which crank?

[sidewaysXclutch]

allright i have a few engines including a 6 bolt with 90k that has new rings and bearings. i also have a 7bolt engine with 12 miles on it. i heard the 7bolt motors get crank walk alot more than the 6bolt. can anyone tell me does the 7 bolt create less horse power or does the crank walk more often? any other goods or bads that might help persuade my decision between the 2 and i know by milage the 7 bolt would be smarter. any info please let me know i need to drop a motor in asap. also i have a redone block and balanced crank as well and the motor that wasin my car. i could also pull the crank out of 7 bolt and put a 6bolt 2.3 stroker or the balanced crank in? if i do the 2.3 stroker im putting in the other one til the 7bolt is redone. also can anyone tell me where i can get a balance shaft removal kit and does itmake it more likely for crank walk? can i take the one i have out and put it in a different engine? opinions please. thanks for your help.

 

[kahl23]

You need to search before you post, as this has been gone over many times before, but here is the quick and dirty: 7 bolts do crankwalk more often than the average motor, any motor can crankwalk, just the thrust bearing design on 7 bolts made it much more likely. That being said, the rate of failure has never conclusively been provided, but I think the issue is overstated (and I had my crank walk on me). Stock for stock you will not notice much of any difference between the two. 6 bolt rods will hold more power than 7 bolt rods, stock for stock. No, the 6 bolt crank in a 7 bolt block wouldnt work. If you have a 91 though, we shouldn't even be discussing this, the car came with a 6 bolt, put one back in.