I can not tell. It is still to cold outside to spend a day at the track. To me I know it will not add something I need but the guy who has them now is going for the win this year and so everything will be tested.

looking forward to hearing about results. I might purchase one just so I can compile my own data.

Nice work. We did do similar with the SX15 back in the 90s but we were porting the backplate right back to the 70s. I believe Leonardo Garofali from SG fame was the first to do it. Not so refined as it is now. Back then, we just filled the back of the plate with metal filler and grinded 2 ports directing into the face of the plate with machine bits

Yesterday and today 2 engines did get a one on one test with these backplates. Yesterday I heard of the 1st engine that it made a noticeable difference on a better low-mid range and lowered the temp of the engine. I think that would indicate that the flow over the side ports is better giving more fuel and so more cooling closer to the exhaust..

Today I was at the test of a 2nd engine on another track than yesterday. After the change of the backplate it was noticeable that the engine did drop less rpm going through a full throttle corner.


(Running the backplate and several other mods)

So, ultimately you changed crankcase volume. I think it will create more harm than gain. But worth to try, even if it goes against Mother-nature LOL