What is blueprinting an engine?

[gh6o6]

well i always hear about blueprinting an engine but yet i am confused about what it is.  i originally thought it was selfexplanitory - like maping it but i need a more detailed (or the correct) definition

[Silviaboy]

Blue printing is the process of going to the original "blueprint" of the engine and to bring all the coolant and water passages to the original tolerences and removing all of the left over metal peices in the block left from the sand during the casting process. It also consists of torquing the top of the block as if the head was torqued on. The cylinders are then honed so that they are perfectly round. When blueprinted is mentioned usually balancing of the internals is also performed. This consists of conecting weight to the crank that is equal of the piston and con. rod assembly and matching that weight with the weight of the conter weight on the crank. Also before that the pistons and rods are matched from side to side so they are symetricly ballanced. A balanced and blueprinted engine is what the engineers at the factory intended. It removes any errors and will make your engine handle higher boost and last much longer since everything is equal and not lop-sided.

[nos240]

i could be wrong, but i thought blueprinting an engine was to measure all internal moving parts for right specs and tolerances. like measuring crank and cam journal for warpage or out of round. stuff like that. i think the important of blueprinting an engine is to get proper oil pressure. this is something every engine builder do, making sure everything is torqued down correctly and within specs and tolerances.

[crazycuban]

yeah, nos is right.  its checking the tolerances of every part to within micrometers.

[sspikey]

yeah thats what ive heard from the local engine builder also.

[nos240]

i guess what silviaboy is talking about might be something that engineers do when they're designing an engine.  

[Gesturewomotion]

nah... silviaboy has it right. you balance and spec everything to exactly the same tolerances so everything is the same. the basic way to look at it is this. take the block that's been balanced and blueprinted and the block that's factory new stock and set them both on a motor stand. grab the balanced and blue printed block's crankshaft and you can spin it freely and it will free spin for a good little while as well. the factory put together block will hardly move. and it will not spin freely. does that make sense?

[DSC]

would doing this yeld any HP or would it be one of those things the just allows you to up the boost? Would it be any good for N/A tuneing? How much would this cost?

[sspikey]

i heard it was basically having everything precision machined to exact sizes.

[sexy240]

Blue printing is just as silviaboy said.  when an engine is casted some of the original design is lost. a blue printed engine will have all the little imperfections polished out.  this will allow the oil to flow better ect ect...


a balanced engine is good for any high power application.  it becomes more and more important as RPMs increase.  

I think  (not sure) that a perfectly ballanced engine would not need a harmonic ballancer.  but then again the harmonic balacer is made to cancel out the frequency caused by a crankshaft.  So  I dont know

[crazycuban]

silviaboy is partially right, nos is partially right - you put a torque plate on the engine to simlate what it's like with the head on, round the cylinders, hone the cylinders to give it a cross-hatch pattern for better oil flow, machine parts to the tolerances the engineers designed, make sure coolant/oil passages are all good, and if not bore them to spec, balance rotating assembly (crank, rods and pistons), take off the casting or forging marks created when making the engine (they create stress risers - - easy places for parts to crack), make sure all bearings and other parts are ok, etc....

doing this would yield a LITTLE bit of horsepower - your engine runs better.  its the same type of horsepower something like redline oil will give you - its not increasing the flow of air, or the fuel, its simply making things run smoother.  on race n/a engines, this is extremely important.  an engine that spins to crazy high rpm's creates more stress on moving parts, making it critical that all moving parts are in the top condition possible.  on a turbo engine it's important as well, as when you boost, things break, and this makes your engine more bulletproof.  it's mainly a reliability thing.  

if you have a near-stock engine, then blueprinting is a waste of time.  if you're going in to get pistons or rods lightened, your crank knife edged, or upgrading the valvetrain, which will all allow higher rpm's, its a good idea for that little bit of power it gives you, because your engine is at a machine shop anyway, and most importantly, because high-revving engines get unreliable.

[gh6o6]

i dont want to do this, i just hear it talked about in magazines for race cars and was curious about it

[240booster]

what kinda $$$$$$$ moneys r we talking about here ....   sounds ungodly exspensive???

[tnord]

2-3 grand for all labor and machine work, 500-1000 for just machine work; meaning you take apart the engine and put it back together yourself

[transient]

Sounds worth it to me.

[tnord]

it's worth it for wheel to wheel club racing, but street applications it's really not