Results of milling iron heads.

[scooder]

Right, is not the yearbook that I thunk it was, it's Roger Huntington's How to hop up Ford and Mercury V8 engines.
It states 0.060 cut for dome type without other changes. 0.090 needs redoming, upto 0.125 with dome and flycut for valves!
For flat top pistons. 0.090 without other changes upto 0.125 with valve flycuts!
Sounds like a very Big cut to me, but he states this won't seriously weaken them! I'm not sure about that, but if I had a spare complete engine and heads here, I would play, and see how far you can go.
It also states "You can't cut. 0.100 of a stocker and expect it to out pull an Edelbrock"
These numbers are put here for reference and as a quote from a contemporary publication. If you decide to have a go, it's on your nickel.
I would, but I leave it up to you.
The Eddie Mayer heads you speak of, what chamber shape do they have? I know some were cast with a Navarro chamber, and some aren't?
Martin.

[Blownflatheaddeuce]

BTT....

Im looking to to exactly this on my '37 21 stud in my roadster and am wondering how much to tale off for a decent bump in the CR.

34S4EVER - can you update us with what you have found ?

BFD

[blucar]

Originally Posted by scooder

Is yours using flat top pistons or dome? Got an early 50's hotrod yearbook here with an article on cutting heads in this it states, for dome top 0.050" cut. With no need to dome or flycut for valve clearance, but on flat top type you can cut 0.080-0.090" and get 8:1. I can double check if you want.
Martin.

I don't recall what pistons are in my engine, I do recall that they are four ring. The piston that broke in '61 was a three ring, as it turned out they were not the Jahns pistons I paid for, they were brand X that the original builder of the engine substituted..
I talked to H&H in the LA area last year about freshening the engine up, it has not been ran in several years.. The last time the engine ran I turned it off, then pored Marvel Mystery oil down the carbs until they were full.. As an added precaution I loosened each spark plug, if MMO seeped out I re-tightened the plug, if MMO did not come out I removed the plug and filled the cylinder with MMO...

[Zaemo]

I needed to have .019" taken off my Weiand Cheater Heads during surfacing. I found this milling chart in an old mag (R&C?). As it turns out, it didn't do too much.

Z

[flatjack9]

Originally Posted by Blownflatheaddeuce

BTT....

Im looking to to exactly this on my '37 21 stud in my roadster and am wondering how much to tale off for a decent bump in the CR.

34S4EVER - can you update us with what you have found ?

BFD

No one can tell you how much to take off without you checking the existing clearance. Just too many variables.

[junk yard kid]

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Originally Posted by keith oh

A while back there was a lot of talk about "great results"grooving heads of other than Ford Flatheads. Has anybody had experience grooving Ford heads?

Ive wanted to try this. Ive read up on it a bit and it seems that it would help a flathead motor.

[scooder]

Originally Posted by Zaemo

I needed to have .019" taken off my Weiand Cheater Heads during surfacing. I found this milling chart in an old mag (R&C?). As it turns out, it didn't do too much.

Z

Bare in mind that the stock heads rarely come anywhere close to giving the compression ratios Ford listed as stock compression ratio.
I have cc'd a bunch of 8BA heads and a few 81A heads, should be 6.7 ish:1 and 6.2 ish:1 respectively. They all cc'd at 80cc give or take a cc. I'm not saying that all heads measure as thus, but these ones did, Would be lucky to get 6:1 on a 239ci flathead. This is why it's important to measure yours and check your clearance. Are all the pistons ever made for the flathead made with the same spec dome? Not a chance.
Martin.

[34s4ever]

Originally Posted by Blownflatheaddeuce

BTT....

Im looking to to exactly this on my '37 21 stud in my roadster and am wondering how much to tale off for a decent bump in the CR.

34S4EVER - can you update us with what you have found ?

BFD

I'll update my findings as soon as I get the heads off my 21 stud..The Eddie Myers should be better than the stock heads but I'd like to try this first before I lay out 1K for the EM heads..Its only a set of head gaskets and the machining to see how well this works..Also I have another sapre set of stock heads just in case it turns out bad..

[34s4ever]

On a side note:Is there any truth to what I've read about early to 59AB heads having different cc's depending on which side of the motor the head is on??The article said that one head has slightly smaller combustion chambers(2 cc's) to compensate for crank offset??

[Bassman/NZ]

Originally Posted by flatjack9

No one can tell you how much to take off without you checking the existing clearance. Just too many variables.

This is gospel. Most heads have been cut at some point in their life.

[Ol' Ron]

The Copper big bore gaskets have 14cc volumn at a compressed thickness of around .060". I have a .050" shim gasket and if I can find time I'll try and measure the volume.

[scooder]

Originally Posted by 34s4ever

On a side note:Is there any truth to what I've read about early to 59AB heads having different cc's depending on which side of the motor the head is on??The article said that one head has slightly smaller combustion chambers(2 cc's) to c
ompensate for crank offset??

