Im getting the DS head ported, and other than just opening the combustion chamber diameter to match the cylinder is there anything else I need to do with the head, im staying with same sized valves. adding shim under buckets also.

 

Erb, you need to have your porter, install and port a hyphendeafenator plug, to .237!! VERY IMPORTANT!!! Then once you install the head, retard the right side exhaust valve 3*, and advance the left side 4*.

What?..............i'm serious!.......................quit looking at me like that...............................ok fine.......i'm outta here............................Viper just smiles and waves........................cuz he has no dam idea!!!!!!!![img]i/expressions/face-icon-small-happy.gif[/img]

 

whatever Viper is on tonight make mine a double![img]i/expressions/face-icon-small-smile.gif[/img]

 

Ok, I am going to try but i fear this will fall on deaf ears.............

Does your kit require you to open up the combustion chamber? If not, don't do it..........unless you intent is to lower your compression ratio even further. You will not notice any gains or losses by Yjacket's theory about the lip on the head needing to be removed to curb unnecessary combustion chamber turbulance[img]i/expressions/face-icon-small-confused.gif[/img]

Most of us with HPR730's are bolting on an unmodified head (specifically regarding combustion chamber) on the 105.5 cylinder[img]i/expressions/face-icon-small-wink.gif[/img]

If you are looking for what else you need to do, make sure you re-port your intake manifold so it exactly matches your new intake ports[img]i/expressions/face-icon-small-smile.gif[/img]

 

Nothing like a few good strong glasses of crown and coke. Makes a guy feel all funny inside[img]i/expressions/face-icon-small-happy.gif[/img]

 

Why I was asking was when open to 105mm thats 05mm 0.1969" good size jump up. I havent measured the stock head squish, just seem you would throw it on a lathe center it up and open it up a bit on the outside squish to match the bore, ill make a few phone calls on monday.

 

Although I am sure quish on these fourstrokes isnt as important as on the two's, I would venture to bet there is some good hp left in getting the right amount of squish, and squish taper correct. The only thing that would worry me, is if you decided later to go back to stock bore, or sell the head to someone who was a stock bore. It would leave an area above the stock gasket. I dont think it would cause much of an issue with the copper gaskets, but maybe a stock type. I dont know, just speculating.

 

Thats why I will have an extra stock cylinder and an extra stock head [img]i/expressions/face-icon-small-smile.gif[/img]