Not in this particular design, because the water-jacket sizing between the
case and the head(s) is the same. The differences are internal, vis-a-vis a
different piston (in height) to compensate for the increased stroke. The
piston diameter is the same (I believe 94mm).
 The difference in the headers (both stock and S&S) relate to how the
mounting tabs for stabilization bolt on to the engine. A 1.9 exhaust works
just fine on a 2.1 provided it is entirely used from the head(s) to the
tailpipe. I run a 1.9 exhaust system on my 2.1
--
Jim Thompson
84 Westfalia 2.1 "Ole Putt"
73 K Ghia Coupe "Denise"
72 411 Station Wagon "Pug"
oldvolkshome@gmail.com
http://www.oldvolkshome.com
**********************************
On 11/8/05, George Thorburn <thorgk@accesscomm.ca> wrote:
>
> >>I wrote this up after doing a 2.1 upgrade my 84 Westy in 1997.
>  Jim,
> Thanks for the link. My 1.9 is running good but if I see a 2.1 motor
> available I might snap it up. I thought the exhaust headers would need to be
> modified. I have the S&S headers on my van and if I recall they sell a
> different set for the 2.1 motors. Doesn't the longer stroke put the heads
> (and exhaust ports) further apart?
> Thanks again,
> George
>