What are you trying to accomplish? For a stock engine you can do a little bit of fine tuning but there is very little benefit and if you a person that likes to drive at higher speeds you will make some things worse. Contrary to popular belief lowering the engine can actually reduce your top speed. The stock set up is somewhat gear bound with the top speed generally limited by wind resistance and available horsepower. Horse power is a function of torque and speed. Lower the engine speed and you lower the available horsepower. Especially on the Syncros and automatics a change as small as going over 27" tire diameter makes this evident. 

Lowering the engine speed at a given road speed means more force (torque) is then required to get the same work done (wind resistance and hill climb). This increases cylinder pressures, bearing loads, production of nasty NOx emissions along with increased tendency for the engine to go into pre-ignition, (knock). On the driveline side this increased force results in increased wear or some parts failures. The transmission is undersized for the load and speed already. 

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Dan N
Sent: Thursday, September 3, 2015 2:35 PM
To: vanagon@GERRY.VANAGON.COM
Subject: regearing a manual trans

hi all,

I understand the concept of regearing the trans with a stronger engine, more HP (conversions etc..)

but what about regearing the trans and using the plain old 2.1 WBX? any benefit?

any idea?

thanks

dan