The pre 59A heads are different side to side. The 59A And later are the same each side. I'm talking combustion chamber size, 8BA are obviously handed.
It's the valve angle that's different on the early heads. The crank offset is the same on all flatheads I believe.
Martin.

[fryguy]

I want to shave a set of stock 37 Cast Iron heads for my 21 stud flatty. I have a guys who has a couple NOS sets of the 37 cast iron heads sitting on a shelf. He's basically giving them away. I was going to pick up a few sets to play with. Based on Ford numbers, the stock Ford Cast Iron heads for the 77 Series motor(1937) was a 7.5 to one. The 81a series heads are listed as 6.125 to 1 Hopefully these are the 77 series heads.
I picked up an NOS Lucas distributor for the 21 stud motor as well. It was an English staple as they suppossedly ran the 21 stud motors in a lot of military vehicles into the 50's. It has a lot more adjustment for advancing and retarding the timing than the stock divers bell. They were supposedly sold in the states in surplus stores as a Speed upgrade item. I am thinking of picking up a Thickstun PM7 intake that a buddy is currently running. Not sure if that intake is more hype than actual performance

I haven't decided how much to shave off the NOS head until I pull my current heads and see what pistons I have.

I'd like to get Ol' Rons opinion on what cam would be nice for a mostly stock street motor.


Fryguy

[Ol' Ron]

After reading these posts again, I think some of youse guys have missed the point here. I only mill the head to give .050" piston to head clearance. This is usually a .010 at least to .030 at most. The new Edelbrock 74cc heads required .025 for the Ross pistons. This is not to raise compression, but to increase the turbulence in the chamber just befor the ignition goes bang. The increased turbulence insures all the Air and fuel are mixed so very little is wasted. Purely an economy modification, the fact that the engine respons better to the throttle is a gratuity. I'm now looking for .040" over the piston.

[Lawrie]

Ron ,you are right, I machined the cast iron truck heads on the 99a engine with the 4 in crank and got the piston to head clearance down to .040,that engine is sooo nice ,AND torquey,it has the stock 33/4 inlet manifold ,cam and 97 carb,
As a comparison,with the original 33 babbit 21 stud engine and towing the caravan over a range out west ,it will pull over the top of the range in top gear having floored the throttle 1/2 mile from the bottom at 35 mph, with the 99a engine in ,it would pull over the top at 50 mph.and this was only at part throttle.
Lawrie

[Walt Dupont--Me.]

A friend of mine died a few yr's at 85, he was one of the early hot dog stock car drivers, his name is in the Maine Vintage Race car hall of fame. Back in the 50's he always ran the 37 engine 21 stud, he would put the heads in a coal fired furnish, get them hot and melt 2 sticks of brassing rod in each combustion chamber, then he would mill them just to straighten them. I don't know what the com was but that little engine would scream. Walt

[Ross F-1]

Like this, Walt? On display at the NASCAR museum (the head on the left)

[scooder]

Originally Posted by Ol' Ron

After reading these posts again, I think some of youse guys have missed the point here. I only mill the head to give .050" piston to head clearance. This is usually a .010 at least to .030 at most. The new Edelbrock 74cc heads required .025 for the Ross pistons. This is not to raise compression, but to increase the turbulence in the chamber just befor the ignition goes bang. The increased turbulence insures all the Air and fuel are mixed so very little is wasted. Purely an economy modification, the fact that the engine respons better to the throttle is a gratuity. I'm now looking for .040" over the piston.

Ron, these engines you speak of, ate they using Egge pistons? I'm sure I read that's the pistons you use.
Many thanks,
Martin.

[36coupe]

Originally Posted by Bassman/NZ

After consulting Ol' Ron's and JWL's books, I measured my combustion chambers with the tin foil balls. I had 50thou taken off the heads, and realised that the dome shape in the chamber no longer matches the top of the piston. Some judicious use of a flap wheel produced a shape fairly close to that of the piston top, with a 45thou clearance. A pair of new Best gaskets and torque 'er down. Woah! they are right. This is the best bang for the buck to be done to a flattie. With an otherwise stock C59A engine, the result is amazing. The torque rocks the car considerably when the throttle is blipped, and out on the road the little AV8 goes like a raped ape. It actually goes much better than when I had the Weiand heads on it. Just thought this result may be of interest to anyone contemplating some basic mods.

Where can I find a step by step for this procedure and what are the best head gaskets to use?
I have the ca7 Canadian heads

[Ol' Ron]

Yes I use Egge pistons in most of my engines. However, the re-built stockers use OEM, if I can find them. Race engines use Ross and the 276 get Egge. I also found that Egge makes 3 5/16 oversize pistons. Their new 3 ring pistons use Metric thin rings.