Quote Originally Posted by 34coupe View Post
Hi there, I just joined this site to reply to your post.
I'm in England and have owned a block with the same number as yours for about 25 years.
I bought it along with an unused 69 zl1 block which I now have in my 34 coupe.
Only this week I pulled the steel block out to see what I could do with it.
I couldn't identify it by casting number so I googled the number and your post came up.
What I can confirm is that it's a 4 bolt mains truck block with the taller deck height..it has HI PERF TRUCK PASS cast at the front inside the timing cover.
Mine seems to have a stroker crank in it..it's numbered O-250157 which I haven't yet traced..it also has KIEKHAFER rods
Best rgds
Paul mason
kiekharfer rods are older set of rods but are still a very good .on crank may tell you more on the front of the counter weight as for who made it like modex many did use the gm raw core to start with gm cranks could only take a 4.250 stroke that i know of , all bbc said Hi per /pass most 9.800 decks . some of the tall decks 10.200 did say truck /marine and just truck not to much of a big deal all truck block do have 4 bolt mains