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Fry Rice Specialist
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Discussion Starter #1
what is it mean actually by blueprinting the motor?

i heard that a lot but can't never figured what is it.

any one care to explain it to me?

thanks.
 

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Blueprinting is usually nothing more that machining and assembling an engine and checking EVERY measurement and recording them.

For example, when most people build an engine they use plasti-gauge to check the clearances of the main and rod bearings, which is perfectly good for the majority of engines (even performance engines).

If you are blueprinting an engine you would measure the diameter of each journal at 6 locations (front, middle, and rear of the journal and then at 90 degrees to the other front, middle, and rear measurements) and also measure for any run out. Then you would measure the ID of the mounted bearing inserts at the corresponding locations of the journals. This would give you the exact amount of clearance for each journal at the front, middle and rear of the journal.

Once you have those numbers, you can then machine, or “mix and match” until every part of the engine is the same as every other part AND meets the clearance/tolerance that you are looking for.

Some people consider “blueprinting” to also mean using different tolerances, but IMHO, blueprinting is just measuring, adjusting accordingly, and recording every measurement. Using different clearance tolerances is all about the application and not a function of blueprinting (at least that is my opinion).

This is why blueprinting an engine is so expensive. It’s not necessarily “better”, but it is horribly time consuming… Labor = $$$$$ :beek:

But when you’re looking for every ounce of power and reliability, you can’t do much better than “balancing and blueprinting” and engine. :thumbsup:
 

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Fry Rice Specialist
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Discussion Starter #3
thanks a lot for the explanation. it instantly hit the spot for me to understand.

it means unless you have lots of time and sensitive measurement and weighing tools then it is basically impractical for daily driven engine right.

just wondered what is the price range usually for blueprinting service?
 

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Every engine should be "blueprinted" .. even if its grandma's grocery getter, or a race engine.

Its just a matter of making sure the tolerances are within specs, instead of just throwing the engine together. It really doesnt take that much time, and you dont really need special measuring equipment unless you plan on doing a few engines.

- Dan
 

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Refrigerator Raider Hater
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Every engine should be "blueprinted" .. even if its grandma's grocery getter, or a race engine.
Not economically feasible. Mass production simply sets each part within tolerance, and therefore every measured spec should be within tolerance.
 

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Unless they hand you a document with the measurements on it, then IMHO, it wasn't "blueprinted". :thumbsup:

I have heard many, many shops say they "blueprint" an engine, and all they do is check the basic clearances, but not in sufficient detail.

As another example of a test that probably isn't done on a lot of modular rebuilds is checking the RA of the heads and block. Most shops don't have the test equipment to perform that test. But yet they may tell you they "blueprinted" the engine. How did they blueprint it without taking the measurements? :2huh:

If someone charges more for "blueprinting" an engine, I would expect a document with lot's of numbers on it. :thumbsup:

But that is just my opinion as I am surely not an engine building guru by any means!!! :D
 
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