Big Bore kit for Super 90

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Harlan Halsey
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Re: Big Bore kit for Super 90

#31 Post by Harlan Halsey »

Yes,
It was that way for a lot of people. The long time second owner of the 63SC which I bought in 1977 warned me that parts were impossible to get and that was why they were selling the car. I've been enjoying it ever since. For a long time, I just maintained and drove it, Then at 135,000 I took the engine apart, found everything OK and reassembled it with new bearings and rings. Then about ten years ago I had Bruce fix the dents, repaint it and put in a new AUTOS interior. I hot rodded it by painting the garnish rails and leaving the vinyl covering off a' la'' an A. In a few days it will turn 200,000 miles and become a low mileage matching numbers car again. I didn't tell the second owner that I knew I could get the parts.

Edwin Ek
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Re: Big Bore kit for Super 90

#32 Post by Edwin Ek »

Don't you wish you had installed a full-flow filter so that you could have gotten decent engine life? :)
#6386

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Harlan Halsey
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Re: Big Bore kit for Super 90

#33 Post by Harlan Halsey »

LOL

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Dennis Vogel
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Re: Big Bore kit for Super 90

#34 Post by Dennis Vogel »

Nate Greene wrote: Tue Jun 11, 2019 2:37 pm I know this has been asked many times, but I am about to purchase new cylinders and pistons for the 1963 356B Super 90. I do not race or hot rod but I like reliability if I want to drive to a 356 Holiday, etc. This Forum is the best source for information.

Anybody have a strong recommendation for a Big Bore kit?
We recently went through the same dilema rebuiling our S90 engine. Ultimately ended up buying the AA kit. Some background on the thinking is documented on my blog.
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S

Mike Horton
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Re: Big Bore kit for Super 90

#35 Post by Mike Horton »

I have recently bought the AA 86mm big bore 22* head angle set, inspected them very closely, for clearances, weight balance, ec., bought directly from AA, and these sets have such demand from this 356 community, when I finally caught them in stock at AA, I looked no further. I installed these in my '62 S90 engine, and am on the threshold of running it. I was impressed with the hypereutectic piston's CNC machining quality, coated skirts, plated piston tops, which were fully machined, unlike my Japanese set was, and because these S90 heads had such good integrity, this match enabled me to move forward with my build. I set the C/R, at just under the factory stock 9:1 in deference to the road fuels we have available these days. I used an excellent condition narrow lobe stock 102 cam, and spherical radiused tappets, from Jacques. Unlike the earlier AA 30* sets I'd seen this late set came with unpainted cast iron cylinder exterior surfaces, which I coated black, just my preference, I'm picky, and have my reasons. I have no issues with the JE forged pistons, other than the piston slap, of their centered pin location, like my 1st '57 A T1. This is a spare engine for me, and I no longer compete, so for a cruiser engine, i'm happy. In my aviation days, I saw both cast, and forged pistons fail, but I always found the root cause elsewhere. For clearance specs, I compared these AA parts to the original 356C set, the parts from which all the clones, were copied, just my choice, and opinion.

Dan, you were able to get the 22* angle set from AA? Good to know,

Oh, yes, I after 55 years with these engines, I too, like those in the blog above, much prefer the cast iron cylinders, to other more costly options, due to their performance, oil control, and regidity, their ability to retain their shape... "round", as well as my experiences.
Mike

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David Craigmyle
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Re: Big Bore kit for Super 90

#36 Post by David Craigmyle »

I am rebuilding my 69 912 engine and cannot find any heads that are useable. Mine are shot.
I have a good pair of s90 heads and was planning to use them with the AA big bore set designed for a 22 degree angle. Is there any reason why I should not do this?
Also can I use the 912 rockers, pushrods etc with the S90 heads. We plan to use a new cam, any suggestions on the best one for this set up.
Are there any issues with fitting the 912 tinware if I use S90 heads?

Original 912 crank has been reground to first under.

Here are some pictures of the heads for information.

https://photos.app.goo.gl/Hr5rKP6BU1vkvJRV6

I am a novice so keep any advice simple!

Mike Horton
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Re: Big Bore kit for Super 90

#37 Post by Mike Horton »

David Jones wrote: Wed Jun 12, 2019 2:33 pm I have bought a lot of stuff from from CIP1 over the years and it has been worth what I paid. I question these however as to what set it is 30 or 22 degrees and they got the capacity wrong. How can they make 86mm into 1775cc?
... old Performance Products marketing, perpetuated still...
Mike

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Re: Big Bore kit for Super 90

#38 Post by Mike Horton »

"Also can I use the 912 rockers, push rods etc with the S90 heads. We plan to use a new cam, any suggestions on the best one for this set up.
Are there any issues with fitting the 912 tinware if I use S90 heads?"

Yes, as long as the rocker stands are the later aluminum version, rather than the early magnesium,

"We plan to use a new cam, any suggestions on the best one for this set up."

There is a world of information on cams, and their use, and like "which oil?", or "what C/R?", previously spoken to on this forum, and can be easily found by a search, I'll not go there. For my cruiser, and daily type use, I chose to stay with the stock S, SC, & early 912 cam,

"Are there any issues with fitting the 912 tinware if I use S90 heads?"

Only in your decision on whether to use the right side breather connection to the oil tower, or not, as in the "C" engines, which only use the top one, routed to the passenger's air filter, for the "suction through that carb.", to make the closed breather system work.
Mike

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Nate Greene
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Re: Big Bore kit for Super 90

#39 Post by Nate Greene »

Bought the AA set and now have 200 miles on the rebuild. All good so far.
Nate J. Greene
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1963 356B Super 90
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Paul Lima
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Re: Big Bore kit for Super 90

#40 Post by Paul Lima »

Another vote for Shasta. Leonard knows his stuff and can get you exactly what you need. I just finished an engine with Shasta Design (90 mm) pistons and cylinders, with his Neutek SX-2 camshaft. Could not be happier.

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Al Zim
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Re: Big Bore kit for Super 90

#41 Post by Al Zim »

I highly regard Mike Horton ability to assemble air cooled engines. Primarily he did this for aircraft which precludes stopping by the side of the road to fix a situation. However, one of the reasons for my concern with cylinders with larger bores is that the sealing surface between the head and the cylinder is substantially reduced. If the head is not machined properly a compression leak will occur. While I may seem like a heretic the 1500 CC engine with a 80MM bore gives substantially better sealing. Almost ll my life I have owned a Normal, except for the speed of acceleration I have found these engines to be much easier to drive. Smooth on take off (heavy flywheel) and excellent gas mileage. Would I drive on on the Texas Freeways west of FT. Worth? Not on you life when the speed limit is 85. Not once have I ever seen discussion about properly finishing rocker arm tips. Just an observation al zim
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