LilCe98 just PMed me on NECO about this thread- So this is the first I've seen of it.
When I found out that the NPG adapters were a reality, I was very interested in them for obvious reasons. I gave both LilCe98 and Sick2000Svt the same set of options:
1) 3L hybrid: Requires welding and resurfacing of the block to plug the oil return holes and B1 supply line not present on the pre-2001 2.5L heads. I am not and never have been comfortable JBWelding the holes or using "Mighty Putty" or whatever the hell that loud-mouth on TV shills. My welder preheats the block before welding to ensure no warpage occurs. That job's too big for my little EconoTIG.
If you're using '01 or '02 heads, no modification is necessary, as they have the 3rd oil return. Just add 3L head gaskets and a full set of head bolts to the list that was posted. Natural compression ratio is above 11.2:1- No good for F/I or basically doing anything else to it.
2) Adapted 3L: 3L block and heads, NPG adapter-LIM that goes 3L oval port heads to 2.5L split port UIM. All we'd need is the NPG adapters, nothing else- Everything from your motor will fit*.
3) Full 3L: 3L everything, including fuel rail, UIM, TB, IACV, EGR. Requires the most fabrication and time, the least "clean" of any install. My first attempt wasn't terrific, but maybe second time around will be better??? Requires extensive modification and more of my time to make it work. Even then, I've seen the IACV hit and dent the hood when you close it.
Then I read a recent addition to NPG's description for the adapters:
**** the LIM fuel rail needs to be 2001-2004 escape only or a VVT mazda 6 fuel rail*******
Fabulous. Obviously, a '01-'04 ANY fuel rail won't be return-style, so it looks like I'll be fabbing the fuel rail regardless. If that's the case, maybe the adapters aren't worth it...