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[ImBroke]

how long before the aftermarket comes out with a higher compression piston for the 117 drop in kit?  9.9 seems a bit soft for any decent cam, 259E included. 

[HD Street Performance]

I have three sets on the way all sold.
CP with coated skirts, 7cc dome, can be trimmed

[ImBroke]

6cc dome should be about 10.5?

[HD Street Performance]

10.95 with .030hg and 7cc.
That 259e is right at home there.

[Unbalanced]

Might check with Suburban Harley they usually Pistons for many different builds, 110, 113, 120r.    Haven't checked for 117 but couldn't hurt.

[Yorktown CVO]

Little more compression and better cam choice. My HD dealer pushes that 259E cam but i.m not impressed with it. My 255 cam has better torque numbers from what I see. 

[Yellow09SERG]

Suburban Speed does have a 9cc Mahle pistion for the 117. Been trying to find out from them the dome thickness and how much that piston dome could be milled.

[GMR-PERFORMANCE]

You cannot mill the Mahl piston , its how they make it too thin , I mean you can but you are getting under min spec on that piston.

[Unbalanced]

Steve I didn't verify or state you could or couldn't mill them or that they even carried or had them.   However you could ask John Sachs as I believe he has worked with some of their pistons in the past that Mahle produces for Suburban.


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[chicoman]

I milled my suburban speed mahle 113 pistons, been 2 years and over 10000 miles and still going strong.

[GMR-PERFORMANCE]

I was not saying one way or the other to anyone really. 

 and I have used the Suburban piston and asked Rick about it as well .. it is thin,... I mean you could maybe take off a tiny amount but nothing to get you to change the comp ratio in a huge way. Easier to run a thicker gasket..

Now I had some made by Mahle, CP and Arias and the only one that I could mill was the CP.. It has to do with the forging process .  Now running right at min spec or even under can be done but I would not want to try it with a 4032 piston. The 2618 sure .. again a shop thing to a guy in his garage ( the DIY guy to be clear)  ,  I have to stand behind it.. so we are not going to push that envelope. What I guy does on his own build is just that " what he does" and just because one guys get away with it ,  does not make it right..  a 4032 piston is brittle compared to 2618.. There is a reason that there are , specs put into place by the piston manufacture..   

Mill the head and face the intake mounting area is how we are doing it , simple as the kit comes with a piston, and its less money..

 

[johnsachs]

FWIW, I've cut down many Mahle piston domes for Ultima, and Harley engines where there's enough dome material WITHOUT any problems. (I do them in house, unlike some shops, so I have complete control). 
All CVO "wet head" builds I do using Mike Roland's 24 cams get Mahle domed pistons with material removed from the domes.(done 9 of them.. plenty material left).
John

[cvo1717]

Little more compression and better cam choice. My HD dealer pushes that 259E cam but i.m not impressed with it. My 255 cam has better torque numbers from what I see. 

I went with woods tW-8 cam 10;5;1 comp and the tq is good all over

[GMR-PERFORMANCE]

FWIW, I've cut down many Mahle piston domes for Ultima, and Harley engines where there's enough dome material WITHOUT any problems. (I do them in house, unlike some shops, so I have complete control). 
All CVO "wet head" builds I do using Mike Roland's 24 cams get Mahle domed pistons with material removed from the domes.(done 9 of them.. plenty material left).
John

Who said anything about a ultima engine . Suburban  speed has the 117& 113  dome from Mahle , made to their spec  , Mahle and Suburban said too thin so if both states the same thing ..   SO to be clear that is the piston you are milling ?? or something else CVO pop up?  ,
  Now I did get to send off a set that had been milled back to Mahle for failure 107 piston that was milled ..  We did not mill them another shop did . But hey that shop does not tune and blamed the failure on improper tune  , detonation to be specific ...  Tune was not great but no signs of ign issue from what we could tell, but auto tune so no idea what happen early on . maybe maybe not 

as for milling the piston  anyone with a mill can do it , simple measurement , If there is enough thickness then sure no issue ,  mill it , but just because it has a name brand on it does not mean its the same forging

[chicoman]

I guess then that you should not fly cut if valves touch the piston, anything can be machined within reason, taking a small amount off to lower compression will not hurt, i would rather do it that way and stay with a closer squish. Set mine at 10.2 with 93 cc and if memory is good it was only .040 taken off, left plenty of meat.