Exhaust advice for new 68 owner

[stuntmanmike]

Hi All, just picked up a 68 911, 2.0. It's my first so reading up on as much as I can.

One thing I thought I'd ask the experts on - it has a very loud exhaust system, fun around town but too much for long trips and I expect to make some. The seller said it's a "Dansk RSR-style muffler" and you'll see in the photo that the stock exhaust hole has been welded shut.

Are there any relatively quiet options that I can work with without opening the exhaust port back up? I dont mind the dual pipe look, just the sound is a bit too much. Thanks in advance. Mike

[silverc4s]

The "Sport Exhaust" is just a loud solution - seems to be even moreso on the smaller displacement engines. I had one on my 2.2 S for a while and it was really raspy & especially loud at higher revs.
Now I have on on a 3.2 liter with SSi's and it is not nearly so loud. If you wanted to quiet it down, perhaps cutting it open and adding some dampening material like fiberglass or whatever is used to baffle sound normally, then resealing.
One very common 911 owner sickness, is a muffler collection...

[stuntmanmike]

Forgot to mention, the car has SSI Headers and Heat Exchangers with the Dansk RSR-style muffler. Any suggestion of a quieter muffler that will bolt up? Thanks

[304065]

Stock Dansk or used factory Leistritz. Quiet, nice back pressure for torque.

[Joeaksa]

I have a Dansk stainless steel muffler on a 3.6 engine and its still pretty quiet.

The stock "banana" style muffler is not too bad and bolts up to the SSI system.

Joe A

[gumba]

I made these baffles that slip in the tips for our twin center pipes race muffler. The perforated steel i.d. is 1". I wrapped it with stainless steel wool. Depending on how tight you wrapped it would determine how loud it wa, to an extent. Originally on our 2.8, then on the 2.4S street motor. On the dyno I lost 5 h.p. Went from intolerable to tolerable on the street.

[stuntmanmike]

Do you think the dual pipe non RSR Dansk would be noticeably quieter, and does it bolt to SSIs? Thing is I need the outlets below the bumper as the stock exhaust port is welded shut. How about the Monty muffler for early 911s? Thanks for all the help.



Pelican Parts - Product Information: 616-111-010-05-M350

[D8design]

Layout - Master

[ttweed]

Originally Posted by stuntmanmike

Thing is I need the outlets below the bumper as the stock exhaust port is welded shut.

I had a custom dual outlet on my '68 originally that was too loud for our events at Qualcomm stadium (93db limit) so I installed a stock muffler. Since I am running a FRP rear bumper on my R-look car, it had no cutout on the driver side for the muffler exit either. I simply cut off the exit pipe and rotated it downward and rewelded it--a simple mod to allow running the stock (quiet) muffler without having to cut the bumper for clearance.

Original dual outlet:



Modified single outlet:




TT

[stuntmanmike]

Hey, the exit pipe cut/modification seems to be a good route. Do you get any extra exhaust fumes entering the cabin? I feel like my car is already bad in that dept. Thanks

[agrimmitt]

Mike: How did the car come to you, with the exhaust upgrade or did you add them? Are you looking for the best performance out of you 2.0 or wanted the looks of the dual exit RSR exhaust? Many a pelican has an exhaust system for the street, track, autocross or long trips with the wife!. Most are simple on and off affairs with little time under the car (at least in the early 2.0 cars). You can find a stock muffler and have it "adjusted" for a somewhat stock look, better flow and still have some back pressure. Spent some time around some of the fellow owners in you area (PCA or POC) and see what those guys are running. But what you have now is about as loud as you will be without a open exhaust or "adjusted" stock without anything in it. O'Ya check with you dentist about old fillings falling out. (personally>loud is good)
Cheers
art

[Dan Morton]

Nice looking car. Please post more pics!

I also have the sport muffler on my '68 which was built from a stock muffler and I love the sound especially since I have a 2.6l engine and rain hats over the carbs which help let the sound out Do you have an engine sound mat in the engine compartment? If not, this will probably help some as well.

I would think the stock muffler would be a great option for you. I would be happy to buy your sport muffler if you ever decide to sell I have a stock muffler on my '70 and it's definitely quieter.

I'm assuming you're running weber carbs too. Which air cleaner setup do you have?

[stuntmanmike]

To answer the questions - This exhaust was on the car was when I picked up last week. I like the dual pipe look, especially as the stock opening in the valence? panel has been welded shut. But would hate to be losing power as a result of a "performance" exhaust, and seems sounds like the stock style muffler is the best deal.

There is a sound mat in place. Yes, I have webers, not sure of the differences in air cleaner setups, so here is a photo:

new stuff :: 94160a15.jpg picture by rustyvegas - Photobucket

I'm thinking about trying to cap one of the pipes or trying some baffles per gumba's suggestion...

