Originally posted by WC
Stock (friction) shocks can be lowered by adding a stack of 3mm washers inside. They are also a bit too long to allow full compression of the suspension... so you might want to do your own investigations as to how to increase suspension travel.
If you've added oil shocks... yes, the standard "Mini CVA" or any of the alloy equivalents is same length as the friction originals. I use the "Super Mini CVAs" which are shorter-bodied, to allow full suspension travel. Yes, insert spacers, washers or o-rings inside the shock to reduce rideheight.
btw, there is zilch handling difference between a mini with friction shocks and one with oilers. They still just drive the same! 
With rideheight at 5mm and allowing full suspension travel, your tyres run flat & you will banish all chance of traction-rolling even with grippy HPI Mini X-Patts.
Thanks! I'm using the stock friction shocks. I thought these cars where non adjustable, I was wrong. WOW! the handling is so much sharper! Almost like the 1/12 scale pancars. I also put in some stiffer springs. This little Mini is the most fun rc car I've ever driven!