69mm crank type 4 main jounals

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Would it be worth a 69.5mm crank with type 4 main bearings ..what do guys think .....

[Dan Ruddock]

Yes, it would be a good idea if your engine was a 12,000-rpm engine. Seriously there is no need for that in a 69mm crank. T4 mains are added to recover the cranks strength lost when adding more stroke to a crank.

[Dauz]

Depends on what you're doing with it. But 411 center should more than suffice

[Pruneman99]

I wouldn't bother unless I happened to find the parts already modified for sale cheap or something.

[Dauz]

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[Pruneman99]

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[Pruneman99]

Geez. You're missing the point.

Dpr center main conversion $115.00
Center bearing $50.00 or same price for the conversion bearing if you can find one in stock.
You'd need the case cut for a standard type 4 bearing. $50.00?
SHIPPING your crank and case both ways $100.00

So $250.00 - $300.00. Extra. For a regular ol 1600, its not worth it. 1600 racing engine, that's a different story. Or, if you happened to find the parts cheap.

If you live in Santa Ana, you can drop your stuff yourself. Most people do not live in Santa Ana.

[raymon covey]

If it was not better why would vw use the larger type main on the 1700 cc motor with a 66 stroke and the same on the 2 litre with the 72 stroke. The center main on the type one it the one that wears first. Two rods oil from this main. I think this would be a definite improvement if you are going to purchase a new crank.

[Vanapplebomb]

Just because the three large mains on a T4 didn’t always mean things worked better. The 66mm stroke crank was a beast, and by far my favorite T4 crank. The 71mm crank… not so much. I don’t like the 71mm 2.0 cranks because they flex like a bug crank at high rpm. In 1972 when they started 2.0 production, they used the existing forging for the 66mm crank, and offset ground the rod journals 2.5mm, and ground them 5mm smaller in diameter to get the longer stroke. Great thinking from a manufacturing standpoint, but weaker like a bug crank… and the large mains didn’t fix that issue.

But in general, I think you are correct. The T4 was introduced at a time when VW was trying to make an engine more competitive with water cooled vehicles of the day. Everything was built heavier and bigger in those engines… until ‘72 when the 2.0 started production. Despite being the most powerful (95-105hp), they went backwards in my opinion.
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1800 Type 4 Berrien 295

http://www.thesamba.com/vw/forum/viewtopic.php?t=487021

[Pruneman99]

Nobody is arguing if it's better or not.

[RCP Phx]

Diameter bad, width good!

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Jose has video on his dpr facebook of him working on a destroke 50.5mm crankshaft ..I also remember hearing that ..that crank also may of had type 4 mains ... I wonder what that crank / engine was build for ....

[Pruneman99]

50.5 mm VW crank? That would be interesting. I've thought of that before if you wanted a high rpm formula racing engine. You'd need to have pretty good valve control, then zip around the track turning 8-10k rpms lol.

I bet it would sound insane.

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