pistons
#101
Ya know, it sucks to see this question/thread turn into this. I don't plan on wasting money, that being said after all this I am curious as hell about measuring everything for myself. I'm really not interested in taking sides on this matter but need to weigh all the options. Right now my biggest concern is to get my Indy off his ***,speak to the actual Harley tech that will be performing the labor for his recommendation, OR FIND A NEW INDY AND SHIP THEM OUT !!!!!!!!
I have ONLY spoken to the shop owner and told him what I want done,and he is not the brains behind the Harley stuff.
I have ONLY spoken to the shop owner and told him what I want done,and he is not the brains behind the Harley stuff.
#102
#103
Glidein, don't sweat it, it's simple, get new pistons, strive for "0" deck height, use a .030" head gasket with your ev27, and run the **** out of it.
Drop the jugs on without the base gaskets, pistons with no rings, and measure, then you know what thickness base gasket you need.
Drop the jugs on without the base gaskets, pistons with no rings, and measure, then you know what thickness base gasket you need.
Kit came with .045 head and I think base is .010.
But cheap enough if I decide to buy others.
#104
Big, the pistons are the heart of the engine,
$200 on some new forged flattop pistons,
that will take plenty abuse,
that has the valve reliefs, (with room for lifter pump up or valve float)
perfect condition ring lands,
correct size wrist pin bores,
correct piston to wall clearance and straight cyl's with a rebore
30 years newer technology,
is $200 well spent.
The correct compression will be set with the headwork.
$200 on some new forged flattop pistons,
that will take plenty abuse,
that has the valve reliefs, (with room for lifter pump up or valve float)
perfect condition ring lands,
correct size wrist pin bores,
correct piston to wall clearance and straight cyl's with a rebore
30 years newer technology,
is $200 well spent.
The correct compression will be set with the headwork.
#105
You can measure deck with the old pistons, compare compression height(from wrist pin hole to the top of pistons) of the new and old pistons, and get the base gasket surfaces cut to suit,
they should get a skim cut anyway to square them so you won't have base gasket leaks.
Say if you cut the base to get .010" out the hole with a .010" base gasket, your .045" head gasket will give you .035" squish, a little less when gaskets compress, close enough, use the gaskets you have.
#106
Just got to see what combo will give you the squish your looking for.
You can measure deck with the old pistons, compare compression height(from wrist pin hole to the top of pistons) of the new and old pistons, and get the base gasket surfaces cut to suit,
they should get a skim cut anyway to square them so you won't have base gasket leaks.
Say if you cut the base to get .010" out the hole with a .010" base gasket, your .045" head gasket will give you .035" squish, a little less when gaskets compress, close enough, use the gaskets you have.
You can measure deck with the old pistons, compare compression height(from wrist pin hole to the top of pistons) of the new and old pistons, and get the base gasket surfaces cut to suit,
they should get a skim cut anyway to square them so you won't have base gasket leaks.
Say if you cut the base to get .010" out the hole with a .010" base gasket, your .045" head gasket will give you .035" squish, a little less when gaskets compress, close enough, use the gaskets you have.
#107
Just got to see what combo will give you the squish your looking for.
You can measure deck with the old pistons, compare compression height(from wrist pin hole to the top of pistons) of the new and old pistons, and get the base gasket surfaces cut to suit,
they should get a skim cut anyway to square them so you won't have base gasket leaks.
Say if you cut the base to get .010" out the hole with a .010" base gasket, your .045" head gasket will give you .035" squish, a little less when gaskets compress, close enough, use the gaskets you have.
You can measure deck with the old pistons, compare compression height(from wrist pin hole to the top of pistons) of the new and old pistons, and get the base gasket surfaces cut to suit,
they should get a skim cut anyway to square them so you won't have base gasket leaks.
Say if you cut the base to get .010" out the hole with a .010" base gasket, your .045" head gasket will give you .035" squish, a little less when gaskets compress, close enough, use the gaskets you have.
while i do not agree with his cheap idea about just swapping the pistons as a drop in with the std bore , its his money and time and they Might seat with new rings but probably not -- as you very well know the cylinders on an evo have a memory and over all the heat cycles this engine has had in 30 years its no longer round when torqued in place with different material top and bottom cylinder gaskets, so the new parts in an old environment has been tryed and shown it does not work - you would never do that and forged would be even worse as it is even more loose a fit
and we do not bore and hone the new stuff to the leaded gas spec harley never changed in the book
#108
John, I'm not sure why you're not addressing me with your post, but whatever... so to translate what your trying to tell me in a no beat around the bush language is.......if I but new pistons they should be cast, honing the cylinder is not good enough, I must bore them out over size, skim the bottom of the cylinder also.
Am I understanding ??
Am I understanding ??
#109
#110
Very misled by this forum into thinking an ev27 was a bolt in cam. Far from it !!!!! Need to boost compression because that's what that cam needs, thinner head gaskets, high compression pistons, skim cylinders, skim heads !!!!
Unless John talks me out of it, I may just buy a stock cam,Molly rings, hone and go. Of course heads are still being refreshed.