- tell me more about blueprinting. I didn't know that it was something that can be done with a production engine. How much did it cost? How long did it take? Got any pics?
Blueprinting is a lot of money as it is the process of checking and adjusting all tolerances by hand which is a very long process. Typically a mass produced motor will only be accurate to maybe the nearest mm if you're lucky, in some cases manufacturers quality control could be putting out something that's over 2mm in tolerance (GM are ****ers for this apparently). In essence you're trying to make a motor exactly how the millions of £'s R&D budget intended. I do concede however that modern day manufacturing techniques and quality control put a 'stock' engine a lot closer to a 'blueprinted' engine. A simple porting and polishing job on a head unit can probably yield a slightly lesser result for a lot less money/time.
Balancing is slightly different as you're major goal is to ensure the balance of moving mass within the engine. As speeds increase an imbalanced weights effect will increase at an exponential rate. All imbalances WILL sap power output. I don't have time to get my whiteboard and marker pens out to draw a vector diagram of this but this:
where the horizontal is actual measured output, vertical would be any parasitic factors such as imbalance and 'vector A' would be the actual work done by the motor. In simplistic terms your motor is working harder than it is perceived to be outputting as vector A is longer than the horizontal.
Now before I get torn to bits on this explanation, PLEASE note that its 19:45, I've just clocked in for a 12 hour night shift and I'm doing this off the top of my head on a work computer without any literature to back up my thinking. If you're going to disagree, be nice about it.
A good example of this is the first set of BMW S1000RR's engines. Whilst they shared many similarities with the 2005 GSXR1000 engine, their level of detail was far beyond which allowed for a substantial power increase. All pistons con rods were matched for weight immediately after production and then 'cold cracked' instead of cut to ensure that they didn't lose any material in the process. I'm not saying that this gave it the monstrous horse power jump but its a great example of how OCD things like blueprinting and balancing are.
Would I ever blueprint an engine on a daily bike? no.
Would I ever blueprint an engine on a track bike? no.
Would I ever blueprint an engine on a race bike? probably yes.