What ever happened to angle milling cylinder heads?

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HankRearden

HankRearden

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I remember when I was in tech school in the early 90's this was considered kind of the hot ticket for the dirt track stuff I was working on as they were limited to factory cylinder heads.
I'm guessing it isn't cost effective when aftermarket cylinder heads are available.
Is this just another hot rodding technique lost to time?
 
Years ago we ran in a class that required flat top pistons and stock heads. We built a 355 Chevy with double hump corvette heads that were angle milled one hundred thousands and had 285 psig compression. It really ran great.
 
mcodecuda said:
Years ago we ran in a class that required flat top pistons and stock heads. We built a 355 Chevy with double hump corvette heads that were angle milled one hundred thousands and had 285 psig compression. It really ran great.
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What fuel were you using?
 
Aftermarket head companies started making heads with optimal valve angles. People still do it with factory heads.
 
the influx of affordable aftermarket heads that is now easily available pretty much did it.

another factor is rising costs of machine work.
 
was asking the same question and wondered if it's been tried on a 225. it would raise both the intake and the exhaust but as mentioned entails alot of extra machine work.
 
lotta dirt tracks made rules against angle milling as a way to control cost years ago, now days most them class's running a sealed crate engine... finding pistons with valve notches for lower than stock is right costly to now!!
 
We use to offset grind cranks & use Ford pistons to make strokers too.... Inexpensive (Chinese) aftermarket parts changed the game..
 
I had a set of 440 source heads angle milled .040 from the spark plug side to bring an 8.2:1 440 up to 9.5ish :1. I think if you go much over .050-.060 the intake manifold will need to be corrected on a mill. Both shops I have worked with here in OR will angle mill however they said no cbn cutter for some reason (aka no MLS gaskets).

Angle milling is a viable option in some cases.
 
abdywgn said:
was asking the same question and wondered if it's been tried on a 225. it would raise both the intake and the exhaust but as mentioned entails alot of extra machine work.
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What would be the point?
 
abdywgn said:
was asking the same question and wondered if it's been tried on a 225. it would raise both the intake and the exhaust but as mentioned entails alot of extra machine work.
Click to expand...
Yes it has been done on a slant. Not me, but a slant racer I know did (I think) .100 on the manifold side, and .200 on the spark plug side.
 
RustyRatRod said:
Aftermarket head companies started making heads with optimal valve angles. People still do it with factory heads.
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The advantage in milling has nothing to do with valve angle. It has everything to do with reducing the size of the combustion chamber and increasing the compressio.
 
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Thats exactly what we were using.
A short time after the vortec heads were available and approved and they flowed better so angle mills heads went by the wayside.
But this always stuck with me as a worthwhile practice and I've been thinking about angle milling 360 heads for a low compression 318 instead of the usual flat .030-.040 milled off.
 
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