Results of milling iron heads.

[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.

[scooder]

Damn good stuff right there. Always good to here actual seat of the pants results.
Increased flow as we know helps up top, and cutting heads drops the breathing ability, again we know that. But cutting heads also ups the compression ratio, which helps down the bottom, and this is where you feel it in real world driving on the road.
Like what you did with the flap wheel, it removes a sort of sharp edge left over from the cutting.
Are the heads also C59A? Are these already slightly higher compression ratio than the US 59A heads? I don't have my head chart with me. Did you CC the heads pre and post cut? Be good to know the numbers ( for me )
last thing the Weiand heads, I think these were actually quite low compression when compared to Offy 400's and down, and Edelbrock heads. I've heard reports in the past from folk who put them on stock size engines and we're disappointed with the result, replaced them with offy 400's and loved them. To clarify I'm talking stock size street driven flatheads with stock or mild cam, two carbs and No porting. Not high winding large cube silly cam race engines.
"raped ape" I like that a lot, sounds fast.
Martin.

[Bassman/NZ]

Originally Posted by scooder

Damn good stuff right there. Always good to here actual seat of the pants results.
Increased flow as we know helps up top, and cutting heads drops the breathing ability, again we know that. But cutting heads also ups the compression ratio, which helps down the bottom, and this is where you feel it in real world driving on the road.
Like what you did with the flap wheel, it removes a sort of sharp edge left over from the cutting.
Are the heads also C59A? Are these already slightly higher compression ratio than the US 59A heads? I don't have my head chart with me. Did you CC the heads pre and post cut? Be good to know the numbers ( for me )
last thing the Weiand heads, I think these were actually quite low compression when compared to Offy 400's and down, and Edelbrock heads. I've heard reports in the past from folk who put them on stock size engines and we're disappointed with the result, replaced them with offy 400's and loved them. To clarify I'm talking stock size street driven flatheads with stock or mild cam, two carbs and No porting. Not high winding large cube silly cam race engines.
"raped ape" I like that a lot, sounds fast.
Martin.

The heads are C7RA-A which seem to be what comes on the Canadian 59As. I did not cc them first unfortunately. The edge of the chamber after cutting was about 5/16" in from the gasket line, and when I tried them like that, the edge kissed the piston, so I shaped the dome back out to the gasket line.

[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?

[Kahuna]

I am also a big believer in the C7RA heads. The combustion chamber seems to be much better shaped than the aftermarket hi-compression stuff available.
Just my opinion

[T Scott]

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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?

Charlie Yapp had an article in Secrets of Speed about a year and a half ago about a guy in India who was grooving head combustion chambers with supposedly positive results. These were later model overhead valve heads but as I remember some of the feedback was that a lot of guys were itchy to try it on their early Fords, both bangers and V8's. Maybe a call to Charlie would be worthwhile to see where that whole thing went.

[Talkwrench]

Good to hear. I suppose it would be the same for my little 37 21 stud? chamber size similar?

[Ol' Ron]

>050" is quite a bit, I just took .040" off a set of EAB heads and had to do the sane thing with the edge. I really don't think it raises the CR all that muck, mabe 1/2 point at most. What it does is create a very high turbulent AF mixture slamed right into the spark plug at just the right time. This will also improve fuel economy in cruise. Now get you AF right, and timing right and you'll understand what John, Richard and I have been talking about for the past few years. It's called Tuning.

[scooder]

Originally Posted by Talkwrench

Good to hear. I suppose it would be the same for my little 37 21 stud? chamber size similar?

Yep! Cutting heads a decent amount (.040-.050 or as much as you dare) will give you higher compression ratio and a tighter combustion chamber, all good.
Just make sure nothing touches.
Martin.

[49fordv8f4]

I do know that if you mill .100 off '49-'53 Merc heads and run them on an 8BA with a '52-'53 Ford cam you will have to use two gaskets on each spark plug to keep it running . But, that engine would also run 60 mph easy in a '47 COE with a 16' bed and a two speed axle. I don't really know if milling the heads made much difference other than causing the valves to mash the spark plugs closed, but the engine did run good. I modified the late model cam so I could use a '42 crab distributor. The engine was bored .040 but otherwise stock. I always felt the cam probably helped as much as anything.
Mark

[Walt Dupont--Me.]

The 52-53 EAB cam is a good cam.

[Talkwrench]

Thanks Scooder. Is it wise to work off the chamber size? Meaning can it be taken that if it CC's at what a stock head should be it would then be safe to mill OR can there be other variables?

[Bassman/NZ]

I arrived at the 50thou by using the tinfoil ball system. The tinfoil spec'd out at 95thou. Ol Ron and JWL recommended a 45thou quench space, so there's the 50thou. There was heaps of space above the valve heads, so that did not enter into the equation.

[scooder]

Originally Posted by Talkwrench

Thanks Scooder. Is it wise to work off the chamber size? Meaning can it be taken that if it CC's at what a stock head should be it would then be safe to mill OR can there be other variables?

