[Regal Beagle]

I have a 355 SBC AFR 195cc heads with 65 cc chambers, 10.5:1 CR, 600 cfm Edelbrock, XE270HR Comp Cam .495 intake .502 exhaust, 1 3/4 Hooker Headers with 3 inch collectors.
My question is the guy I bought the car from had installed Delta Flow 60 Flowmasters that according to the Flowmaster website are for 6 cylinder cars.
They sound amazing but are they too restrictive and robbing me of any power?

[Guy Hiltz]

What size are they in/out ?? What diameter exhaust pipe & tailpipe ?? I was looking at their online catalog,;
http://www.flowmastermufflers.com/pr...x&cPath=34_145
There are quite a few different sizes.It could be that the ones meant for sport compacts call for 1 muffler,and I'm assuming that you have duals.If they arent necked down a whole bunch,I wouldnt worry about it.You could always contact Flowmaster about this,
Guy

[Regal Beagle]

Originally Posted by Guy Hiltz

What size are they in/out ?? What diameter exhaust pipe & tailpipe ?? I was looking at their online catalog,;
http://www.flowmastermufflers.com/pr...x&cPath=34_145
There are quite a few different sizes.It could be that the ones meant for sport compacts call for 1 muffler,and I'm assuming that you have duals.If they arent necked down a whole bunch,I wouldnt worry about it.You could always contact Flowmaster about this,
Guy

Exhaust is 2 1/4 inch from the collectors back. Collectors are 3 inch.

[Guy Hiltz]

What about where the exhaust pipe goes into,and where the tailpipe comes out of,what are the diameter's here ?? If its 2 1/4 in & out its probably good as is.
Guy

[Regal Beagle]

[QUOTE=Guy Hiltz]What about where the exhaust pipe goes into,and where the tailpipe comes out of,what are the diameter's here ?? If its 2 1/4 in & out its probably good as is.
Guy[/QUOTE
It is 2 1/4 in and out.

[Guy Hiltz]

Well,unless you were to go bigger,(2/12 or 3 inch), all the way from the headers to the tailpipes,this is probably a good exhaust just the way it is.Does it have an X or H pipe in it ??.Theres lots of different opinions on exhaust system size and design.With my 550 hp 468 big block I opted to go with a 2 1/2 Pypes X pipe with cutouts kit,2 Dynomax super turbo mufflers and 2 1/4 tailpipes.It seems to work real good,sounds nice,and I can open the cutouts if I want to go racing.My old exhaust was the same size as what you are running,it seemed to work OK to.
Guy

[Regal Beagle]

Originally Posted by Guy Hiltz

Well,unless you were to go bigger,(2/12 or 3 inch), all the way from the headers to the tailpipes,this is probably a good exhaust just the way it is.Does it have an X or H pipe in it ??.Theres lots of different opinions on exhaust system size and design.With my 550 hp 468 big block I opted to go with a 2 1/2 Pypes X pipe with cutouts kit,2 Dynomax super turbo mufflers and 2 1/4 tailpipes.It seems to work real good,sounds nice,and I can open the cutouts if I want to go racing.My old exhaust was the same size as what you are running,it seemed to work OK to.
Guy

It has an H pipe and really does sound nice as i am always getting compliments on how good it sounds. I just want to make sure that they are not causing any power loss due to being too restrictive.

[Guy Hiltz]

Any power loss as compared to a bigger exhaust is probably minimal,so unless you are going racing,or are looking for every last little bit of power,and it sounds nice and you get lots of compliments,dont worry about it.
Just drive & enjoy !!!
Guy

[Regal Beagle]

Thanks for the insight Guy. Much appreciated.

[454C10]

Flow masters are very loud and don't flow all that great. Sure they are better than a stock muffler for flow but not as good as a Dynomax super turbo that runs about a forth the volume. Hooker Aero-chambers work nicely, flow about 50% more than a flow master at about half the volume (that is the sign of a good muffler, quiet but flows well). Flow master only has a good marketing name but kind of ironic.

[Guy Hiltz]

Originally Posted by Regal Beagle

Thanks for the insight Guy. Much appreciated.

Your welcome !!!
Guy

[Regal Beagle]

Originally Posted by 454C10

Flow masters are very loud and don't flow all that great. Sure they are better than a stock muffler for flow but not as good as a Dynomax super turbo that runs about a forth the volume. Hooker Aero-chambers work nicely, flow about 50% more than a flow master at about half the volume (that is the sign of a good muffler, quiet but flows well). Flow master only has a good marketing name but kind of ironic.

So in your opinion do i need to consider changing the exhaust and if so what kind of result could I expect by opening up the flow out of the back end?

[PapaG]

We used to use 6 cylinder mufflers on each side of V8's many, many years ago. The only mufflers were glass packs and Smitty's. Our thought was if it would be less restrictive for a 6 cylinder, then it would be even better for the V8. We would run as big pipes we could get. I don't remember, but it might have only been 2" or 2 1/2" pipes. But you could also burn out the muffler too Also muffler placement would make a difference on how noise was inside the car. Farther back, less noise. This was all before exhaust became a science.

[454C10]

If you like the sound of your car then you really don't need to do anything. Yes, flow-masters aren't the best but the difference in performance between performance mufflers will not be noticeable on the street.

You could drop a tenth at the track with some Hooker Aero-chambers and run quieter while doing it. Or you could run the same time with some Dynomax Super Turbos and actually have a conversation in your car while it's running. Just giving you some more things to consider.