if an exhaust fits a 75 wont it fit a 76?

[mrrolleyes]

so i have a 76 2.7

i like this exhaust from sierra but it says up to 75 and when i called they said only up to 75..

http://www.*********************.com/911-930-74-89-/Heat-A-C-and-Exhaust/911-74-89-Heat-and-Exhaust/Dansk-Sport-Muffler-Dual-Outlet-911-63-75-p31948.html

otherwise i would need to acquire one with longer tips and have them cut down..

are the mounting brackets different?


2nd note.

on a 57 vs 50mm dual outlet will it really effect anything like back pressure?

[75 911s]

I think they are accounting for the EGR bung, which midyear mufflers have. There's a bung that leads to the EGR filter, then to the EGR valve and back into the throttle body.

So the Dansk sport 2 in will bolt up, assuming you have the old thermal reactor midyear heat exchangers with the thermals having been replaced with a 3 into one header. and you would just cap off the bung, assuming you don't have to pass emissions visual or otherwise.

Throw a pic up on here. Is the EGR filter still there?

Depending on where your car was destined when new, may answer your question. I think Euro exhausts were different.

Also some later midyears have a different HE setup where all the exhaust gets routed into a single inlet into the muffler. So if you have that setup, you would need to buy SSI to 'backdate' your exhaust to a 74 style setup.

[mrrolleyes]

im on ssi's no egr that i recall.

[75 911s]

then you are totally fine. Direct bolt up. Get new gaskets and new hardware. The copper nuts are handy, if you need to pop the muffler off later. And copper antiseize. The old muffler bolts will be trash, unless they put new ones on when they put the SSI on.



Backpressure seems to be a bit of a black art. Most will tell you Porsche knew what they were doing, but I don't buy into that (in regard to our midyears) because ultimately they had to account for emissions which threw a giant spanner in the works. In my personal experience free flowing muffler is more power. That's why you see straight pass through on rally cars. Search some of Bill V's posts. I think he has a graph showing various mufflers/straight pipes on engines and performance gains.

[mrrolleyes]

Originally Posted by 75 911s

then you are totally fine. Direct bolt up. Get new gaskets and new hardware. The copper nuts are handy. And copper antiseize. The old muffler bolts will be trash, unless they put new ones on when they put the SSI on.

yes all bolts and gaskets are new. i couldnt imagine why it wouldnt fit

[mrrolleyes]

[IMG]http://www.*********************.com/images/products/190086.png[/IMG]

[mrrolleyes]

[IMG]https://www.*****************/uploads/images/product/Silencers_Mufflers/1620610700lr.jpg[/IMG]

[mrrolleyes]

it wont let me link any photos

https://www.google.com/search?q=92.515DUAL&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiYrpXyt4jbAhWBdt8KHSN-DlAQ_AUIDCgD&biw=2425&bih=1091#imgrc=fCHiGLcV30f3aM: