Heads milled

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sireland67

sireland67

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I picked up a few small block parts off a friend of mine.
In the parts there was two sets of "J" heads.

One set looks untouched, the other set has been milled alot, they look like close chamber heads, there was so much taken off them.
What is the easiest way to determine how much these heads were milled?
He cannot remember how much he had machined off of them.

Also I have an intake that I acquired that I know has been milled, but do not know how much, how do I measure it?
 
Get a micrometer large enough to go from the flat part of a head bolt hole to the deck surface. Compare the milled head measurement to the unmilled head. That should give you an idea.
 
Good idea, that would be easy.

What about the intake manifold?
 
sireland67 said:
Good idea, that would be easy.

What about the intake manifold?
Click to expand...

Now that you will have to simply fit on an engine with known unmilled parts to see if the bolt holes line up or not.
 
Oh crap, I guess that's what I get for picking up used speed parts cheap.
I just could not think of any way to measure the intake.
 
sireland67 said:
Oh crap, I guess that's what I get for picking up used speed parts cheap.
I just could not think of any way to measure the intake.
Click to expand...

There may be a way to do it, but stickin it on an engine is the only way I know how.
 
sireland67 said:
I picked up a few small block parts off a friend of mine.
In the parts there was two sets of "J" heads.

One set looks untouched, the other set has been milled alot, they look like close chamber heads, there was so much taken off them.
What is the easiest way to determine how much these heads were milled?
He cannot remember how much he had machined off of them.

Also I have an intake that I acquired that I know has been milled, but do not know how much, how do I measure it?
Click to expand...

RustyRatRod said:
Get a micrometer large enough to go from the flat part of a head bolt hole to the deck surface. Compare the milled head measurement to the unmilled head. That should give you an idea.
Click to expand...

I like to get plexiglass and use that on the head machined face, then drill a hole and you can "scoot" it all over the head and take measurements to compare...

Use the plexi glass as a travelling base/reference.... Measure from the top of the plastic to the head face for your datum, then move to other locations and take measurements and subtract the first measurement to find how much distance from the milled face....
 
If the chambers' open part is all gone, then I'd expect in the range of .090-.110" milled off. Let us know what you find.
 
Well I measured them this morning using a 6" caliper, looks like they have been milled .125"
Notice the casting number has actually been touched.

How much do you mill off the intake face to make them match an uncut intake, I think it is .0095 for every .010 taken off the head, just going from memory.

iLx7RH.jpg
 
Not trying to highjack but interested in this scenario myself, and this question may help the op also. I have a set of heads that have been cut probably that much. The intake side was cut also and using an uncut (to my knowledge) intake I can get the bolts to line up. What I’m curious about is how much this would affect pushrod length on a hydraulic flat tappet cam?
 
sireland67 said:
How much do you mill off the intake face to make them match an uncut intake, I think it is .0095 for every .010 taken off the head, just going from memory.
Click to expand...
LOL that IS a bunch milled off. Let us know what you find when you cc the chambers; they must be down in the mid to low 50 cc range.

The numbers above are what I recall too.
 
ktcnn94 said:
Not trying to highjack but interested in this scenario myself, and this question may help the op also. I have a set of heads that have been cut probably that much. The intake side was cut also and using an uncut (to my knowledge) intake I can get the bolts to line up. What I’m curious about is how much this would affect pushrod length on a hydraulic flat tappet cam?
Click to expand...
Nominally, the pushrods would be shortened by that same head milling amount, in order to put the lifter pistons in the approximate center of their travel. The pushrod angle would make the change at the lifter a few thousandths less but not nearly enough that you could avoid changing them out. If you put stock length pushrods in, I'd expect all of the lifter pistons to be bottomed out and all the valves to be hung open.
 
nm9stheham said:
LOL that IS a bunch milled off. Let us know what you find when you cc the chambers; they must be down in the mid to low 50 cc range.

The numbers above are what I recall too.
Click to expand...
I don’t think I am even going to use them, way too many projects going on at the moment to cc them.
 
It still has open chambers, though........after all that.
 
RustyRatRod said:
It still has open chambers, though........after all that.
Click to expand...

I know he ran them on his old duster drag car, on a stroked 318, the car ran consistent low 6's in the 1/8 30 years ago, with a little help from the blue bottle.

Now he is retired, the duster is long gone, and he just got a hemi cuda, caged, tubbed etc a week ago to play with.
 
sireland67 said:
I know he ran them on his old duster drag car, on a stroked 318, the car ran consistent low 6's in the 1/8 30 years ago, with a little help from the blue bottle.

Now he is retired, the duster is long gone, and he just got a hemi cuda, caged, tubbed etc a week ago to play with.
Click to expand...

Oh yeah, they will raise compression, no doubt. They are quench heads now, which is good. But to say they are close chamber isn't correct, because of how the spark plug side of the chamber is open. I wish Mopar had made heads like that. Check out these big block Chevy closed chamber heads for comparison.

CLOSED CHAMBER.jpg
 
sireland67 said:
Oh crap, I guess that's what I get for picking up used speed parts cheap.
I just could not think of any way to measure the intake.
Click to expand...

Well anytime you buy used there is no guarantee what you got or get, sometimes you get more than you bargained for sometimes less, good and bad.
 
At least the intake was gave to me.
 
I think the heads are good! They will certainly add some pep in the step of most any small block. Go with a zero deck height and you'll get some quench benefit. Looks like they have 2.02 valves too. You didn't do bad at all.
 
RustyRatRod said:
Oh yeah, they will raise compression, no doubt. They are quench heads now, which is good. But to say they are close chamber isn't correct, because of how the spark plug side of the chamber is open. I wish Mopar had made heads like that. Check out these big block Chevy closed chamber heads for comparison.

View attachment 1715191616
Click to expand...


Chrysler called the chamber the OP has a closed chamber. What the OP gained in power form the CR he lost (and then some) in airflow.

That's about the worst thing you can do to that chamber. I've been telling guys for years to stick the piston out of the bore like Chrysler said, rather than do that. It just doesn't work very well. Even with a 50* seat. Believe it or not, it really likes a 55* seat and a big tulip on the back of the valve.
 
yellow rose said:
Chrysler called the chamber the OP has a closed chamber. What the OP gained in power form the CR he lost (and then some) in airflow.

That's about the worst thing you can do to that chamber. I've been telling guys for years to stick the piston out of the bore like Chrysler said, rather than do that. It just doesn't work very well. Even with a 50* seat. Believe it or not, it really likes a 55* seat and a big tulip on the back of the valve.
Click to expand...

Where and when? The only closed chamber small block heads I am aware of were the 273 and some of the performance heads such as the W series and all of those were closed around the spark plug area, much like the big block Chevy heads I posted above. Show me the heads Chrysler said were closed chamber.
 
RustyRatRod said:
Where and when? The only closed chamber small block heads I am aware of were the 273 and some of the performance heads such as the W series and all of those were closed around the spark plug area, much like the big block Chevy heads I posted above. Show me the heads Chrysler said were closed chamber.
Click to expand...


Look up the W-5 head. It's a closed chamber. It doesn't need double quench to be closed chamber. Most early closed chamber heads are junk.
 
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