To let you know - John John (JJ) took
Western Canadian Championship on 85 Yamaha with Somender's 5 groove
set-up. Shaving head 10 thou out-performed 3 groove. Jet sizing way
down - performance way up. 4 stroke Honda was hole shotting 90% of
every race. Thank you very much for helping us out. Happy New Year
& best wishes to you and yours. kp / whitecourt
been slowly making the head into a mess before cleaning it up, Its rough but its serving as a test for future projects...
I had a hard time catching decent pictures of the grooves i cut but let me know what you think.
Anxiously waiting to try this out.
ryan
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Re:headworking project
Date: 2007/02/11 14:57
By: singh
Status:
Karma: 4
You need to make the grooves or call them channels a little deeper than wider almost touching the rim of the H gasket. ( can very easily over cook it too ! ) i have seen smaller grooves improve torque and subside deto & ping in 4 valve engines ! Make sure the head is flat and use only OE gaskets. Lap the valves and get the right tappet gaps. i hope the bottom end is fit to take the mods ? Do you plan to shave the head later ? If so, you will have to re-groove to get the spec's right ! The World is waiting ...... to hear from you ! sing !!!!
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Re:headworking project
Date: 2007/02/12 01:51
By: bpt323
Status:
Karma: 1
Yes, tommorow the 12th I will be finalizing the headwork with more new tools, The head will be shaved to maximum factory spec. {non interference engine} to remove minor scuffs & raise compression, new valves & guides + altered angles 15/45/75 to improove flow off of the seat.
I purposely made the grooves ahead of time, jsut not excessively deep. I figured after more chamber work & shaving of the head i'd need to refile the grooves anyhows.
as for clearance to the Headgasket the intake side has a proportionately increased squish/quench area which is why it may appear off length; when compared with the exhaust side.
Grooves should be angled inwards/upwards to the combustion roof (pentroof design) correct? I.e. should I be filing them as close to spec with the angle to meet the combustion chamber roof?
Sidenote- under a good tune the bottom end is capable of supporting 400WHP @ a ratio of 7500RPM its fairly beastly.
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Re:headworking project
Date: 2007/02/12 15:39
By: singh
Status:
Karma: 4
How ever " Big or Small " the squish area is in a combustion chamber does not hamper the channel or call it the grooves from performing their rolls of jetting a stream of turbulence towards the igniter in a varying velocity than the splat squishing normally generates at tdc. In the next phase flamefronts penetrating through the dug up channels end up attacking pockets of unburnt fuel ' cooling off ' between the squish area ! This form of penetration sets alight a larger portion of the mixture causing controlled expansions in the hot gasses. This process is proportional to the density of the mixture flowing into the cylinder.
Higher Compression ratios increase frictional heat in the mixture before ignition ! We all know dense pre-heated mixtures ignite faster ! We also know in such situations we often loose control of the events once ignition sets the process of combustion alive ! In the conventional world of combustion it is accepted, no two cycles are similar due to the chaos turbulence brings in. It is at this critical millisecond phase that the grooves bring about order in the house with the help of a whip called ~ Varied Flame Velocities ! So how Big or How Small really doesn't matter ! However " How Deep " does ? Yes they need to ......... meet the combustion chamber roof ! sing !!!
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Re:headworking project
Date: 2007/02/19 13:16
By: bpt323
Status:
Karma: 1
waiting for more tools & bits to arrive via mail service today, project will continue according
Will keep all updated on any new information
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Re:headworking project
Date: 2007/08/21 02:17
By: bpt323
Status:
Karma: 1
No advancement in this project, the seats need to be recut & the head resurfaced prior to installation. possibly new guides.
Its been in the back of my mind about grooves & the application with forced induction. i've read that the grooves should be left with the sharp edges, would this not creat possible hotspots that could lead to detonation? what are the effects of smoothing the edge of the grooves ?
Thanks to any additional input!
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Re:headworking project
Date: 2007/08/22 03:13
By: singh
Status:
Karma: 4
Hello ! After you are finished with the suggested rebuilding of the head make sure you face the head to achieve the required compression ratio. Cut the grooves to the required dimensions as shown and suggested. Once done sand the sharp edges down to give you the desired soothing profiles for mental comforts from " glowing edges". Once done post the Pix and the " after effects " out of your efforts to groove 4 valve heads ! Every one else has had no problems with deto after grooving heads ! Hope every thing else falls into place ! sing !!!
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Re:headworking project
Date: 2009/01/07 12:26
By: bpt323
Status:
Karma: 1
to update, the head was shaved, the grooves were perfected & the cylinder head was installed. initial experience, i've never been behind a car with such clean exhaust. it was remarkable. the gas mileage was equal if not better then previous (could be alotted to the raise compression ratio) Either way. some A-hole stole my camera with 2gb worth of random pictures including all of the final work prior to install.
Due to a poor cooling system (owners fault) the cylinder heat cracked through its center coolant channel rendering the cylinder head scrap metal.
end result- there was zero harm or worry even in the instance of +18psi @~9.3:1 ratio I fully plan to further groove each & every cylinder head in the future.
Thank you somender for your work & contribution
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