i am installing some dre coilovers on my truck this weekend and was wondering if it was possible to flip the hats on a 2wd with stock A arms. I would like to run little to no preload but retain the height from the leveling spacers that I was running.
My guess is that using the stock UCA's, you wouldn't be able to grind away enough of your coil buckets' lips to avoid a lot of contact, even on road. The DRE/Icons are already longer than stock struts, and then the hat flip adds another inch and a half, (which is the same as adding a 2.5" leveling kit).
The preload in the 2" range isn't bad at all. With the hats flipped the front was at a little over 4", and had reverse rake, so took about an inch of preload lift off, and didn't notice any difference in the ride. Also, reducing preload, doesn't reduce bucket contact, because it doesn't change the strut length.
Since the un-flipped DRE's are a little longer than stock struts, you can probably get an equivalent of a 2.5" leveling kit by setting the threads on them for 1" to 1.2" for about 2" of lift, and still have a nice ride.
I had the Total Chaos UCA's on my Titan and still had to grind the bucket lips a bunch. Finally got it down to where it wouldn't hit on most big droops, but it still touched when I jacked the truck up. I wouldn't consider doing the hat flip again unless I was running PRG UCA's since they provide the most clearance. I might have a custom spacer made to give something like 1-3/4" of lift, but I think 2.5" is too much for the Chaos arms, and way too much for stock.
Un-flipped as they came from DRE, (and now Icon), they work fine with the stock UCA. I ran mine like this for a year or so, until Greg, at PRG, completed the performance package on it ... that included the Chaos arms and a net 1" lift spacer, which gave mine about 3" of front lift. But even the 0.67" thick spacer was too much for the stock UCA's, which is why the kit had the aftermarket arms.