I don't fully understand your question. But I feel you may be over thinking this. Stock engine with stock heads, a 0.050" cut won't get you in to trouble. Just make sure of your clearances. I feel an more than 0.055"-0.060" the head sealing face may be gettin to thin, if you look at them the castings arnt very thick.
I would be cool if you did cc them before and after, and let us know the figures and type of head. I do like good reference numbers.
Martin.

[blucar]

It was over fifty years ago the last time that the 59 AB engine in my '36 was rebuilt. We discarded the Offy heads that had been on the engine since '54 because they were badly eroded. The machinist that did the work was very heavy into building engines for the stock car racer's, therefore he wanted longevity..
I don't recall how much the 59AB heads were shaved, I do recall that the heads were modified, being "domed and flycut".. I do know that the object was to get the compression ratio up to about 9. to 1.. The engine is over-bored .060, four ring pistons, Weber F-1 cam. The carbs are two 97's on a Offy Super manifold..
The engine runs very nicely on 89 octane fuel..

[scooder]

Still going strong after fifty years, I'd say he got the longevity right. Sounds like a nice little engine.
Martin.

[Ol' Ron]

don't think you can get any where near 9:1 CR with stock 59 a heads with that small an engine. The transfer area is much too big. The best heads for that engine would be the 81A heads, but 8;1 would still be difficult. However, a tight piston to heaad clearance can do wonders.

[34s4ever]

Glad I saw this thread!..I was just thinking about doing this to the 21 stud motor in my car rather than buying a set of repop Eddie Myer heads..After discussing it with my machinist we decided to start with a 35 thou cut but I'll try the tin foil measurement first to see what clearance I have..CCing the chamber too!

[scooder]

Originally Posted by 34s4ever

Glad I saw this thread!..I was just thinking about doing this to the 21 stud motor in my car rather than buying a set of repop Eddie Myer heads..After discussing it with my machinist we decided to start with a 35 thou cut but I'll try the tin foil measurement first to see what clearance I have..CCing the chamber too!

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.

[Brian]

34s4ever, Those repop Eddie Meyers perform far better than any stock Ford head; cast iron or aluminum. They have a different shaped combustion chamber and relocated spark plugs.

[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.

[Ross F-1]

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. ...

I measured clearance to my stock-style pistons (I believe they are Sealed Power) and EAB heads using clay. I don't believe my heads have ever been cut. I'd have to cut quite a bit more than .010 - .030", see below. The valve clearances are after rotating the engine thru two revs.

[Ol' Ron]

I don't trust the clay method any more. I use the aluminum ball method. Lwss messy and more accurate. Take a small square od aluminum, roll it up into a dmall loose ball, place a dab of grease on the spot to check and you'll get a very accurate measurement. I couldnt read your numbers. looks like .125??. Sounds like Merc pistons in your engines

[Ross F-1]

They're stock-type and for Ford. Yes, 0.090" on the passenger side and 0.125" on the driver's side with used gaskets torqued down. I'll try the aluminum foil next time it's out. I ended up not getting them cut because it appeared to need such a huge cut.

[Bassman/NZ]

Originally Posted by Ross F-1

They're stock-type and for Ford. Yes, 0.090" on the passenger side and 0.125" on the driver's side with used gaskets torqued down. I'll try the aluminum foil next time it's out. I ended up not getting them cut because it appeared to need such a huge cut.

Mine were 0.095" I think from memory. I took 0.050" off them, no problem.

[scooder]

Originally Posted by 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.

Thanks Ron,
Do the rebuilt stockers get the heads cut for your 0.040"-0.050" clearance with OEM pistons?
The reason for the questions,
I recall that it's been said that egge pistons have a higher crown. Don't know wether this is still the case. When I've measured the clearance on a Flathead with OEM pistons and stock heads, I usually get somewhere near Ross's numbers, twix 0.090"-0.120" these are numbers averaged from a few different engines, all pre end of war blocks and a couple of Pilot blocks (essentially a 1937-38 21 stud). Never measured a post war one.
What do you reckon?
Many thanks,
Martin.

[47 flatbed]

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I will never use egge pistons in a flathead again. Especially with eldebrock head the crown is so far off it will hit heads. I run Ross only street engine or a hotter flatty just what I like from prior problems to each their own. Eldebrock products are the number 1 returned merchandise at summit racing

[fryguy]

I just heard back from the maching shop in regards to having my NORS 21 stud heads milled. I had him cc the chambers prior to milling and he said they were about 81cc chambered heads. I told him I wanted to get down to about a 60-62cc chamber to get the compression about 8:1 He milled .08 off one head and .09 off the other to get me a 61cc chambered head. He told me he measured for thickness to make sure there was enough meat. He told me they had 300 thousandths thickness. Pretty thick castings

Fryguy

[flatjack9]

I wouldn't mill anything until I checked piston and valve clearance in combustion chamber.

