Help me pick my engine! Update: engine picked!!

[71chally416]

Sonic check the block before you start investing $$$$ in it.

[moper]

Actually, that rust is the light colored stuff. It looks worse than it is in most cases although this is the internet and one never knows. The pistons look like stock replacements to me. Not high compression ones. If you are not going with a 4" crank, I wouldnt bother sonic testing either. Just mag it and go .040 over. If you need to go .060, and need to make a bunch of power, sonic test it. I find the 73 blocks are best to go .060 over safely even for 4" arms. Early ones will have more core shift.

[72bluNblu]

Nah, going to stay with the stock crank, if I'd wanted to spend the cash on the stroker I'd have just bought the guys 360 block for 50 bucks. The 340 is just cool though  , just has that extra nostalgic factor. And in '72 it was actually an option, in case I want to go with a rally clone later. As for loads of horsepower, I don't think I'm looking for anything that extreme. Hopefully between 350-400 hp, which should be fairly simple with decent heads and cam. On further inspection the bores actually look pretty good, the rust in the pictures is just the surface flash variety. The small ridge at the top is likely the biggest issue. My fingernail catches on it, but it doesn't look huge. Have to see what the machinist thinks, I'd like to be able to just go out to .040...

[71chally416]

I had a 318 that was .040" over and I used the $80 a set Badger cast pistons PAW used to sell. It saw 7,000rpm more than a bunch of times and I never had any piston failures. (It didn't make much power there but I was showing off for my friends  ) I even had nitrous on it for a month. I think a 340 will be fine at .040" 

[72bluNblu]

So I pulled the oil pan and windage tray to take a look at things. Looks like a forged crank as advertised, and the bores look good from the bottom. No ridge at the end of the stroke, just a different texture as it goes from the worn part to the cross hatch. Can even see a few deeper cross hatch marks in the bores in the worn areas, the ridge at the top seems to be mostly carbon. Won't know for sure until I can get it to the machinist, but I think this is good news.