I see you have a nice new FMS crate motor. Now I don't want to ruin you Christmas but here's my 2c's worth. I believe that the crate motors are built on the same assembly line by the same people who put together the current production motors at Ford. What they do is select internal parts based on parameters such as rod weight, piston weight, crank journal size etc. Then put the pistons that are about the same weight and the rods that are about the same weight into the motor. I say about because they are not the same weight just in a band of weights. They do the same with piston size and ring gap. About close.
What you end up with is a motor that has all new parts that are "about" in balance.
Mine (345HP 302) lasted 3000 miles. About 300 of it was on track with a rev limit of 6K.) The rear main bearing spun and hurt the crank enough that I replaced it. As I took it apart I made every attempt to measure everything. Several rod bolts were down to 10 Ft/lb's, ring gaps were all over the place, and a couple of the the bearings had what I would say were excessive clearances.
I have a cannon 7 quart pan and a oil cooler system with 8 1/2 quarts total in the car. It wasn't oil. I have run the same engine for about 600 track miles and another 5000 road miles since the repair (New crank, damper, complete rebuild/ full balance, same pistons and rods with ARP bolts. Runs good now.
Now you can put some of this down to the vibration that resulted from the spun bearing but ring gaps don't change because the lower end eats up the main bearings.
So now that you have all those brand new parts I would recommend that you take it apart and have a reputable engine balance shop balance it for you. You will more than likely be able to reuse all of the parts except the bearings and rings. I would put in some good high per rings and take out the stepped rings that FMS uses if that is what you find along with ARP rod bolts when it goes back together. I would closely inspect the heads, especially the valve spring retainers etc. But otherwise bolt them back on when the engine is put back together.
All this is especially true if you intend to use anything other than the flywheel that came with the motor.
These engines work very well in hot rods that are really boulevard cruisers. Or only run hard for a few seconds at a time off of stop lights etc. They are not intended for track use and FMS will tell you that. Good parts, just not assembled carefully enough for extended hard use.
Ya, I know, I didn't believe it either. But for a few hundred more you can have a fine engine that is balanced properly. It's not now, unless FMS has drastically changed their process.
Please don't think I am criticizing your engine choice. I made nearly the same one. I just saying that you can't expect a blueprinted engine from a production line assembly operation.