[Ol' Ron]

WOW!! I have a similar problem right now, serves me right for not checking both heads. The .123 still bothers me, but .070-.090 is quite common. Milling the heads to increas the CR is a poor choice, because you'll probably have to have the heads re domed. I thinl ALL heads should be milled to give at least /050" piston to head clearance just to increase combustion chamber turbulence. This will improve throttle response and economy. Especially if you have to remove that much material, it will increase the CR some what. As for Egge pistons, you're right. If you don't like them for some reason then use what ever you do like. I've been using them for over 20 years and have had only a few problems which I solved one way or anothe. I consider my self an engine builder not a person that just puts everyting together and ezpects it to work. Every engine has it's own problems and application and you may have to think about what you rae doing. Ross pistons are one of the best Racing pistons on the market, but after 50 or60K miles in a street engine are pushing oil. Due to their design they must be fit Lose in the cyl. I run .005 at least because flatheads run hot and you don't want to gall a piston. I run .002" on an Eggy and the new Metric rings do the rest. IMHOP

[gwhite]

Originally Posted by T Scott

Charlie Yapp had an article in Secrets of Speed about a year and a half ago about a guy in India who was grooving head combustion chambers with supposedly positive results. These were later model overhead valve heads but as I remember some of the feedback was that a lot of guys were itchy to try it on their early Fords, both bangers and V8's. Maybe a call to Charlie would be worthwhile to see where that whole thing went.

Somender Singh is the Indian gentleman's name, although he's hardly the first to experiment with grooving combustion chambers. This photo of an unknown vintage T head popped up on the Model T Ford Club message board a couple years ago, uses the same principle;

[56markII]

I'm very curious wondering why about the methods used to measure the clearance between the cylinder head and crown of piston?? By methods balls of tin foil or clay being used. Back in the early 80's working at a John Deere dealership that sold John Deere snowmobiles I was presented the task of working on them and there were a host of problems with some of the models of Kawasaki engines used in the liquid cooled sleds and this applied to the 440 Liquid cooled used in the Liquifire sleds. Extremely temperamental starting usually when engine was warm, not cold or hot and of course bogging while trying to accelerate from idle. After having numerous blasts of $h!t from angry customers with defective toys I discovered milling the heads on a lathe was a very positive solution! I used very soft solder used for electrical soldering and bent to a 90 degree and snaked through the sparkplug hole, rotated and measured using a micrometer. Obviously if the Kamikaze 440CC survived using solder as a crush measurement a venerable Ford Flathead should survive as well? Compared to using foil or clay and then attempting to properly measure using a micrometer. Milling the Kamikaze 440 heads .010 inch did wonders and of course if another came around with possible compression problems due to mechanical failure or wear, I would recheck using solder to determine if the mod was done or not.
Now for compression results? Anybody do a compression test before and after to see what is accomplished after milling? As Ron mentioned it is not necessarily the compression but turbulence being changed as well. Compression tests will have a variance as well due to altitude with sea level being the highest but a before and after would be nice.

[56markII]

Originally Posted by Ol' Ron

WOW!! I have a similar problem right now, serves me right for not checking both heads. The .123 still bothers me, but .070-.090 is quite common. Milling the heads to increas the CR is a poor choice, because you'll probably have to have the heads re domed. I thinl ALL heads should be milled to give at least /050" piston to head clearance just to increase combustion chamber turbulence. This will improve throttle response and economy. Especially if you have to remove that much material, it will increase the CR some what. As for Egge pistons, you're right. If you don't like them for some reason then use what ever you do like. I've been using them for over 20 years and have had only a few problems which I solved one way or anothe. I consider my self an engine builder not a person that just puts everyting together and ezpects it to work. Every engine has it's own problems and application and you may have to think about what you rae doing. Ross pistons are one of the best Racing pistons on the market, but after 50 or60K miles in a street engine are pushing oil. Due to their design they must be fit Lose in the cyl. I run .005 at least because flatheads run hot and you don't want to gall a piston. I run .002" on an Eggy and the new Metric rings do the rest. IMHOP

Now with the mention of the Ross Pistons pushing oil after 50-60k miles how do the Pistons and or Metric Rings stand up for pushing oil? Thinner with less pressure against the cylinder walls reminds me of the lower friction rings used in my 1987 Mustang GT I used to have where a bit of oil consumption if it occurred was considered normal. Also the early 337 Lincoln apparently had oil consumption problems and updating with a 3 ring piston was done which surprises me because I have OEM style 4 ring Pistons without oil consumption problems. I can see an advantage of less drag using 3 ring and metric rings as well. As for oil consumption and the lifter valley oil spray deflectors I and others I know have thrown them away for extra spray up to the valves with little or no extra consumption. I can live with a slight consumption for the increase of lubrication such as valves and it is most likely the same as hollow pushrods or pressurized oil to the rocker shafts such as the FE or my 368.