Porsche Repair: 1976 911S, solex carbs, porsche 911s


Question
I recently got a Porsche 911S. The problem is that the fuel injection on it is basically shot. I'm thinking of converting it to a carbeurated engine using the Solex carbs. How much pain am I asking for by trying this? Also do you happen to know the correct timing for this car? I've hit a thousand people with this question and gotten everything from 5 degrees ATDC to 20 degrees BTDC. I live in Japan and finding manuals of any kind for this car is near impossible so I don't know. Any help you can offer is greatly appreciated.

Steve

Answer
Steve, I'd think long and hard about the carb swap.  I can see how it would look tempting, I'd consider it too.  The question of 'pain' is so subjective...I assume you're thinking of the bad kind of pain...like a pain in the neck, a pain in the pocketbook, and a pain in your stress level.  There is good pain too...it comes from working on a project where it's long and involved, but worth every moment because of the self-satisfaction it reaps.

On the one hand this swap should be easy, since there are still 911's with Solex's and the right induction housings running around.  On the other hand you'll have to work out the details of jet sizes, carb synchonization, and timing.  The same could be said about the injection set-up...it should be easy to get replacement parts, but you'll have to have a different mind-set...and let the computer do all the tuning work for you.  

I used to think that carbs=good and fuel injection=bad...until I drove an injected car every day.  I've changed my mind, realizing they can both be good...or bad, depending on the car, what you want to do with the car, how much time you want to devote to tuning and tweaking, etc.

As for ignition timing, I suspect the wide range of numbers accounts for those people who set their timing statically vs. dynamically.  This is not the "official" word, but the best numbers I could find were 5 degrees ATDC statically (engine off or idling at about 800-900) and 32-38 degrees  dynamically (as high as she'll rev safely, with full advance).

I buy all my reference materials online and have them shipped to my door.  You could do the same, can't you?  My recommended manual is published by Haynes, and is called Porsche 911, Automotive Repair Manual.  I know they cover '76 in this soft covered manual...it's normally just shy of $20.

Good luck with the 'S'.  The lines on the body during that era was always one of my favorites.  

Dave