Will these work?

[Finallall]

Will these fit my 87 3.8 NA block?

SBC 350 .100 Dome .020 Over Hi-Compression Pistons & Moly Ring - Edmonton Engine, Engine Parts For Sale - Kijiji Edmonton

Thanks.

 

[WarWagon]

No. for many reasons here are a few:
The Buick 3.8 v6 has a 3.8" bore stock, The SBC 350 is a 4" bore stock so think about that then think about the fact that these SBC pistons are .020 over 4" now too, Huge pistons. These SBC pistons also have a .100 dome, the Dome is going to be wrong for the Buick combustion chamber.

Federal-Mogul Buick 350 pistons Will work with a re-balancing of the rotatory assembly.

 

[CamoDeafie]

I am also told that the L36 and L67 pistons will work; but you need to change rods...also; pistons for the L27 and LN3, LG3, LK9 maybe LN7 applications will also work, with rod changes..L27 being Series 1 3800, LN3 being pre-Series 1, 3.8 but marked 3800 on some, LG3 being the FWD 3.8s i think those are direct swaps with rods and all for the RWD buick v6s...LK9 and LN7s are both 3.0L v6s, i think the LN7 has a shorter deck height and a dished piston top; shorter rods too....LK9 being the 1982-1985 carbureted 3.0 v6s, same bore size, taller deck, 3.22" stroke i think...as in shorter rods. someone mentioned that the LK9 pistons with the 3.4 stroke rods would yield like 12 point compression ratio; so might need fiddling between various rods....and cranks.
in short, Buick 350 and most 3.8" bore pistons with same pin offset will work. piston compression heights may differ between models; LK9 and LN7 have 1.800-1.805 PCH; same pin offset; not sure of other pistons; a friend was able to use L36 pistons but LN3 rods in a performance LN3 NA build; I presume it would also work in the RWD 3.8s, he achieved 9.8 CR on his LN3 build....pretty good; a jump from 8.5-8.7:1 compression