Funny I should stumble onto this thread, as I'm installing a 164 3.0 into my 116-series GTV6 these days. My 3.0 is from an '89, so it's a 12v-engine. Main differences are that the 164 is fwd, GTV is RWD, so a few transplants is in order (using parts from "old" 2.5):
- rear engine mount
- plenum (164's can be used, needs som alu-welding, though)
- left and right engine mounts
- starter engine
- top part of thermostat
- oil sump
- oil pump
mmmmhh... that's pretty much it..
And, og yes... it's a "bolt-in" MY A** !!!!! wink
Prepare to do the unthinkable, and apply brute force, misc power-tools and (have mercy) aluminium grinding tools to the 3.0.
Ex.: some machining needed between cyl.-heads to get clearance for 2.5 fuel-rail.
I'll use this 12v as a "in-between" until I can get ahold of a 24v, preferably a late 90's model.
I have instructions and appx costs for installing a 24v into 116-series, as per Joe Beninca (Aus). He runs'em regurarely at 400hp.
Check link for video, prepare to want one...
24v Dyno Accel - appx 1.3mb