Fitting SSIs 80' SC 3.0 with Carrera 3.2 heads

[White911SC]

As the title indicates, I am interested in (re) fitting SSIs to an 80' 911 SC with a 3.0 engine and Carrera 3.2 heads.

The car is currently fitted with the original 3.0 small-port heads and the correct SSI heat exchanger set for USA 911SC 3.0 1980-1983 p.n. 91-915SSI. So...f/3.0 heads, 38mm OD, thick-flange, w/O2 bung.

Car also, has required (2) oil lines changed plus backdated 1974 2-in, 1-out Dansk sport muffler. Current exhaust fits/works as expected.

Since the exhaust port/diameter is different between the 3.0 heads and 3.2 heads, the SSIs required for these (2) vehicles have different diameter head pipes which protrude above the (thick) flange and insert into the heads.

In order to accomodate increased engine displacement/head I/O flow I will be using 3.2 Carrera heads and also plan to upgrade to the newer 41mm OD SSI heat exchangers.

Since I need to fit the new exhaust pipes to the 3.2 heads, I was planning to buy 41mm SSI heat exchanger set for USA 911 Carrera 3.2L 1984-1989 p.n. 911 91.917SSI41. So...f/3.2heads, 41mm OD, thick-flange, w/O2 bung, for 2-in muffler.

ASSumptions I'm making...:
1) If used on a Carrera 3.2 car (which is not what I have) I expect either Carrera 38mm or 41mm set to fit the same.

2) Other than the difference in SSI head pipe which inserts into the 3.0 vs 3.2 exhaust port above the (thick) head flange all other installed dimensions are basically the same??

3) With Carrera 3.2 heads on my SC 3.0 the SSIs should be a straight up 1:1 direct fit replacement??


Looking for a sanity check on my assumptions...Anyone out there with a 911 SC swapped heads to 3.2 and actually installed a set Carrerra SSIs (either 38mm or 41mm headpipes)??