BBC OEM crank, rods HP capcity/build... sugestions please

i would buy new make sure you ave it balanced buy some better pistons then kb crap.

700HP on a stock cast crank sounds kinda nuts to me. Hopefully it's true since that's about what I'll be making when the bottle goes on my 454!

For what you're doing a stock cast crank is fine. Nothing wrong with KB Hypers as long as you're not boosting or hitting it with spray. I've beat the crap outta MANY sets of KBs and never killed a set until I started playing with the roots blower combo in my 78 Malibu. It took a while to learn how to tune a combo like that and I killed a few sets due to my own stupidity (tuning right into detonation, which they can't take for very long in a blown/nitroused application). On a modest N/A engine you'll probably never break them if you mind KBs special specs for top ring gap.

700 hp is a sure way to send that cast crank through the pan in about 5 pieces! Get a new crank, have the bottom end balanced, especially with big blocks. A 10:1 bbc with a decent set of heads is easily capable of upwards of 500 ft. lbs of grunt and around 400 hp if the heads and cam are matched up properly. More than enough for a DD!!

Simple recipie for a daily driven street deal... I have this motor in my 70 camaro, Dyno'd right at 500 hp and 525 ftlbs... runs 11.80's in a 3500# 70 camaro.

std bore 454 (i had a marine virgin block laying around) stock marine forged pistons with a little pop up like .125 cast crank, stock style dimple rods, good rings.. Heads are a mild ported set of 781 casting numbers, untouched performer RPM air gap, 850 holley and off the shelf extreme energy 284 cam and lifters, hardened pushrods and roller rockers... 2" primary headers.. runs on cat pee 87 octane, sounds lumpy and cool and you can drive it anywhere...

I see you have a t56 car listed in your sig.. that would be a TON of fun, 525 ftlbs and you wont even need to shift down :lol:

Wellll... GM used forged cranks in pretty much everything they sold that made over 300 HP, so if reliability is a concern...

Can you run a cast crank in a relatively stout combo? Sure. It's more a matter of how long you intend on running it.

Tommy

Stock crank and rods will handle your goals. Don't worry about a 30 under crank. Tests have shown when correctly ground there is little difference in strength. Radius' done right are the key. Rods are forged. Put ARP bolts in the when reconditioning. Take it to a shop that is usually busy. I have seen many cast steel cranks take a poop and would not run one. Keith blacks should be fine unless you spray. Spend money on good machine work. "0" decking the block, ARP main bolts or studs and align honing, I would balance too if its the budget. Ask the shop if they can do these things too. Don't be shy, its your motor or grenade.