SSI's onto a '76S step 1

[Jim Sims]

Replacing the convoluted exhaust system on my '76S; thermal reactors were removed and replaced by "headers" sometime in the car's past. I'm in the process of upgrading to SSI's.

Step one: removing the EGR filter, heater boxes, "headers", air injection line and air injectors.


Here's what the system looked like at the beginning of the upgrade; note I have been soaking the nuts with "Aero Kroil" aerosol penetrating oil. There is also the good fortune that the PO, when overhauling the engine, re-installed the fasteners with a coating of anti-seize compound on the threads. Note the EGR line from the muffler and the EGR filter (both to be removed).





An image of the driver's side before starting.

[img]



The passenger's side heater box off.





The torque wrench was set at 15 ft-lbs and the header nuts were loosened; all but one loosened at or below this torque value. Image of passenger side with "header" removed. Note the reduced cross-section of the exhaust studs; this feature makes these studs relatively fragile and usually requires heating the nuts to a "cherry red" so they may be removed without breaking off the studs. The use of anti-seize compound on the threads by the PO and soaking the nuts with penetrating oil made nut removal easy in this case.





Next the air injection line was removed; again the PO had coated the threads with anti-seize compound making this task relatively easy. The six nuts attaching the line (it's a single piece unit) to the air injectors were loosened with open end wrenches. One wrench was placed on the air injector hex flats to react the loosening torque. Image of passenger's side with air injection line removed; one can see the three air injectors.




Image of the driver's side with the air injection line removed; note the stud that backed out of the number two cylinder head. No damage occurred to the thread in the head and the nut was removed from the stud later (with the stud secured in a vise on the work bench).





Finally the air injectors were removed; a deep socket was used to loosen them. Here is an image of the passenger side with the air injectors removed.



More later. Jim

[vash]

wow, jim! prepare for me to come over there to "kidnap" you! that is good work. nothing broke on you.

cliff

thanks for the post...

[Bigtoe]

Jim

Great Pics!!!

She's breathing easier now.

2.7 owners UNITE! With great posts like this, we shall ovrcome the "stigma"!!!!!

[CHILI]

Jim,

I just did all of this two days ago! SSI's on my 77 motor. I too, had the "headers" and air injection. Although, my air injection didn't go to anything. It just came up through the shroud and I had a plug, since my car is a 74 and no need for the smog pump, so there was none. I just have bare studs where the pump is supposed to be.

Anyway, if you don't have to smog it anylonger (not sure about MN laws) you can get "air injection delete plugs" and remove the entire set up. They go in the holes at the ports. Much cleaner look. But, with 2300 posts, you probably knew that.

No broken studs for me, either. I've had my exaust off twice now with no problems.

[jase007]

I too will be performing this surgery soon on my '76S Targa.

Looks good.

Jason

[azasadny]

Jim,
Thanks for documenting the process, it will help when I get the nerve (and cash) to switch my car to SSI's!!

[Bill Douglas]

The engine is nice and clean looking, without oil, grease and rust - it must be a good one

[911mike]

Did the '76 come with EGR valve? Last time I smogged the car the technician said it was only '77 and newer.

[vash]

i have two columns in my 911 binder. the first column is titled "stuff i have to do" and #2 is "upgrades" #1 is stuff to get the car moving and stopping safely. #2 is self explanatory. the problem comes up when things conflict. i need to change my oil return tubes, and install tensioners. if i need to drop my exhaust, this would be the best damn time to put up some new SSI's and muffler. bummer i already commited to installing MARVIN dual paned windows (DIY). i would be blending the two columns right now. jim is hooking me up with some of the airline plugs. that air pump is in the way of my new tensioners, no way i am putting it back in.

cliff

[Jim Sims]

Engine was out in 2002 for cleaning and some resealing; present oil is mainly due to a spill (funnel to oil tank tilted over during an oil change). Car was first sold in California and the '76 models were equipped with thermal reactors, air pump and injection system and EGR system; 74-77 factory parts catalog shows these systems for the California bound cars. Cheers, Jim

[MAS]

Any idea how much of a HP/performance gain you get from doing this?


-MAS

[Jim Sims]

At my altitude (7000ft or 2140m) probably 8 to 10 hp; at SL 10 to 12 hp. Jim

[deanp]

Jim - You have a PM.

[AlexGross]

Great thread! Im in the process of swapping out the stock HEs on my '75S, and I've been trying to figure out how to get rid of the ugly and unused air injection system. Thanks to you I've got an idea of how to do it now ...guess I know what my plans are this weekend. I think this will really clean up the undercarriage, I really didn't want to slap all that ugly piping back on top of new oil return lines, cleaned cylinders and heads, and shiny new headers. This is my first porsche and first rebuild; I am really enjoying the slippery slope that my top end refresh has turned into.

I've got a thread following my project and always appreciate advice/suggestions:

Reviving Grandpa's '75 911S

[Milo2361]

glad to see i wasn't the only one to get the SSI job going without snapping any studs! you'll love the SSIs - wakes the car up immensely(at least it did on mine, got rid of the crossover and Cat), not to mention the sound is sooo much better.