Advanced Engineering Tech - 3 inch or 3.5 inch exhaust for my 434 sbc

How much hp can a 3 inch exhaust support. My 434 sbc has about 650 hp and am looking to spray about 300 on it, i am trying to keep the car as quiet as possible but i am not trying to restrict it, if you know what i mean. Also what mufflers should i use? Thanks for any help.

I built a 3.5 inch exhaust for my 402, it is making similar power to what you're at but I only ever hit it with about 150 worth at the tires.

I had a set of headers with a 3.5 collector, we ran 3.5 inch pipe to a super 44, just cut the end so it was a 3.5 inch opening, and put some 3.5 inch pipe (cut the end same deal) on the back, so the exhaust exit's in front of the rear tires out the sides of the car.

It was pretty quiet all things considered, and I went as fast with it on as I did with it off, didn't even really change the tuneup much.

I posted on YB a response, but I'll do it here too.

Go with 3.5" and use some Magnaflows.