Stock /6 head cc

[6pakattack]

Anyone by chance happen to know what the stock cc on their head is ?? My machine shop isn't equiped to check it,and want to get a rough idea what I need to shave off to get my compression #'s where I want !!Any assistance would be greatly appreciated !!

 

[805moparkid]

first off if your shop isn't equip to do cc'ing you need a new shop...

all you need is a spark lug in the hole

a CD with grease on it

and a ml syringe...

but stock they are around 52-58 if i remember...

from 54cc a .110 mill makes 44's chambers

 

[puregts]

Given the opportunity, I mean, if the whole things in the shop, wouldn't milling the block be an easier thing as the pistons sit sooooo far down in the hole to begin with? Isn't the deck much thicker than the head surface? Either way you're looking at a push rod problem beyond a certain point.
Also, I use medical syringes of the large caliber sizes (50cc and 100cc) to do measuring with as glass around the shop doesn't do so well. A piece of plexiglass scrap big enough to cover the chamber with, a vent hole and fill hole, a little grease around the chamber area to seal it and tilt it plug side down slightly and you're off and running. Each chamber will be different and with the machining process you can see if the block was angle cut and the same for the heads. On a V8 you can even swap sides to get a better balance on the engine to correct for the offset cutting.

 

[Bill Dedman]

Anyone by chance happen to know what the stock cc on their head is ?? My machine shop isn't equiped to check it,and want to get a rough idea what I need to shave off to get my compression #'s where I want !!Any assistance would be greatly appreciated !!

Consider this: If you think you will EVER use that block in a forced induction application, don't mill it. Mill the head, instead. You can't put that material back (on the block) once it's gone.

If you get the normally-aspirated version of that engine running well, and it's still only going low 14's, you may decide to give it some help in the way of boost from a ProCharger or a turbo. If you've milled the block, you won't have as easy time of it as it will, if all you have to change is the head to get the desired lower compression ratio.

Lots easier to change a head than a block...


Just sayin'...

My combustion chambers were all between 53 and 54 cc's, and the head had never been milled, to the best of my investigative skills...

With an un-milled block and Wiseco pistons (.157" down in the hole) that yielded a compression ratio of 9:1, true compression, measured with a burette.

Hope this helps...:yawinkle:

 

[Darter6]

FYI, Didn't do a before but after a .100 cut on a 67 head the cc's were at 44 at the largest chamber. A little grinding on the other 5 was done to match. I'm sure each casting will have a +/- variable.

 

[805moparkid]

Given the opportunity, I mean, if the whole things in the shop, wouldn't milling the block be an easier thing as the pistons sit sooooo far down in the hole to begin with? Isn't the deck much thicker than the head surface? Either way you're looking at a push rod problem beyond a certain point.

as for the surfaces being different thicknesses i dont know... i would have to check on a virgin motor...

and yes its better to do the block so you can get some resemblance of quench...

and lastly you need new pushrods after milling about .150 off the mating surfaces... the adjusters will take up that much...

 

[cudamark]

Can't you just the proper pistons? That way you wouldn't have to cut either the head or the block and you wouldn't have to worry or mess around with rocker/pushrod geometry.

 

[6pakattack]

Well,Wiseco says with a 54cc chamber,I should be good for 10.6 cr !! I may just decide to leave that alone so like you say,don't have to mess with anything !!K.I.S.S.