another freakin exhaust question

okay,, I'm new. ( Cut me a break ). :-)
I own an 85 carrera with 49,000 original miles.
I've read through the last 90 pages of posts. I've read alot about SSI's. I've read that they might be a little restrictive on 3.0 or larger motors. Fact or Fiction? I want heat so headers are not an option, but I do want a little better breathing 3.2. I was planning to use SSI's and a bursch dual inlet/single outlet. Good or bad? (Performance has this setup in their new catalog but you can get it cheaper if you piece it out yourself. The "anderson bible" is on order but won't be here for 7 days.

Welcome! The SSI units may not be optimal above 3.0L BUT they are better than the stock system. It is considered an upgrade to use these exchangers and a free-flowing muffler. Big bore systems have not been well addressed by the aftermarket. I look for this to change with the popularity of 964 and 993 engine swaps (like Jack's).

SSI like heat exchangers and a 2 in 1 out muffler will indeed give you more hp. I wanted such a setup for my 84 3.2, but unfortunately it will make the car more noisy. And that will make my car illegal here in Denmark (max noise allowed is 80db). If you don't have those problems go ahead and get a system.

Hello all
Can anyone give me an idia just how loud
Carrerajim's suggested exhaust would be compared to my stock set up? Would this
sound Kick &$#?
(85 Carrera)

Well here at work we have a gas station just across the street. Not so long ago I heard something unusual on 4 wheels. So typical for me I get up the chair and run to the window. It was a 911 3.0 that had been modified to 3.2 liter, installed with special cams and some other stuff (I went over to talk to the owner because I recognized the car from a car magazine). It also had this SSI like system (danish built and very high quality). I asked how he got the car through the safety/enviroment check every 2 years and he responded "easy". His car was a rebuilt 76 and the noise rules are much less strict for cars older than 84.

It was loud, but it sounded really good. I don't know if you might get tired of it on long journeys?

carrerajim, If I was going to leave my 3.0 83 SC motor fairly stock I would not remove the SSI's and current muffler, I feel that for what I have they would work just fine. In fact I think that even adding PMO carbs the SSI's would work fine on the 3.0 motor. I'm going to use 3.2 heads (cheap way to get ported heads) fairly strong cams, 10.25:1 pistons, 40mm PMO cargs, and dual plug. For this reason I just can't give away the HP gain from headers and I haven't seen any header/heat exchangers that have 1 5/8" runners that work, that I am willing to spend $1500 on. If you are going to fluff your 3.2 and not get radical go for the SSI's.

Randy Jones
1971 911

If you can get around exhaust emissions, SSI's and Dual inlet exhaust is a good system. I've heard too many contradictory information on aftermarket header exhaust. Example, Shop 1, We stopped carrying B&B because there companies quality has been poor lately, (fit and finish, customer service), that is why we sell GHL. Shop 2, I've never heard of GHL. Shop 3 Try Fabspeed, they are better then GHL and B&B.

I'm sure we have been all through this and all it does is leave you confused. SSI's are are proven commodity. They are better then stock. Be careful in later models that you may have to do some custom duct work to make the heater connections. Also if you ever want to get rid of them, you will have no problem selling them. They are no louder then stock if the correct muffler is chosen. Best of luck.

Mikkel - you mean there are no HARLEY'S where you live? You'd probably not dislike that ordinance if you spent a little time in my neighborhood.

I know about the duct mods and also about moving a couple of oil lines. All these scary post about the studs not coming loose or break off leaves me a little shakey,, but I think I can handle it. As for the emissions problem,, I'll just keep the old one and put it back on every 2 years............After I try and sneak through with the catless one. :-)

Hey 89911 -

So what do you think is the correct muffler for the SSI's? Just curious. I'm about to pick up a '79SC and was considering this type of system. However, I don't want it to be much louder than stock. Thanks,

Aubrey

Just go with a stock or close to stock (1974 type) early dual inlet, single outlet muffler. It's when you get into modified dual outlet or aftermarket, (Monte, Mille Miglia) that noise level increases. Some people prefer, (like me to a degree) a bit louder sound

RarlyL8

Motorcycles don't have to come to the safety/enviroment check every 2 years (only cars have to). Motorcycles only need to be checked when changing owners. So the motorcycle owners couldn't care less for noise legislation. We have lots of noisy HDs and even our own danish built Nimbus. My brother has one. It's an aircooled inline 746 cc 4 cylinder. No muffler, just an "empty" exhaust tube. But since it's a 1951 it doesn't need to apply to today's noise rules. You bet the neighbourhood will awake when he starts it early in the morning....

While we're on this - just how much modification is necessary to keep the heater on an '88 if I go SSI's?

Roy M

Folks, I must say that joining this board was one of the best things I've done,,,,,, (aside from buying my carrera).
I look forward to the wealth of info I'll get from you guys (and girls). Who knows,, maybe someday I'll be able to give some advice and answer some questions too.

Carrerajim,
Glad you like it. I was completely overwhelmed when I first joined this site. So much info on Porsches....wow. And lots of good advice from like minded people.

As far as the sound level with SSI's and early muffler goes ... find a stock '73 or '74 CIS car and listen to it ... or ask the owner's that post here about the sound compared to '84 and later Carrera's. I suspect it is a 'richer' sound, and not that much louder, probably a couple of dB's, but certainly NOT objectionable, by any means!

------------------
Warren Hall
1973 911S Targa