which flows more?

[LWATSON]

Didnt know where to put this thread, figured dealing with exhaust flow it would be fine here. I'm thinking of making a bypass for my exhaust. Its a little loud with the charger I'm running so I thought about putting the stock muffler or cat back on. If I use the stock muffler it will take the place of the banks muffler. If I use the cat I'll just put it in front of the banks. Then I'll put a Y in front of the muffler and or cat an E cutout then Y back in behind the muffler. So which flows more stock muffler or cat?

 

[Chevy1925]

If I were to guess (cause I don't know either) I'd say the cat flows more

 

[Balindir]

I don't know for a fact, but I would sure think a muffler would flow better than a cat...

 

[Chevy1925]

the way i see it, a cat is a flow through design due to its purpose. a muffler (specially stock) is designed to reduce sound, to do this baffling is usually installed making the flow of the exhaust turn every which way to dissipate the noise.

could be wrong but thats my thinking. the stock cat may be overly restrictive even though its flow through

 

[Balindir]

Yea I see what your getting at, and that makes a lot of sense. I guess my thinking is, its easier for the exhaust to go around, instead of through... But i could be dead wrong.

 

[LWATSON]

It would be easier to just add the cat in front of the Banks muffler and I ran it like this when I was at around 500 HP. I installed a cat delete front pipe and saw no increase in performance. With the bigger charger and more power now it would probably hurt performance thats why I'm going to bypass it for the track and playing around.

 

[Chevy1925]

I wanna do a 4" e-cutout on mine on the downpipe somewhere, i just dont know how i wanna run the pipe for it. kinda wanna do something cool with it

 

[mackthehack]

What about trying a "high flow" or high performance" cat with your exhaust currently on the truck?

 

[gmduramax]

The stock muffler would be the most restrictive I think. But running the cat cuts down on alot of noise, so I'm thinking it's restrictive also.

 

[SSchmi5519]

magnaflow makes high flow cats

 

[LWATSON]

I need to check out the Magnaflow stuff, I bet there cats are expensive. Also I wonder how hard it would be to install some kind of switch on the excelerator that would open the cutout when you went over 75% throttle?

 

[Fasttoys450]

Check out FTE I am thinking about one withe my single stack set up the are suppose to cut down a lot and they are great people to deal with I called with a lot of questions and they answered all of them

 

[SSchmi5519]

I need to check out the Magnaflow stuff, I bet there cats are expensive. Also I wonder how hard it would be to install some kind of switch on the excelerator that would open the cutout when you went over 75% throttle?

I used to have one, IIRC 280.

 

[blk smoke lb7]

I dont have much oppinion on either but i can tell you on a race day Corey and my self were going to the track and we were trying to lighten his truck up some so we took the exhaust of installed just a 90 with a flange on it and 45 degree elbow to dump out.the result was the truck was noticably slower for some reason.Didnt think back presure effected turbo diesels but i must be wrong.We reinstalled the full exhaust and the truck just flew again.

Not sure i would do a dump.JMO

 

[LWATSON]

I dont have much oppinion on either but i can tell you on a race day Corey and my self were going to the track and we were trying to lighten his truck up some so we took the exhaust of installed just a 90 with a flange on it and 45 degree elbow to dump out.the result was the truck was noticably slower for some reason.Didnt think back presure effected turbo diesels but i must be wrong.We reinstalled the full exhaust and the truck just flew again.

Not sure i would do a dump.JMO

Funny you said that, I had an 02 totally stock, I installed a 4" Banks system on it and lost 3 MPH off my trap. I tested and tested, put the stock exhaust back on and got the 3 MPH back. I did this all in a 4 hr period. I was told on the forums that I didnt see what I saw and was a complete idiot. I plan to bypass the muffler and cat and Y back in behind the muffler hopefully this wont have an adverse effect on power. I'll run it both ways at the track and see if it makes a difference.