40 hp Judson question with a 69 mm crank

[Ojai63dbl]

This I am sure can be located in SAMBA, but a quick search yielded only a little insight

Question
If I run a 40 hp with a 69 mm crank(1600) in effect I get a stroked 40 hP.

77 mm pistons yield ~ 1300 (instead of 1200, a 10% boost)

83 mm yield ~1500


according to:

http://www.thesamba.com/vw/forum/viewtopic.php?t=338517&highlight=crank

Whats the catch I am not thinking about here
Is there a drawback of going to the 69 mm crank on a 40 hp engine?

It seems logical since you can counterweight it to get harmonics down and the 1200 cranks are getting old.



Now the REALLY important part of this:

Can I still run the Judson on this setup and get boost with the 83 mm pistons or the 77 mm pistons installed

- or would I need to oversize my judson pulley to spin it faster (which would mean more heat -not good)





THoughts?

[Eric Outland]

Ojai= Larger Pully =spin faster= EXCESSIVE heat!! You can run it on with whatever you like, but the judson supercharger was designed for the 1192, or the 40hp Judson pusher and you start putting more load than designed for and the little supercharger vains just create more friction ( even when you adjust your Marvel Oiler to put out max Lubrication). You may get away with 77's and O.G. Pulley. But then again your changing in essance the thickness of diameter of Barrel however so slightly and that warrants a differant set of issue's all together. Hey anything is worth a try! You might get Lucky