I don't see much discussion on this nowadays. Do most people buy parts and assemble them without any prep? When you order a rotating assembly, do these typically come B&B? And if so, what is the min industry standard for this in terms of tasks? Just curious what the standard is these days as I never read about these things in detail.

 

I'd say most buy and assemble without prep. I've not built a motor in years. The last I did build was blue printed. Down to storing parts in plastic bags after cleaning.

 

This is probably a dumb question, what does blueprinting mean? I understand the balancing part.

 

Basically a checklist for building an engine. Torque oil pump bolts - Check. Main bearing clearance - check. etc....

 

My rotating assembly is at the machine shop as we speak and I am getting them to balance it. IMO you have to much riding on how those three main components work together you might as well give them the best chance of survival as possible

 

It is an exagerated term that most people use when they talk about their engine to make it sound better. Everyone has their own idea of how indept the meaning of the term "blueprinting". It basically envolves having expensive measuring equipment like micrometers, dial bore gauge, feeler guages etc. You basically are not just trusting that the parts were machined perfectly and assembling it because all machining process have tolerance or room for error. You are checking piston to cyl wall clearence is right where you want it, hand gaping rings, checking that your block main journals are straight and that it doesn't need to be line honed, checking bearing diameters with everything torqed in place without being installed, micing every crank journal and checking in corespondence with the associated bearing for proper clearence, checking for crank run-out(making sure it is straight), checking crank end play, etc, etc, etc...
This is just an overview. Most people just have their rotating assembly balanced and throw it together and call it "balanced and blueprinted" though.

 

don't forget deburing the block, making sure every oil passage is clear for return, remove and smooth any cast marks, for some it is the only way to build a motor like a religion, for others it is just slap it to gather and run it like it is.

 

The checklist could never end!

 

I was hoping someone would mention that

what about piston prep?

 

Yes normally in a hi-po build a machinist/assembler will check the piston ring grooves and as mentioned earlier, hand file-fitted(gapped).
I myself have a set of JE pistons that are new paperweights b/c the 3rd ring land is is 1/32" from the wrist pin.

I balance my motors for longevity/durability especially when they are not stock builds. and I will not trust any companies machining. The upper U.S. brands (Crower,Callies,Oliver,JE, Cunningham and others) are normally close and you get what you pay for in precision parts. Imports lack q.c. as I've seen rods be out .003-.005 out of round and new forged cranks needing turning .010.

Off my soapbox, and hoped that helped a little.