1925cc converston

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Winston Teague
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1925cc converston

Post by Winston Teague »

Hi 356 gurus....
viewtopic.php?t=70671

This describes a 1925cc upgrade. Achieved with std S90 crank....this sounds very interesting as presumably the increase is all/only in the barrels and pistons....does anyone know more about this?

W
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Re: 1925cc converston

Post by newto912 »

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Re: 1925cc converston

Post by Winston Teague »

Ah, that interesting. Has anyone done a DIY install of any of this stuff? I like the idea of an engine that is just like the one I have , but a third bigger, just increasing the capacity would raise the compression ratio, and should be a punchier version of standard.....
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Re: 1925cc converston

Post by hot66 »

Same principle as basic VW tuning. I do know there is a point on the vw side of things that with slip in barrels you could get to the point where then cylinder wall was getting quite thin which upset cooling . Better to machine heads and cases for thicker wall cylinders. This was only if you pushed the capacity increase too far using a stock throw crank
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Re: 1925cc converston

Post by newto912 »

I thought about this for a while for a 912 engine I plan on rebuilding. I am pretty sure , if you look on the Willhoit website he goes though the steps needed to add his kit to a standard case, I do recall machine work to the case will be required.
Perhaps you could ask whoever did the work on the 356 that is for sale, and the cost!
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Re: 1925cc converston

Post by newto912 »

Sorry , machine work for the 2.2 kit, not the 1925s
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Re: 1925cc converston

Post by hashman »

I think you need machine work to the case halves and heads for any thing over 1720. Even the 1883 kit requires it.
Its one of the reasons Ive decided on 1720 for my current rebuild, I can always return to original 1600.
Unless I come into a large amount of money those larger capacity kits will remain a dream.

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Re: 1925cc converston

Post by Winston Teague »

All the above is interesting, coupled with my unexplored curiosity over the 2.1WBX camper engine out in the shed.....is the centre distance between the cam and the crank different to the 356? W
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Re: 1925cc converston

Post by Bruce M »

WBX is very similar dimensions to the VW type1 engine. Same cam bearings & spacing to crank. The crank is similar to type1 except it is more beefy to prevent flex and the flywheel spigot is the type4 version with 5 small bolts instead of the big single 36mm bolt. The 1.9l has 69mm stroke (same as 13/1600 type1) but the 2.1 uses a longer stroke crank.
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Re: 1925cc converston

Post by Winston Teague »

So, how closely does the 356 bottom end follow this? Can WBX innards fit a 356 case? W
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Re: 1925cc converston

Post by misteralz »

Now that could be a properly interesting engine. I know there were a few 'oxyboxer' engines built by combining type 1 and WBX bits. Gonna have to go and look that up now...
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Re: 1925cc converston

Post by Bruce M »

Winston Teague wrote:So, how closely does the 356 bottom end follow this? Can WBX innards fit a 356 case? W
Not without significant machining, I’d imagine. You can fit a WBX crank in a type1 but the flywheel bearing has a bigger OD and the case needs machining to open up the bearing saddle for the bigger OD. Also, need a type4 200mm flywheel, which might be a problem for the 356 clutch/bellhousing/starter.
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Re: 1925cc converston

Post by Winston Teague »

Interesting stuff. Making a bespoke flywheel is pretty straight forward. What do you mean by 'flywheel bearing'? W
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Re: 1925cc converston

Post by KS »

I think Bruce means the bearing in the flywheel which supports the gearbox input shaft.
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Re: 1925cc converston

Post by Winston Teague »

Ah, OK, well that would be a simple tweak in the design of the bespoke flywheel. So I assume the other thing is machining (line boring) the case for a bigger main bearing diameter.....W
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