According to me:
If you're buying 4340 stuff and forged pistons there isn't a really bad choice out there. I don't think there's a spits worth of difference in the cranks, IMHO the raw forgings all come from the same place, also most rough machining is done in the same place. It used to be that Scat had better QC on the finished journals, but there have been several posts in the last year that said the others measure true and round.
Connecting rods I am sure the H-beam forgings all start out the same. Different companies machine them a little differently. I-beams (I prefer the style) may start out with different forgings. Either way they are all stronger than stock and the 7/16 rod bolts are what Mopar should have used in the beginning.
Now if you're building something that will break a stock block then my words have less value. There may be some better than others. But for a street sometimes strip car that runs 10.0s or slower I see no appreciable difference in FUNCTION.
Pistons are nearly the same, it depends on what you need. One brand might be a little better fit in terms of comp height or valve notches or whatever. But again if you're 10.0 or slower, JE or Wiseco or Diamond or RaceTech or Ross or Icon will get the job done.
We are living in a golden age, one can buy parts to do nearly everything for far less in real dollars than ever before.
So find some person on the other end of the line that you can talk to when you need to, and buy from them. Then pay the extra money to have a local machinist check all the parts and plan to do a little fixing, like piston pin bores can need tweaking.
Even if you buy a prebalanced kit, the sizes still need to be checked. Balancing doesn't include checking things like rod bore sizes or crank throw sizes.
R.
Many successful engines have been bought mil order, slapped together and run without any kind of check, but there are lucky folks out there. If one puts $1500 in a set of parts it'd be smart to do a little checking before assembly.
My
