YEah, I keep forgetting- the ground pin is good for ~4-5psi.

DP

 

Update
I went on a longer drive this morning the temps were a bit cooler out and to my surprise I was able to get up to about 24-25# like before. It just took what seemed like forever to get up there. I saw about a 50 deg. reduction in EGT crusing at 65 with an avg. of 3 psi boost . From 0 to 85+ mph WOT max egt was 1100deg. I think this is probably normal.

Thanks guys for the help..
Mike

 

All else being equal, the larger 60mm compressor wheel will be a tad slower to spool, so your results look right on.