IRRC, the domes in the CIS pistons are not very thick and cutting valve pockets, while it can be done, is tricky. So your max lift is limited. With out the CIS you get rid of the overlap pulse issue so you could increse the overlap.
You could certainly replace them
Then you could go radical ... but that is $$s
-Michael
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Michael
'82 Euro SC 'Track Rat' 22/29 Hollows, 22/22 Tarrets, Full ERPB F/R, Rennline Tri Brace, Glass bumpers, Pro 2000's, 5 pts, blah blah blah
'13 Cayenne GTS