[agrimmitt]

Originally Posted by stuntmanmike

To answer the questions - This exhaust was on the car was when I picked up last week. I like the dual pipe look, especially as the stock opening in the valence? panel has been welded shut. But would hate to be losing power as a result of a "performance" exhaust, and seems sounds like the stock style muffler is the best deal.

There is a sound mat in place. Yes, I have webers, not sure of the differences in air cleaner setups, so here is a photo:

new stuff :: 94160a15.jpg picture by rustyvegas - Photobucket

I'm thinking about trying to cap one of the pipes or trying some baffles per gumba's suggestion...

Those are aftermarket air cleanes>good one's that do help to increase air flow (thus HP), but the sound level is higher than stock. Seems like you purchased a nice car, did you have the engine checked out by some first? All the things you have shown are period correct upgrades done to a early 2.0 911's to increase torque and hp. Do you have stock Webbers on it (40's) or has the motor be apart>if so I'm thinking you will find "other" upgrades.
Very nice car!
art

[mb911]

careful capping a tail pipe not sure how that muffler is designed some can be capped some can not. good luck shopping

[stuntmanmike]

Hey Art, thanks. I have no idea which webers are on it but will take a closer look...does say made in italy if that means anything. This all happened very fast, I saw the car locally and it was in my possession next day. I had a budget that this fit in and there was a lot of other interest so went for it without a pro PPI...a risk I was willing to take as the motor and trans were redone in 07 by Formula Motorsports in Queens NY. Seems to have some nice power for a 2.0 motor!

[Macroni]

Great community of early car guys in your area. They love to get together and drive. I would post a hello on the early S registry. I have a sports muffler on my 69S. You grow to love the roar when driven aggressively.

[ttweed]

Originally Posted by stuntmanmike

Hey, the exit pipe cut/modification seems to be a good route. Do you get any extra exhaust fumes entering the cabin? I feel like my car is already bad in that dept.

No, I haven't perceived any increase in fumes from pointing the exit down rather than back. If you have strong exhaust fumes in the cabin, it is probably due to the heat exchangers. As they age, you can get some crossover between the exhaust and the heating system airflow. You might check their condition. Many have been replaced with SSI (stainless steel) units over the years as the original mild steel ones deteriorated. I am running straight headers (no heat) in Lo Cal.

I had already notched the valence for the custom twin pipe muffler before painting, and did not want to cut a new side exit and have to touch up the paint. Besides that, when I retire the car from autocross, I plan to reinstall the twin-pipe sport muffler, much to the disappointment of my neighbors, undoubtedly, because I like the sound, and "Loud Pipes Save Lives!"



TT

[m1franck]

Here are my trials and tribulations with mufflers in my '71 911T 2.2l :

Triad-West 2 in - 2 out. This was on my car when I bought it. Nice sound a tad loud and the wife hated it. No drone, unlike other 2 in - 2 out mufflers. Here's a sound clip before it was removed, along with the the 2.2 engine.

IMG_0045.MOV - YouTube

M&K Sport 2 in - 2 out. Very well built muffler. Looked fantastic on the car. Mind numbing drone. Much louder than the Triad West. The wife refused to get in the car. Drove the car 1 hour with this muffler and reinstalled the Triad. The car actually felt slower when compared to the Triad-West muffler.

Dansk Sport. 2 in - 1 out. I prefer the stock, more of a sleeper look to this muffler. Larger diameter tail pipe. Highly recommended by the Porsche experts in the Portland area. Looking forward to hearing it when the new 2.7 goes back into the car. Hopefully the wife will approve

[mb911]

Originally Posted by m1franck

Here are my trials and tribulations with mufflers in my '71 911T 2.2l :

Triad-West 2 in - 2 out. This was on my car when I bought it. Nice sound a tad loud and the wife hated it. No drone, unlike other 2 in - 2 out mufflers. Here's a sound clip before it was removed, along with the the 2.2 engine.

IMG_0045.MOV - YouTube

M&K Sport 2 in - 2 out. Very well built muffler. Looked fantastic on the car. Mind numbing drone. Much louder than the Triad West. The wife refused to get in the car. Drove the car 1 hour with this muffler and reinstalled the Triad. The car actually felt slower when compared to the Triad-West muffler.

Dansk Sport. 2 in - 1 out. I prefer the stock, more of a sleeper look to this muffler. Larger diameter tail pipe. Highly recommended by the Porsche experts in the Portland area. Looking forward to hearing it when the new 2.7 goes back into the car. Hopefully the wife will approve

I have heard those coments on our sports before and have now suggested the tail pipes be upgraded to 2.5" so that there can be a removeable cap sent with so they can switch back and forth good input thanks