Tony wrote 
Has anyone done the offset grind on their 2.1L motor to achieve a longer
stroke?
Has anyone counterweighted their crank?....details?
Has anyone installed a performance cam?....details?
Has anyone done the 2.5L piston and cylinder upgrade on their
motor?........expensive $3,000.....details/
Just checking to see what people have
done......regrets?......recommendations?

Mr. Malibu and fellow learkers 
I have not stroked a 2.1 crank but it is done most time by welding the throws and increasing the offset
you could also grind the throw smaller and use a rod with a smaller big end. I have seen welded crank brake in two at the radius of the welded journal I don't trust welding the WBX cranks and my crank shop has confirmed my doubts he told me nobody wants welded 2.1 cranks for this reason
The other problem with stroking cranks is the wrist pin height you just can't shim the barrel so new piston would need to be made.
counterweighting is an option and in my opinion it is not needed there is no problem to correct the crank does not flex.
As for the non stock cams with more lift and more duration that would make more power at the higher RPMS and the down side is that the lower RPM power suffers. yes the engine breathes better but in a way that make the van less drivable around town. Ratio rocker also gives the engine more top end only.
Bigger pistons would provide more low end torque but this engine does not easily take larger pistons without allot of money and labor. one other problem is that it's hard to notice a few more horse power in a van because it is a big heavy box.
So the question is how do you make more power and not loose drivability and reliability  
As some of you know I have been looking into this for a while and one of the things I have done is to make the engine breathe. This can be done a few ways one is a less restrictive exhaust I'm told S & S makes a performance exhaust that is also a little louder a sign of less restriction. A pair of large carbs would also work but it hard to pass emissions in some states and carbs have there own problems.
 I have chosen to stick with the stock 1.9 injection with my 84 van with the big valve 2.1 engine I have upgraded to the 2.1 throttle body it's  5 mm larger and the center box again 5 mm larger to match the throttle body and the outlets are 2 mm larger as is the runners to the heads. Both the 1.9 and the 2.1 runners are narrow at the head gasket surface and I have been porting both the manifolds and heads for increased air flow and power.  
I have done some flow bench testing with the heads and the stock WBX heads don't flow very well at all. You can see my flow tests on my web page look for the link on the engine price list under the stage three engine. Making the engine breathe is key to more power. The trick is to match the components and to test the output on a dyno.  not with a magazine in one hand and a wrench in the other. by that I mean that the magazines are driven by the advertisers and we all know that the VWs aftermarket is full of add ons that don't work and they keep on selling them year after year.  Seat of the pants is also not a good test for increased performance and I have proven that to my self time and time again         
so the direction I am going in is to make the engine breathe. think about it motor cycles they make big power from little engines. how?  they make them breathe and they spin them up in RPM. Im in the middle of testing, learning and changing and testing and testing keep you posted when I have something to share
Bob Donalds 
http://www.bostonengine.com
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