Monty, seems that the passages alone would create a great deal of turbulence, directing the fuel charge into the plug and swirling the whole thing up, if I had an extra head buttom I'd be willing to try it out in steps,grooves,channels,passages and see which one has a better effect.

Did u read how his effects on two strokes weren't exactly the best , I have tried many things but I haven't tried drilling through to make passages such as he describes .

I will do some playing

That was a longer read than I figured it would be. Then again I started doing google searches for more info and some pics. In theory, I would think the grooves should work great. I figure the trick is getting them the right size and then getting the compression on the engine right. Let us all know what you guys find out.

Yes I did, but I feel there always room for improvement, like i said on the PM, I'd like to try,tinkering is in my blood, I wrench on cars for a living and I'm always trying to improve on things.

Bumping for dyno tests

it's coming...but I have been too busy working on customers engines to stop and test it...I am hoping I can get something done on it this week... !

No hurry, i was just bumping it back to the first page so it wasn't forgotten.

No problem ! I have been pretty busy with engines this last week, and looking to be busy this week coming..However I have a brand new freshly broken in OFNA JL .21 that I will test the button mod on. I just need to finish a few engines first before I can take time to play ! LOL... I am pretty curious to see the results, accroding to the XRC dyno testing it does improve power

I'd think to do this properly, you'd want to be able to generate a consistent profile with repeatability.

Properly setup on an index table with the right tool would be ideal here. Not sure how practical that is though (small scale tuners with limited development budgets).



Interested as well Neal. Keep us posted. My xz-b 25 needs some love


Thanks,
Eric.

Well I did some testing with this mod



From results so far the engine loses power in the upper end

First the engine was tested with a normal button, then the engine was tested with the grooved head button... then I decided to raise compression slightly to compensate for the cuts...... The engine did gain back some of the lost power with the raised compression, but still not as good as the stock head button

yellow is stock head button
red is cut head button on its own
Blue is mod head button plus reduction of head clearance 0.05 mm

wow not liken those numbers Neal. thanks for posting your results.

maximo, do you mind posting some pictures of the button mod?

Realy weird. As mentioned before me and my friend did notice a better midrange and my friend with his 23cc bigscale also did notice a better milage what I didn't. The milage could be better detected on a 30 minites driving on one tank as I have problems to reach 5 minutes.

this is exactly what I did for my test....

I was disappointed to see it lose power, I was hoping to find a new little trick to add a little more power...But the power drop was very apparent, I made multiple passes on the dyno and tried retuning the engine to see if the tune had changed...but no matter what I did the power was down...only after I raised the compression did the power recover some...but I think with the raised compression and the normal button power would have been even better......On my modified B5 this mod hurt power, there is no question...maybe on another engine the results would be different IDK.... Sorry to disappoint you guys, I tried my best to make it work !