Question about 1g/2g turbo engine

Hi guys, one of my friends has just bought a 2g earlier gsx(i don't know if it's a 95 or a 96 but this is not a problem) and he's looking for make a swap with 1g gsx engine.........ok, he know whats he got to do because he has just do a swap but we got a question about the difference between 1g & 2g engine block.
We wanna know if the only one difference is just the head or if also pistons, and the other internals are different and in this case better than the one in the 2gen, because he don't know if make only an head swap, or sawapping all the engine block.
If there are some other differences can you wrote down in this thread please.
thanks a lot

i do know that youll be losing about 15 hp putting in a first gen engine in a second gen body, and the second gen is a little heavier also. you should just stick with the eng gen engine; use a blow off valve from a first gen cuz theyre not made out of cheap plastic.

http://www.darklightning.com/gi/1gvs2g.htm

do the 1g 6bolt swap.

ps. i had a hard time understanding what it was you were trying to ask. please try and edit your post to clean things up a bit. it might help you get better information.

yeah...i'd do the 1g Head swap, cuz of the 6-bolt engine.

Mr WhiteGST99 seems to be Italian, so I can see why his wording seems odd :) Could be wrong though.

You can do the 6 bolt block swap and use either head. Its a pain in the ass to use the 2g head because you have to increase the head bolt holes by 1mm. Its a pain in the ass to use the 1g head beacuse you have to convert the whole cooling system over (not the radiator) to 1g parts. Saying that you will lose 15hp with the swap is incorrect, since no one doing a 6 bolt swap is going to be using all stock components ;)

The 1g block has a different bellhousing pattern, but it is compatible with the 2g tranny, just can't use one bolt. The pistons are 7.8:1 compression vs 2g 8.5:1. The rods in the 6 bolt are stronger, and the crank is different as well (thats where the 6 bolt/7 bolt names come from). The 1g head flows more, but the 2g head may offer better low and midrange power. People have run sick times on BOTH heads after all. The 1g head must be used with the 1g manifold also, and the 1g TB is a good idea. 1g stock cams are slightly better (91-94 turbo only) than stock 2g cams.

Yes Kevin i,m from italy, thats why my enghlish sounds funny, thanks a lot for the explanation