey that is a lot in these beasts.

I'd love to see the numbers you speak of also. But I don't even know where I'd go to Dyno something.

I do know this, if the CAT muffles the sound more than the muffler does, I figure it must be very restrictive. A CAT delete is probably even better for the V10 than it is for other high displacement engines since the V10 likes to wind up. @4,500 that engine can scream and really benefit from the lack of back-pressure. It probably doesn't make much difference at the low end.

I still have the stupid stock Y-Pipe, can't wait to put true duals on there, need some coin to get it done. I want to do headers at the same time. I just had my right manifold studs fixed a couple weeks ago, now the left one is coming undone. Instead of fixing the stock crap I'm going to wait a little longer for some cash for some Gibson headers, a True-X and some Magnapacks

Oh yea, my MAF sensor wasn't really dirty, barely any visible difference from what looked like before and after cleaning.

 

I deleted mine for testing, no power gain and no mileage gain. I generally only tow with it, so no gains going up grades pulling 3800-4000rpm. The only thing I got out of it was crap from the wife complaining of the smell.

 

That was one of the reasons I didn't get a 7.3 (cough cough)

 

couldnt smell worse then driving my old 65 chevelle with dual straights or my 65 chevy pickup with straights coming out infront of the back tires right??

 

Probably won't smell as bad as that.
It'll have some bark, that's for sure. I like stepping on the gas a little bit when I turn the key, it really comes alive.

I chopped off my CAT mostly to experiment with sound. I know my V10 will never sound as good as my old 460ci did, but I think I can get it to sound pretty great with an X-Pipe and true duals. I am still torn on muffler choice. It's going to be Magnapack or Super44. They are both about the same price.

 

It's actually pretty stinky, but not as bad as my 500hp NA 347" sbf with 3" "duals" Dr gas x pipe and dynotech mufflers dumped in front of the 4 link. It makes 4" of vacuum at idle and burns 3/4 gallon per quarter mile, pretty stinky.

It'll make it louder if that's what you want, I put an old dynomax in it's place to keep my sanity.

 

So what about just rebuilding an exhaust? mine is gonna start getting holes in it from time and age...its got rust flakes and i dont like the look, the truck looks great, not a spot of rust, just a dent in the rear quarter panel from a bycylist.....

 

I grafted a cat back of 6.0L on to mine when I did the cat delete, no gains from any of that stuff. The new exhaust systems are decent, some grade of stainless, this one was 3.5". 3" is plenty for the v10.

 

try swappng to these,. i've used them on rodz i've made for sale
Cherry Bomb | CATALYTIC CONVERTERS

 

Nothing I have removed the cats from EVER gained performance and id love to see some dyno sheets on that. It's the sound that makes u feel like you've gained performance.

To the OP, do what ya want, I'm sure u have already. Just remember its just asking for something to go wrong or spend more money down the road IMO

 

performace and cat/cons don't equal one another,.however,.there are a few with less back pressure ,magna flo, cherry bomb ect,. the magna flo directs are part of the header and though pricey,.are a popular choice with rodders,.but truth is cat backs with cast iron headers and stock cat/cons work best for street trucks