The Official 356Talk Forum

My son and I are having our 63 S90 coupe restored with the intent of making it concours, but we have a dilemma concerning the engine. We would really like to get the collective wisdom of the Registry on this one.
Givens:
-KARDEX and CoA information indicate VIN, trans, and engine numbers match.
-Original S90 motor, 0800533, replaced in Jan 1967 by Porsche dealer in Kaiserslautern, GE with SUPER motor, KD P 704648 (replacement motor consistently documented in KARDEX, CoA, and original vehicle maintenance book).
-We came in possession of the car in 1984 after at least three (3) other owners at which point...wait for it...the engine was unidentifiable. A real kluge. To wit, other than the correct case and maybe the fan housing, the engine had Normal heads (1 ea early A/B and late-B), Weber 48s on Weber manifolds, aftermarket air cleaners, and 912 crank, cam, and flywheel (180). Engine electrics are all date coded btwn 1966 and 1969.
-We have a period correct S90 replacement motor.

For the purpose of making the car concours do we:
Option 1: Use period correct S90 motor for factory "incorrect" replacement motor.
Option 2: Rebuild the original Super replacement motor to specs.
Option 3: Rebuild Super replacement motor as S90 from the case out?
Thanks a million and we look forward to your thoughts, suggestions and comments!
Al and Mario Manzo

The Super engine may have more of its parts than you think. The heads are the same for N and S, only the S90 had larger ports, and the if the clutch is a 180 mm that sounds correct. I also think the early and late B heads are essentially the same. As for concours, its pretty much a toss-up which way to go. If you are selling it, different customers will disagree as to which way is more desirable. It will not be the most true version of "numbers matching" ever again unless you can find that original S-90. In concours judging do they ever check the Kardex?

A heads have shallower valve spring pockets and brass intake seats. Early B heads have deeper pockets and brass intake seats. Late B heads have deep pockets and steel seats.
I would go with S-90 build. Unless the Kardex is consulted, it will look correct.

Thank you Martin and Vic! Appreciate your feedback. This is good news as we were beginning to rebuild the S90 but then started to second-guess ourselves. We bought the S90 motor with the intent of using it in the car and putting the Super on the shelf, but including it with the rest of the car when it was sold.

4 YEARS after the car was built, a DEALER replaced the engine with a different-spec motor. For whatever reason, that swap was recorded on the Kardex.

Go back to S90 configuration.

Thanks Edwin! Really appreciate the inputs from those of you that have been doing this longer than we have.