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-   Offroad Nitro Engine Forum (https://www.rctech.net/forum/offroad-nitro-engine-forum-157/)
-   -   Modd head button (https://www.rctech.net/forum/offroad-nitro-engine-forum/445894-modd-head-button.html)

rotarynut 10-26-2010 08:23 PM

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.

houston 10-26-2010 08:40 PM


Originally Posted by rotarynut (Post 8127331)
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 ;)

dayglo33 10-26-2010 08:41 PM

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.

rotarynut 10-28-2010 05:15 PM

THATS"S JUST GROOVY... MAN!!
 

Originally Posted by houston (Post 8127402)
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 ;)

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.

wingracer 11-03-2010 07:50 AM

Bumping for dyno tests :D

Maximo 11-03-2010 08:33 AM


Originally Posted by wingracer (Post 8160023)
Bumping for dyno tests :D


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... !

wingracer 11-04-2010 08:25 PM

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

Maximo 11-04-2010 08:42 PM


Originally Posted by wingracer (Post 8167965)
No hurry, i was just bumping it back to the first page so it wasn't forgotten. :D


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

itbvolks 11-05-2010 06:35 AM

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.

Maximo 11-13-2010 06:06 PM

Well I did some testing with this mod

http://i107.photobucket.com/albums/m...tonmodsCRE.jpg

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

rider313 11-13-2010 06:35 PM

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

RUNNINONMT 11-13-2010 06:40 PM

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

Roelof 11-14-2010 02:55 AM

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.

Maximo 11-14-2010 06:41 AM


Originally Posted by Roelof (Post 8111740)

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

Maximo 11-14-2010 07:27 AM


Originally Posted by Roelof (Post 8207330)
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.


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 !


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