The simple answer to this question is yes, AND no.

  The piston cylinders are the same. The bore for both engines is 94mm. Most of the differences lie in the reciprocating assemblies. The crank has a greater stroke in the 2.1, which means the rods and pistons need to be different to deal with those mechanical differences. The crank from a 1.9 will fit in a 2.1 case, but a 2.1 crank will NOT fit in a 1.9 case. When new cases were available from VW, they specified that 2.1 cases were all there would be, and that was O.K. Rods are not interchangable. Pistons are not interchangable. I believe the rings are, however.

  So, a possible set-up could be to take ALL the innards from a 1.9, and put them in a 2.1 case. This assumes there are no issues with the 2.1 case to start with.

  And don't forget about the cam, either. The journals are exactly the same, but the grinds are slightly different, so using a 2.1 cam in a 1.9 is a slight "hotrod" - but not much. Any Type 1 cam for a 1600 based case is also usable. Just so the cam gear is the correct type to match what is on the crankshaft.

  Probably far easier is to just install the 2.1 accessories and controls on a 1.9 case, and call it a wash.

  Jonce Fancher <streetbugs@WHISPLLC.COM> wrote:
  Hi all
Will 1.9L pistons and cylinders bolt up to the 2.1L engine.
Or can I put a 1.9L motor in a 86 Vanagon?
I just have alot of 1.9L items but found a 86 with motor issues.
Thanks
Jonce

Jonce Fancher

56 Single Cab
66 Sunroof Bug
66 Variant Squareback
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84 Vanagon "Gottfried"
85 Vanagon Westi
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