The 993 engine has smaller exhaust ports I believe.
Also, the 993 pistons cannot be machined down.. only the 964 pistons can be, to achieve ~8.25:1 C/R.
My vote? Get the 964 motor
It only costs $20-$25 per piston to have shaved. They should also be balanced after the dome is trimmed &
Valve pockets would probaby be an extra $90-$100
'89 911 Turbo Cab
Protomotive MAP ECU, Twin Plugged Heads, GT2-EVO CAMs, 3.3L fully finned P&C's, ARP fasteners, C2T head gaskets, Titanium Retainers, Turbo spec valves, springs & guides, 964 splash valves, GT35R BB turbo, GSF Stainless Headers, Magnaflow Exhaust, Full bay Intercooler, TiAL 46mm w/gate, TiAL 50mm BOV, Apexi AVC-R EBC, SPEC Stage3+ Clutch kit, Crane CDI Ignition
Last edited by WydRyd; 02-04-2007 at 08:53 PM..