1974 911 exhaust change

[tucson 911]

Another question Guys, I want to change my exhaust out, of coarse stainless and a better throaty sound. Where I live in Tucson (outskirts) we don't need cat converters. should I remove them when putting new exhaust on and which mufflers have that good sound, engine is a 3.0. Will I gain a wee bit H.P from no cats. All this is foreign to me, no pun intended. First Porsche, I'm just used to my 69 charger and 70 mach1. Thanks guys for bearing with me, love this car. Triple black with air.

[75 911s]

Your car did not originally include catalytic converters. In 75 They introduced a rudementary emissions setup which included the Thermal reactors in California. I think 76 and 77 all US cars had them. Your 74 exhaust (if original) is actually very good. Unless you have money burning a hole in your pocket or the existing ones have been changed or rusted out, then keep them. Take them off, jet coat them and reinstall with new studs and hardware if you want. (studs are a whole different story - they break easily, so removing your setup can lead to a lot of pain and expense)

Start by posting a picture.

You want the throaty sound, convert your muffler to a 2 out (since it's already a 2 in via the 74 exhaust) or bolt on an MK 2 out. No need to change the desirable Heat exchangers out.

BTW in Arizona, pre-75 cars are exempt anyway, and of course you are outside of Tucson city limits so you are fine too. A cop can still cite you for being too loud though unlikely.

[tucson 911]

Thanks Duane, Like I said all new to me and no rust at all Az car, might change muffler will post pics soon.

[Tony V]

Duane,
OP states the '74 has a 3.0 engine. It may have been installed "as is" with the cats intact.
If so, muffler would be a 1 in and 1 out.
Pictures would tell the story.

[dfhtrhjn]

Yea +1 on keeping the '74 headers with heat exchangers if you have them on there. 2-in 2-out muffler is the way to go if you want the throaty sound.

I have an M&K and it's awesome.

Prior to that I punched out my stock muffler and made it 2-in 2out. Much quieter at idle but screamed at high rpm.

[75 911s]

Well twist ending, I skipped over the part where the car had a 3.0 swap. Thanks Tony! So we don't know what heat exchangers he has on there atm. Either way SSI heat exchangers would be great imho paired with a M&K 2 in one out or 2 in 2 out for really loud.

[tucson 911]

Hello Guys, Thanks for the info will show pics of underneath of car this weekend.