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What is the purpose of angle milling heads? Reducing chamber volume is my only guess. If the intake edge is left alone do you still have to make adjustments to your intake manifold? I'm new at this, sorry for dumb questions.
 

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Angle milling heads was popular back in the seventies. Back then all that was available were basically stock production based heads. Angle milling made an improvement in the intake charge angle. Modern heads have that built in.

If you cut the deck at an angle. The intake must also be cut. When this procedure was popular a small protracter type guage was used to set both angles. The intake usually needed the end rails cut also. The head bolt holes have to be spotfaced and sometimes the holes have to be enlarged and/or redrilled at a better angle. Pushrod holes elongated with a "Louis" tool.

I haven't heard of anyone angle milling for a long while. At least since the mid eighties.
 

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Unfortunatly some of us still have customers who want their heads angle milled. :rolleyes: Then they complain why it costs so much and why the intake needs to be cut also.
 

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Angle milling while it may have improved intake line was primarily done to bump compression. By milling more on the plug side, the deepest part of the chamber, you could remove more ccs and raise the compression and not use pop up pistons that hinder the flame front.
 

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Angle milling also often necessitates a custom valve train as well as the missfits mentioned.

For any head milling, flat or angled, the intake face of the head should be milled to allow a stock intake to fit. All competetent machine shops will do this automatically when they mill the head gasket surface.

Angle milling also makes the head prone to cracking.

About the only thing we have angle milled in the last 10 years were a couple of 403 Olds engines to try to get the compression up to 9 with aftermarket pistons. I don't recommend it. Use 350 heads.
 

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Race it, Don't rice it!
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Weird...

I couldn't tell you how many heads angle milled in circle track engine shops just today.

A popular move would be Dart 200ccx64cc heads rolled over .180 then cut flat to the intake seat for 35cc [email protected]:1 on a flat top engine rule. You also need to spot face the bolt holes and correct the intake face. Exhaust side can be left alone most times. Maybe not in a street car.

You always want to use the smallest dome possible to lighten the piston so you can use less crank weight.

Dart 49cc heads are .100 closer to the deck surface and can't be rolled over that far.
 

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also promotes flow on a 23 degree head by reducing the valve angle. However with the cost I don't beleive it would be worth the money on the street.We do it when rules limit us to 23 degree heads or certain casting numbers.
 

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barnym17 said:
also promotes flow on a 23 degree head by reducing the valve angle. However with the cost I don't beleive it would be worth the money on the street.We do it when rules limit us to 23 degree heads or certain casting numbers.

deleted :thumbup:
 

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johnsongrass1 said:
Weird...

I couldn't tell you how many heads angle milled in circle track engine shops just today.

.
As Bob [email protected] implied and I agree:

There are only certain classes that require stock iron heads that need angle milling. Aftermarket heads are a better solution in the allowable classes.

Many, if not most, stock heads get prone to cracking when angle milled.

Angle milling specifically built racing heads is another matter as they have thicker decks.
 

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DaSouthWon said:
I have a lovely sister Tom and I need some work done. Trade?
Oh, boy, youbetcha!
;)

As far as angle milling goes, it's still fairly common to have it done yet today, but the availability of off the shelf parts has cut down on most of the need for it.

tom
 
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