Small Block & Big Block Chevy Specific - Chevelle 396 exhaust size??

Guy at work has one and was asking my opinion on 2.5 or 3.0" system for a stock setup. He was looking at the flowmaster 40 series but not sure on the size for the rest of the system. Since I am unfamiliar with the big block stuff I thought I would ask in here. Thanks for the help.

what hp rating is it? personally, i would go 3" on a big block. that would always leave you room to grow.

If he is going to run flowmasters I would run dual 3" from the collector to the exhaust tips out back an X pipe is also a nice option to throw in there.

It will never need the flow that 3" could provide. If the price difference isnt HUGE id still do the 3". Misewell do it right and have room to expand in the future for a built motor. Otherwise 2.5" will flow more than that motor can make if its stock.

what hp rating is it? personally, i would go 3" on a big block. that would always leave you room to grow.


Not sure just know it is bone stock.

If he is going to run flowmasters I would run dual 3" from the collector to the exhaust tips out back an X pipe is also a nice option to throw in there.



Thnaks guys. I told him what your guys recommendations were and I think he is going to go with the 3 inch and x-pipe setup. Thanks again for the help.

the stock 375hp 396s definitely needed more than 2.5" pipe. that is why i asked the rating of the motor.

3" pipe

Make sure to post photos when it is done!

Make sure to post photos when it is done!



Mit be a while. He is getting ready for a possible frame off. Not sure though. I feel that is way more than the car actually needs but it is not mine. Again I really appreciate the help.

I ran dual 3" in my stock cube LS1, if a motor that small can work great with a dual 3" a 396 BBC will be fine.