>From schwarze@superc.nosc.mil  Tue Jan  3 13:06:34 1995
>From: David Schwarze <schwarze@superc.nosc.mil>
>Subject: Re: motor swapping

Christopher Bridge writes:
> 
>         We would all like to get our VW's greater hp with the least effort.  
> To build this size ( 1835cc 92mm X 69mm) engine you must split the case to 
> have the case bored.  It is true that there are "slip in" kits for 87mm and 
> 88mm bores.  With a stock crank, this gives 1641 and 1678cc.  The 87mm is a 
> safe way to go- altough there are as many opinions about motors as there are 
> people.  The 88mm is generally not recomended.  There is some confusion on 
> what flycutting is.  Flycutting removes metal from the large flat area on 
> the heads.  This is done to either increase compression ratio or to flatten 
> the heads-cylinders mating surface.  Under no circumstances have your heads 
> flycut to increase your compression ratio- this is a great way to burn up a 
> motor.  To fit the case and heads with the 92mm jugs both the case and the 
> heads will have to be machined.

Thanks for the correction Chris.  I didn't mean to imply that the compression
ratio should be increased - merely that the diameter of the combustion
chamber be increased.  I was also wrong about not having to split the case.
I forgot about having to widen the holes for the cylinders... DOH!  

As for terminology, I always thought "flycutting" referred to the use of a 
circular lathe to widen/deepen the combustion chamber, whereas "milling" 
refered to removing metal from the large flat area on the heads, usually 
done by running the head across a different type of lathe which removes a 
couple of thousandths each pass.  Milling doesn't do squat to VW heads
though, cause the mating surface is recessed.  In any case, you are correct
on all counts.

-David

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David Schwarze			'73 VW Safare Custom Camper (Da Boat)
SAIC Comsystems, San Diego	'73 Capri GT 2800 (Da Beast)
schwarze@nosc.mil		'87 Mustang Lx 5.0 (Da Bruiser?  Soon...)
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