So for my 1977 350 Monte carlo, I need to replace a portion of the exhaust, and figure that im just gonna pull it out and drop in a performance system. Im thinking, headers, new cat, new cross member, all piping replaced, and duel exit with tips. I had a few questions, first, what's a good muffler/cherry bomb setup that will allow for a nice deep start and not be obnoxiously loud when im driving at normal speeds, also should I weld and do install myself or just go the safer route and have it done ? Also any similar upgrades or any cool exhaust tips tricks are welcome, looking for a knowledge boost as well. Thanks

 

if its the original 350 and youre not looking to do anything else to the motor i would get a set of small diameter long tube headers and 2.25" piping going to flowmaster 40 series mufflers. id avoid any of the cherry bomb glass pack mufflers i think the sound like a cow mooing on at cruising speed and are obnoxious at full throttle. if you plan on building the motor up this is the time to get some larger diameter long tubes and a 2.5" set up, with 40 series flowmasters. on welding if you know how to weld and youre confident than why pay some one to do it. if not pony up the cash and have someone do it. summit and jegs both sell butt cheap aluminized mandrel bent set ups for your car. im running one on my 80 and it was definitely a good buy. just ordered the mufflers i wanted in the same size as the ones that came with the kit. id also ditch the cat altogether.

 

Live in cali, I have to have a cat? And ya that's about what I was thinking of doing if I don't just get a kit. Why 2.25 insted of stock 2.5? Thanks for the response

 

Stock on a 77 is a single 2" exhaust 2.25" dual will be a big inprovement.
I don't remember the emission laws for cali on classic's.
I bought mine in san diego

 

Is the car still in California, and what is your setup for your exhaust?

 

2.5" would probably hurt performance on your car. the smogger 350s werent exactly world beaters. compression is low, camshafts had no lift/duration, the heads dont flow, and the manifolds, single exhaust, and cat dont help. opening up the exhaust will help a lot, but you dont want to over do it to the point where you kill back pressure, and make the car slower. being loud is only cool when you can back it up. you dont want the car to be obnoxiously loud, and then get blown away by fits and civics.

 

So 2.25 is a good size for my 350?

 

Too small if you stay single ok if you run duel.
The stock is super restrictive 2" single.

My Monte hasn't seen Cali in about 11 years.
I got a set of long tubes with 2.5" duel pipe an some super cheap muffers(all i could aford at the time).Your crossmember will be the biggest problem it's only a single hump you'll need a new one there about 250-275 or modify the current one or bend the pipe under the cross member.I bent mine under any muffler shop can do it.Modding the cross member isn't hard but takes more to do.
As far as cats go mine is long gone here in New York the Monte is emissions exempt.

 

Hmm ok. I don't really know how I would run the headers to the cat and do duel exhaust, which is pretty much the only reason I haven't already done this

 

they sell double hump cross members, and any shop should be able to run the cats after the headers. does cali just do a visual inspection to see if you have cats or do they smog test it? they may also sell emission legal exhaust set up for that car. if its just visual get a pair of cats from the junkyard and hollow them out.