Oil Cap

For those who obsess about exactly how their 356 left the factory!
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Charles H Jacobus
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Oil Cap

#1 Post by Charles H Jacobus »

There are two types of oil caps, one flat (and I've mostly seen silver) and one with a raised center across the cap. Which is the correct cap for a 1965C? Stoddard says the flat one is for a 356 912 99921100400 and the raised center one is for 356B T6, 356C, and 911 912 1965-77, Used as 911 Oil Cap for 1965-1971. 90120127100


Chuck
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Current:
2012 Silver 991
1995 Midnight blue 993
1965 Red 356C

Past:
Fond memories of 14 others (including a '63 Normal and a 61 S90) :)

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Vic Skirmants
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Re: Oil Cap

#2 Post by Vic Skirmants »

Top one is correct. Bottom one is for gas tank, but can be used for the oil can. It fits, but is not original to that location.

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C J Murray
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Re: Oil Cap

#3 Post by C J Murray »

In 1972 maybe the 911 with the oil cap door on the rear fender should have had a more emphatic OEL only warning on its cap.
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Charles H Jacobus
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Re: Oil Cap

#4 Post by Charles H Jacobus »

Thanks, guys!

Vic, I rode in the gray 1960B you sold to Patrick. He has put a Willhoit 2.2 in it! Powerful, but seems to have significant 2nd order vibrations (you can feel the explosions) and it doesn't breath as well as an early 911 above 5500. Do you have experience with these? Did you experience that? Are all large displacement engines like that?

Chuck
Current:
2012 Silver 991
1995 Midnight blue 993
1965 Red 356C

Past:
Fond memories of 14 others (including a '63 Normal and a 61 S90) :)

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Vic Skirmants
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Re: Oil Cap

#5 Post by Vic Skirmants »

Charles H Jacobus wrote: Mon Feb 18, 2019 9:04 am Thanks, guys!

Vic, I rode in the gray 1960B you sold to Patrick. He has put a Willhoit 2.2 in it! Powerful, but seems to have significant 2nd order vibrations (you can feel the explosions) and it doesn't breath as well as an early 911 above 5500. Do you have experience with these? Did you experience that? Are all large displacement engines like that?

Chuck
Don't know which car you are referring to. I don't have any experience with large capacity 356 engines. 1620cc full race or 1720cc street; that's it. Could be a carburetor issue.

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C J Murray
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Re: Oil Cap

#6 Post by C J Murray »

Charles H Jacobus wrote: Mon Feb 18, 2019 9:04 am Thanks, guys!

Vic, I rode in the gray 1960B you sold to Patrick. He has put a Willhoit 2.2 in it! Powerful, but seems to have significant 2nd order vibrations (you can feel the explosions) and it doesn't breath as well as an early 911 above 5500. Do you have experience with these? Did you experience that? Are all large displacement engines like that?

Chuck
I am the person that that came up with the way to get the 82mm stroke and shared that with John Willhoit. I have 25000 miles on my 2133cc with some long distance trips as well as commuting locally. I drove John's prototype car and he drove mine when I was inSoCal with it. Like everything, there is no free lunch. Longer stroke and bigger displacement cylinders cause more vibration. It isn't horrible but it is quite different from a small engine. The torque is the payoff. So much so that I installed a 10% taller r&p for lower rpm. When I got back from CA I had a cam failing and I was not happy with the relatively high oil temps(no front cooler) so I redesigned my configuration with less spring pressure and a less aggressive cam opening and closing and less lift. I also made a change that I don't want to disclose that made a very big difference. On top of that I changed to a 123 Tune Bluetooth distributor with vacuum control. The car is transformed, much better, but it will never be as smooth as a stock C. As for redline, mine pulls very strongly to 6500 rpm and that is higher than I care to run an engine with that much stroke. It is not a fussy runner and you can drive under 3000 rpm all day if you wish. You have to understand performance tuning to make one of those run well. The are set up completely different from the small engines.
'57 Speedster
'59 Sunroof
'60 Devin D Porsche Race Car
'63 Cabriolet "Norm"
'67 911 S Original Owner
'03 Ferrari 575M
'09 Smart Passion

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C J Murray
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Re: Oil Cap

#7 Post by C J Murray »

Dyno data can be misleading but if you concentrate on the shape of the curves you can learn a lot. 2133/1 was my first engine that I was not happy with. That was on an older engine dyno. 2133/2 was the revised version but before I had worked out the tuning and that was done on a modern chassis dyno with approximately a 15% loss to the rear wheels, or about 150 hp at the crank. So the first version made a little more hp than torque and the second version makes a little more torque than hp. Not all that different really. The second version is less rough but that is mostly due to tuning improvements.
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'57 Speedster
'59 Sunroof
'60 Devin D Porsche Race Car
'63 Cabriolet "Norm"
'67 911 S Original Owner
'03 Ferrari 575M
'09 Smart Passion

User avatar
Charles H Jacobus
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Posts: 493
Joined: Wed May 28, 2014 5:02 pm
Location: Dallas, TX

Re: Oil Cap

#8 Post by Charles H Jacobus »

That's wonderful and very impressive CJ! I'm assuming the lower one was with your undisclosed change. I was quite impressed with the 123 (in theory as I don't have one). I can't figure out why there is such a definitive cutoff at 35*. It seems to me it should be a more gentle curve which of course you could possible do with a 123. Do you have a web site?

In all my 911s, I shift at 5,500 as that's quite comfortable. My 356 gets shifted normally about 4,000 just because it doesn't breath as comfortably.

Chuck
BTW I had a '67 911 and thought it was on of the best 911s I had. The '69S I had in Germany was equally as good and it was wonderful cruising at 200Ks.
Congratulations on your Devin and good luck at the track!
Current:
2012 Silver 991
1995 Midnight blue 993
1965 Red 356C

Past:
Fond memories of 14 others (including a '63 Normal and a 61 S90) :)

User avatar
C J Murray
356 Fan
Posts: 9158
Joined: Fri Oct 23, 2009 7:24 pm
Location: 30MI WEST OF PHILA
Contact:

Re: Oil Cap

#9 Post by C J Murray »

Thanks Chuck.

No website, just cobwebs. :D

The lower numbers in 2014 are the later version, rear wheel numbers, around 85% of the crank numbers. 2012 is first version, measured at crank. You can't really compare the two accurately but you can discern a difference. I never got around to a new dyno run after I dialed in the 123 and the jetting.
'57 Speedster
'59 Sunroof
'60 Devin D Porsche Race Car
'63 Cabriolet "Norm"
'67 911 S Original Owner
'03 Ferrari 575M
'09 Smart Passion

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