Guys,
I've got a 94 F-150 w/5.0/AOD and plan on trashing the back cat because of it's 2.25" diameter tubing and running a cat-back from the front cat because it has 3" outlet tubing on it. I can't decide which cat back to go with. I know I'll have to lenghthen the tubing to reach my fwd cat.
Is the Summit 3" cat-back system any good? Does it use a cheap turbo muffler or is it a good high flowing muffler? Summit wasn't any help when I asked. Is it by chance a Flowtech or Flowmaster muffler? I know they market Flowtech headers as their "own" brand.
What about the Flowmaster ForceII cat-back? I know I'll get a free-flowing system with them. How loud is the ForceII? I don't really want a droning/noisy system. I drive 70+ miles to/from work every day, and my wife and son ride in there sometimes too, so I would like something rather quiet as far as interior noise goes. What series muffler does the ForceII system use?
I thought about making my own with an off-the-shelf muffler, but it'd cost more than a cat-back in the long run.
What about the Gibson stuff?

Thanks,
John

 

Isn't the O2 sensor in between the first and second cat? How are you going to work around that? Plus, if you live in a state that does smog checks, removing a cat will make it illegal.

I replaced my exhaust from the second cat back. Had it done at a local muffler shop with a good reputation. Used 2-1/2" pipe and a 50 series Flow Master with dual outlets and finished it off with two 3" stainless steel end caps. The 50 series Flow Master is louder the stock (but then what isn't?), but not so loud that you couldn't carry on a normal conversation inside the cab.

 

Well... Summit's catback systems sure are low cost, BUT you get what you pay for. I had their 3" system and I wasn't too impressed with the quality. The piping was mandrel bent and seemed fairly decent in construction but the system as a whole didn't match up right and looked horrible. The muffler that came was a turbo style and was poorly constructed... I put the system on April 2002 and took it off in September and the damn thing was rusting itself out pretty bad. I'm talking a large pile of rust flakes/chunks when I shook it. Soundwise-- I kind of liked the tone but it was fairly quiet...

I'm a Flowmaster fan!! I have the 40 series on my truck and its great. I think the interior resonance would not be to your liking tho. Possibly get a 50 series or 50 series delta-flow.

That said... If you live where you can get it custom done, I'd just fork out money for a muffler of your choice (research the exhaust forum... lots of GOOD info there) and have the shop custom fab you good mandrel bent tailpipe.

Post this in the exhaust forum as well. Guys there can give you some other good opinions.
Ray

 

My O2 sensor is mounted a small H-pipe between the 2-tubes that go in the first cat. I only have one. My truck also has mass-air as well. Maybe this is why it only has 1 O2 sensor.

John

 

my friend put the flowmaster cat back system on 95 dually with a 460 in it. im not sure what series the muffler was but it is very quiet. he said he recieved little or no milage or performance gains though. i replaced my stock muffler with a flowmaster 40 series on my 96 4.9 and i can not tell any difference in performance either. i think it was a waste of money. i should have just replaced the muffler with a straight pipe it sounded better and i would have saved $80.00.

Please do not post in capital letters.

 

I did some searching around yesterday and I guess I'll go with the ForceII system. It uses a 70 series muffler which according to Flowmaster is their quietest muffler. I think it'll have a little sound and alot less restriction.
I think the main restriction on these truck is the second cat. Think about it (using my truck as an example), the exhaust comes down from each manifold as 2.25" pipes. They go into my first cat and come out a 3" pipe (one 3" flows the same as 2 2.25's, do the math). That 3" then goes into the second cat and comes out as a 2.25" and into that big restrictive stock muffler. If you think about as a whole, half of the flow is getting restricted by the second cat, the small diameter tubing coming out of it, and the stock muffler. The truck is choking.
So, IMO, and only IMO, a cat-back is useless unless the second cat it trashed, or you keep the same diameter tubing from the y-pipe all the way back as to not restrict flow.
I'll keep the first cat on there just for the smog inspections and such. It shouldn't be clogged or anything, the truck runs perfect. I'm getting about 15 mpg now. I'm just trying to get a little more mpg out of it, and a little sound. Also I plan on putting a small cam in it down the road as well as a bedcover to try to coax a little more mpg out of it.

Thanks for the replys,

John

 

Look into Dynomax cat back systems. I have one of those and it's quiet, but still has a deep sound to it. It's my understanding that Dynomax's out flow Flowmasters too.

 

[updated:LAST EDITED ON 03-Jan-03 AT 04:15 PM (EST)]http://www.discountconverter.com/converters/ford/index.htm

This is a replacement y pipe that has the O2 sensor and only one hi flow cat.

PN# 9302 (look at photo by clicking on part # on the cat page)

 

i have bassanni headers and exhaust on my truck and it sounds pretty decent. especially with the KandN FIPK

 

Right now I have a single 3" flowmaster 40 series with a single outlet on my 94 F150 5.0. It sounds nice. Not too loud, but very noticeable. Just my $.02.