When someone says that they blue printed their motor what does this entail ? I thought it was just clearancing rods, mains, rod end gap, piston to wall, check the line bore, and maybe oil pump gear clearance ? Is their more to it than this ?

 

Here is a good explanation... http://everything2.com/node/1276402 94

 

In the good old days there was usually quite a bit to be gained from blueprinting engines because the manufacturing tolerances from the factory were quite sloppy (with most manufacturers). These days (last 25 years or so ?, at least with Japanese stuff) there is a lot less to be gained because factory manufacturing tolerances are so tight (especially with Honda).

 

If you look at the measurements in a Honda shop manual in conjunction with the markings on your block. That is as blue printed as you are going to get. Put your engine back together with all new bearings and seals using these tolerances and voila you have a stock "Blue Printed" engine.

Start messing around with a stock engine and turn it into a high revving N/A engine, a Boosted beast, forged parts vs cast. Then you will need to think about blueprinting the engine according to those specific parts and or applications. Not to many engine builders are going to give there blue prints away for special built engines though.

 

To expand on what I was saying; blueprinting (only) a Honda engine (or most other engines these days) will gain you almost nothing but cost an arm and a leg. You might not even change anything (probably wouldn't), but spend a lot of money just measuring things. Most if not all aspects of the motor will already be within the parameters acceptable for a race engine.

One place it may be worthwhile (if the engine is already apart) might be to match manifolds to ports etc to smooth out gas flow (particularly on the intake side).

The stock components in most modern engines are as good, or very close to as good, or in some cases better than the 'special' competition parts that used to be neccesary when modifying older engines. As an e.g.; when 'building' BMC 'A series' engines (Mini, MG Midget, AH Sprite etc etc...), you needed to junk just about every moving part and replace with better 'competition' parts (or the best of the stock components from within the range - e.g. Cooper S parts etc-, checked, 'selected', magna-fluxed etc etc), as well as checking every single dimension of the engine, many of which would need rectifying.

Failure to use the right parts and assemble the engine ultra carefully would mean the engine would fail, or the rpm would need to be restricted. These days engines are very well designed, manufactured from very high quality materials to very tight tolerances, and as a result are very robust. Modern engines will typically handle a large rpm and power increase without needing to even think about the bottom end, which wasn't the case in the good old days...

 

My sentiments exactly.