I understand your wanting for that comparison as I want to see it as well. The reality is, however, its not that simple at all. To accomplish what you're asking, we need to have a built and tuned hybrid car to start with. We then need to pull the motor out, pull the heads off, disassemble the heads, do the CNC machining, re-assemble the heads, re-assemble the longblock, re-install the engine, go through some break-in period, then re-tune the car without making any other changes to the setup.

That's a lot of time and money that I personally can't afford and wouldn't expect a customer to want to spend either. Luckily, however, we do have a customer car right now that will be doing this. We built his hybrid when we first opened the shop and used thicker head gaskets to bring the CR down. He has now opted to go through with the CNC work without changing anything else on the setup. This will give us a great before/after comparison and I'll definitely be posting the results. You do have to remember, however, that even this comparison will not be perfect. The tunes will be done during different parts of the year, in different weather conditions which can skew things a bit. It should still, however, show a clear trend.

Honestly, the idea itself is very simple and most people should be able to understand it. Simply put, we are trying to replicate a complete STI engine... that's the end goal. With this in mind, we modeled our program using a stock STI head to simply replicate the stock STI combustion chamber in each head. The end result is an engine that performs very similarly to a complete EJ257. Pretty simple overall... the only tricks were in the actual execution.

Thanks
-- Ed