The Stovebolt Site Forums The Shop Area Engine Shop Best pipe size and muffler for 235

I'm at the point with my rebuild of putting in the exhaust and mufflers. Engine is Chevy 6-cylinder 235 with Fenton Dual Intake and Headers. Looking to get an aggressive tone but not sure about what pipe size and brand of muffler would be best choice. I've had some buddies in my local car club that said that I may want to keep the pipe size to 2" or less to assist with backpressure modulation. Any/all feedback would be greatly appreciated. I was initially planning to use FlowMaster Series 40 mufflers with 2" pipe. I'm going to run the pipe straight back through the rollpan that I've installed.

All depends on what you want in the end. Are you going to run your headers into a single or run dual pipes? If dual, will you run a crossover pipe between them? For a classic sound, my preference on old trucks, I would run 1 3/4 dual pipe, short glasspacks and no crossover. For a more modern sound you could go with a pair of flowmasters, still keep the pipe small and use a crossover pipe, or if you want a single go with 2 1/2 pipe and a modern muffler of your choice ( i like Borla myself)

Devin

55 tractor has it right, 1 3/4" pipes and straight through mufflers, probably glasspacks will give the best sound, but it will probably be pretty loud, but some of us old guys like that.

Did the guys in the club tell you where the most skilled/experienced pipe bender in town works? Go visit him and compare his opinion to what you find out here. I went with 2" straight out the back and Dynomax mufflers as was suggested to me.

I also run 2 inch all the way.
Cleon

I'm running 2" also, with Walker Jeep mufflers.

Ditto on the 1-7/8ID-2"OD pipes. No sense of dumping your low-end torque. As for the FlowMasters.....don't think they make them down that small. I had a pair of 40's that I reduced down to work on the 2"OD pipes. Didn't like the tinny sound so went back to the Cherry bomb glass packs. Nice and mellow up to 2300 and then they make that unforgetable inline 6 "chaingun" sound...no crossover.

Dave

Take a look at my setup in the photolink below. Used a one in/two out single muffler. Isn't very loud but does soes sond cool. It's 1-7/8 from the Fenton to the custom collector and 2" out the back of the muffler. It offers just enough back pressure but gives a decent sound with the right muffler. I replaced the muffler to a stock type because it's my wife's truck and she likes it quiter than I do.

Lots of studies comfirm that ideal pipes for these 216 to 235 ci engines for backpressure and gas mileage work best with under 2" pipes, 1+5/8 to 1+3/4" ideal if you can find the pipe. And place your mufflers back as far as you can without crossover. I like the brockman mellotones steelpack mufflers, you can get them made any length. Have also used smittys, borla, flowmasters, jeep etc.

i would think 1-3/4 to 1-7/8'' for backpressure.
your muffler shop guys do this ALL the time. They should know if you go to an older shop w/ experienced techs. i have a mildly hot 292ci and run 2' twin split 3+3 to a single quiet #50 walker to a 2-1/2'' out tail pipe. muff well under the bed.
http://www.walkerexhaust.com/support/exhaust101/inspections.asp
http://www.walkerexhaust.com/support/exhaust101/systemBasics.asp
http://www.walkerexhaust.com/support/exhaust101/productsOfCombustion.asp
it's a hard answer as many will say what's best and you may want a loud (rap~rap) or quiet muffler. if the actual muff is placed directly under the cab you're in or lots o noise as well as down the road exh. issues in the cab, so placement is a thought.
That's ALL up to what you want.