On an early 911, do SSI heat exchangers change the amount / character of the exhaust noise? Thinking particularly of noise at about 75MPH, the speed limit here in S.A. Also, does the ANSA muffler have the same sound as the OEM item?

Ideal solution is nice noises while accelerating, quit while cruising...

BTW, the car already has SSIs, my question is directed more towards finding out how much of the present noise can be avoided.

TIA

Mark

 

Mark,

The earlier 911 heat exchanger's had the same basic shape as the SSI's, just not in stainless steel. However, the primary toning of the exhaust is done via the muffler. I have a modified ANSA on my '81SC and the sound is OK, and it could be louder without annoying people. You really need to attend a Porsche driving event or club event to listen to what various owners have installed. They are all a bit different. Plus you need to consider if you need warranty repair, can it be done in your home country (more important on stainless steel mufflers that should last a long time).

 

This question followed a Sunday outing with the club - did about 200 miles, and the 75MPH drone was a bit tiring, and this set me thinking. When I last drove it, the '69 (with stock heat exchangers and muffler) was a good bit quieter than the '70. Admittedly the muffler is in better shape on the '69, but after putting the SSIs on the '70 its engine note seemed to be quite metallic.

Unless there is a good vote in favour of a stock/ANSA muffler, I'll try to get one made up locally. I know, the ultimate solution is to drive faster than the noise...

 

Some people think this is absurd but i had a muffler system made for my 72. A little louder than stock at idle and cruising. But, the tone when i get on the gas is like no other porsche i have heard. Had to mess w\the mfi to get it right.I noticed more low end, a little flat spot from 2200 to 2700 then it screams up to 6000. Not much after that with e cams. This is on a 72.