I’m trying to repair a racetrack blow up. Ive got two motor options to work from. Both motors broke eagle aftermarket cranks while spinning 7400 rpm.
Motor 1 is 355 mahle flat top forged pistons 6 inch scat rods broke crank and timing cover and front main is blown clean off the block. I have a .030 block and I’m consider assembling this short block with a stock cast crank. No rods or pistons were damaged.

Motor two Is .060 flat top probe industries pistons, 6 inch scat rods, block is scared on one cylinder wall below the travel of the piston and otherwise visually not hurt. 3-4 rods and pistons are ruined. The probe piston company is out of business and I’ve not seen probe .060 flat top forged pistons for 6” rods available . A positive thing about option two is the block is saved. The blocks are bored, decked, line bored, studded etc.

Assume both motors ran well for 25 nights of racing.
Questions to start with


What limitations have you observed for the stock Chevy cast cranks for two barrel motors revved to about a 7400rpm-these motor rebuilds are irresponsible gambles and therefore must be inexpensive. To my line of thinking it Doesn’t make much sense to start the build with a 600 dollar aftermarket crank.

Is the bob weight of a stock cast crank a concern. Can this be adjusted by a novice without a gram scale or any other machine shop

Can the stock cast cranks accept the OFFSET rods the same as an aftermarket crank no problem-the journals are the all standard on these motors

Is there a technique(diy) to understand how much the destroyed block has been decked exactly to duplicate this or does the motor need preassembled and measure and the block then taken to the machine shop (option one) also what does it cost to deck a block guesstimate.

For short block two is there a replacement piston that matches the probe close enough that I could consider either buying 4 and running missed match. Or is there a replacement set of 8 that is known to work on the block deck height(zero deck now with probe) I haven’t found numbers on the probe maybe 12335 reading on the internet but I cannot confirm.

Need some ideas on how to best do all these things a guy shouldn’t do.

Bedtime