Rebuild 356 normal engine

[Ron LaDow]

Jacques and David,
I'm in your camp; a new crank is preferable everywhere and always. But given the low RPM loads here, if there ever was a candidate for reuse, this would be it.
Assuming it passes the measuring tests, and given that mileage in an unfiltered engine, I doubt it.
But Jacques: "question are you better off getting a new crank or investing in a fullflow filter after the harm/fatigue had been done?"
I don't understand the question. It sounds like you see this as an either/or, but I don't see it that way.
(but cya Saturday!)

[fred bronson]

Thanks to everyone for the information. I have a lot to learn but looking forward to a new project.

[Tom Wavrin]

Fred, contact me if you would like to borrow my Maestro's guide to rebuilding an engine. I had my heads rebuilt by Walt's Competition Engineering. The cam and followers were redone by Dema Elgin. ***I believe you can now buy P/C sets that have the original contact angle that matches your heads so no material will need to be removed from them.*** I highly recommend Doug Fenstamel at type356a.com for fuel pump parts or rebuild and Ab Tiedemann for the distributor. I leaned heavily on the generous expertise of this forum and a local mentor to complete my engine and I am very happy with the end result. Tom, S. OR

[Steve Hatfield]

I love this topic.
On cranks:
I’ve heard this ‘crank life’ argument/discussion many times over and over again. Here’s my input.
I have a guy that many of you may know outside Dallas who I send all my cranks to once they pass the gong/visual test.
He cleans then mags then pulls plugs then measures and cuts but never over 2nd, balances and then sends it off to a re-nitrider, a process which he claims adds both surface to about 2 thou deep and adds about a thou. dem.
He claims that cranks that have gone through this process are completely revitalized and are as good as factory New. All for 7-800.

Comments?

[John Brooks]

Tom

Fred lives a couple miles south of me. I have all of Harry's books and videos, all the P Tools, and stands here on the island, and I am helping Tom Olsen do his engine right now and Fred is also helping.

Tom has a "Maestro" engine right down to the "signature 6-8 big screwdriver strikes" on the crank cam drive gear. Its getting all new internal moving parts, should be a very nice engine when we are done.

[Jim Liberty]

My partner Chuck Young is the motor builder at our shop. We both feel the labor is the key to a successful build. And, we always buy the very best components no matter the cost. When in doubt, replace, do it once, do it right.

.............................Jim.

[Doug McDonnell]

Devil’s advocate here. It sounds like you engine is still fine. Just adding a big bore kit will not change your power more than maybe 4%. If that will make you happy then by all means rebuild your engine. If you really want more power then build or buy an Sc or 912 motor and mothball your numbers matching Normal.

[Dan Epperly]

I love this topic.
On cranks:
I’ve heard this ‘crank life’ argument/discussion many times over and over again. Here’s my input.
I have a guy that many of you may know outside Dallas who I send all my cranks to once they pass the gong/visual test.
He cleans then mags then pulls plugs then measures and cuts but never over 2nd, balances and then sends it off to a re-nitrider, a process which he claims adds both surface to about 2 thou deep and adds about a thou. dem.
He claims that cranks that have gone through this process are completely revitalized and are as good as factory New. All for 7-800.

Comments?

For a couple hundred more you can get a new AA crank.
Of course your bearing costs are going to be more if you are going from a Normal or S and the case will have to be machined for tabs I believe in some cases. But still, even with that added costs I'd take a new crank.

[Al Zim]

Get a professional engine builder with a excellent reputation to build your engine. There is just too much that you do not know! do you have a dial bore gauge to measure the difference between the size of the big end of the rod and size of the crank so you get the proper crank to rod clearance or are you going to bet your overhaul on a piece of plastigauge? What are you going to do about the rocker tips? I have watched many videos about engine rebuilding most of the turn a worn out engine into a piece of scrap iron. Your best bet to reconfigure your engine to super configuration You will need super pistons and super venturi and jets for your carburetor. Because of poor quality control of the piston cylinder clearance and the reduced cylinder to head sealing surface I would not recommend this choice. al zim doing Porsche's since 1961.

[Martin Benade]

Steve, I think what your guy does makes a crank completely revitalized on the outer surface only, to .002 deep. All the deeper parts of it still have been flexed many cycles, leaving it ready to crack sometime in the next 100 years if it feels like it.

[Harlan Halsey]

To answer your question, no. Those compression numbers do not justify a rebuild.

More power is another question, the answer to which is why? Street? Race? Get up a local hill faster? Be able to pass where you can't now? In any event more power will be costly. Cubic $$.

I have driven my Porsches about as far as you have and I am particularly skeptical about the big bore P/C and the "full flow" oil systems which seem to get mentioned frequently.

Fortunately for you there are several 356 knowledgeable people near you with whom you can consult.

[Martin Benade]

Big bore P/C is almost the standard way to go nowadays, with good quality parts there is no problem at all. And how could one question the benefit of filtering ALL the oil all the time instead of only 7%? I have never heard of a benefit from running dirty oil.

[Rudy Bernhard]

Fred,
Congrats on all of that enjoyable 356 driving! Chances are your current annual mileage added to your 'still runs fine' car is about 1000 miles per year, if you are like most with a second car. Over the next 10 years, you will not accumulate significant mileage, or greatly increase your chance of needing a major rebuild. If it ain't broke, don't fix it. It fits you like a glove, and you are not racing it. There is down time to fix anything on a car. I just went through too much time without driving my coupe to 'improve' it. Drive it. Enjoy the comments you get when you fill it up. Wave at the people who give you the thumbs up. And I understand you are helping perform a friend's rebuild now. Enjoy the experience, then enjoy your drive home in your still running car while he wishes he was driving his.

Rudy
Don't spend so much time with your car out of service chasing perfection, that you have no time to drive your 356! Drive 'em!

[Harlan Halsey]

[quote="Martin Benade"]Big bore P/C is almost the standard way to go nowadays, with good quality parts there is no problem at all.

I remember when the NPR "big bore" P/C first became available. At that time the Mahle P/C had become so expensive that they cost more than the rest of the rebuild. The NPRs cost about 1/4 of the Porsche cost. People bought them because they were a whole lot cheaper, and they worked on the street. The 356 Porsche was a special car. Besides the high build quality, there was a wide range of transmission gears available, and the engine displacements were always at the racing class limit, 1500 then 1600 cc. I think you are correct that today "big bore" is a very common choice and that it is viewed as cheap horsepower, by those who care little for the things which made the 356 so unique.

[Harlan Halsey]

And how could one question the benefit of filtering ALL the oil all the time instead of only 7%? I have never heard of a benefit from running dirty oil.

I still have the first Porsche engine that I purchased in 1964 with 24,000 miles on it. I drove that car, a B coupe, summer and winter daily, and towed my race car with it for four years. When I disassembled the engine at 96,000 miles, it was clean inside and everything measured to spec, including the crank shaft journals. I reassembled it and have put another 35,000 miles on it since. Note that air-cooled VWs have no oil filter. I concluded long ago that with oil changes every 2,000 miles or so and with a filter change every 10,000 miles, there is no benefit to more oil filtering.

However, were I to conclude that more filtration is desirable, I would not nestle the filter among the exhaust pipes, rather I would do it the way it is done on the 356 race cars. BTW, I do have full flow filtering on my race cars: Carrera, Ginetta G4, and Lotus Elite. That's not to clean the oil, it's to keep broken bits from contaminating the car oil cooler plumbing.