Need help from the flathead gurus...? Valve clearance issue

40cpe said:
I wonder if Joe says they "must be used" simply because of the difference in length or if there is something more unique about them.
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There are also comments about the inside radius not being compatible with some springs. But again I wouldn't even dream of using them, so really have no experience with them nor have I ever researched much on them. Most references I have seen state something like used on stock rebuilds only and not used on high performance applications.

Just started a separate thread on this topic. It will be interesting to see if anyone else has any experience with this.
 
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40cpe said:
This is my spring tester. Set the nut on the post at your installed height, put the metal tab on top of the spring and compress. When your ANALOG ohm meter shows contact observe the bathroom scale. Adjust the nut to see how shims affect the pressure.

PS, sorry about the picture orientation
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It's an interesting idea. Have you ever had anybody test your results? I just picked up a Proform spring tester with built in spring mic from Summit for a whopping $100. In the interest of putting it through it's paces, I'd be happy to measure a new Egge stock flathead spring and/or a new Isky 185G spring at any height you request for your own comparative purposes. I mean, I'm sure the bathroom scale method is "close enough", but, I figured I'd offer just in case you were curious.
 
My bathroom scales seem ridiculously high every time I stand on them. I'm sure they must be faulty.

Mart.
 
Casey, I just saw this thread, and a page or so back, you said you couldn't find anyone with a NOS set of stock lifters to measure. I have a set on the shelf up at my shop. I could put a calipers on them if you still would like that measurement. It sounds like you are beyond that now, but let me know.
 
tubman said:
Casey, I just saw this thread, and a page or so back, you said you couldn't find anyone with a NOS set of stock lifters to measure. I have a set on the shelf up at my shop. I could put a calipers on them if you still would like that measurement. It sounds like you are beyond that now, but let me know.
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I am past this, though, if you're interested in letting those lifters go, and they're ALL 1.750", I might be interested.

It seems that there are two lengths of the common hollow-bodied ford cam followers. Early seem to be 1.720" and late seem to be 1.750". I'm not exactly sure where in production the change occurred.
 
The new for 52 that begun in 51 was the largest valve train change since the 59 series production ended in 1948. A new cam, valves, springs, & rotator type retainers in this change. The tappet followers 8BA-6500-A changed to the EAB-6500-A so there was a difference.

Now days the EAB stuff is still a bit harder to source so most folks ditch it and change back to the 8BA stuff when major replacements are needed. It does lead to some confusion though when parts are mixed & matched.
 
Well, I'm really reluctant to use heavy adjustable lifters. And the lower keeper groove on the Chevy valve makes fitting lash caps a bit of an issue. If anybody has a set of NOS EAB-6500-A valve tappets (lifters), I'd love to buy them. Need a full set of 16, and would need you to verify that they are all in fact 1.750" tall.
 
Having read this thread all the way through, I feel really bad for you. There is a lot of good advice above, but the number of respondents surely must be getting confusing. The problem I see with the respondents, is the degree of complexity you are being exposed to. The flathead is a very forgiving motor that will tolerate a very broad range of technology. Today it seems to be the case, many are trying to make a silk purse out of a sows ear. Throwing a lot of money into a flathead can be an exercise in futility, only making one feel high tech. The performance increase is only realized with extreme expense. Running 4 ring pistons is fine, but some will argue they rob horsepower. Are you really concerned about maybe loosing 2 horses in an 100 HP motor. Light piston pins? come on really, who cares. Sleeved guides, good bet with alcohol fuels, but necessary, no. Adjustable lifters, buy a good set and forget about it. High flow valves, if your not running a blower, forget it. There are several other examples, but if you start chasing them all your just throwing your money away. You already have, $5000 and still having an incomplete solution is atrocious. I suggest, and I'm not trying to slam anyone, you work with an old timer who does a lot of builds, but is not a "performance guru" but builds nice reliable and affordable motors like Walt Dupont. It might be too late, Your chasing after too many opinions.
 
Alright, while I fully admit to being on a process of discovery, I just got my NOS set of 8BA-6500-A FoMoCo Valve Tappets, and it's quite obvious they have never been in a motor, but there is NO discernable convex shape to them. Is it THAT subtle!? I mean, somebody...Gary, maybe, said that when you put them end to end it becomes aparrent...well, I sure can't tell.

One of the old manuals that I saw said that they should have a 96" radius, but that flat is "ok", and to replace if concave. Am I chasing a ghost!?

Pics or it didn't happen...
 

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crazycasey said:
Alright, while I fully admit to being on a process of discovery, I just got my NOS set of 8BA-6500-A FoMoCo Valve Tappets, and it's quite obvious they have never been in a motor, but there is NO discernable convex shape to them. Is it THAT subtle!? I mean, somebody...Gary, maybe, said that when you put them end to end it becomes aparrent...well, I sure can't tell.

One of the old manuals that I saw said that they should have a 96" radius, but that flat is "ok", and to replace if concave. Am I chasing a ghost!?

Pics or it didn't happen...
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Yes, it IS that subtle. The only way to see it is to hold them up to a light. You will see light around the edges that dissappears in the middle. If you mic a new ground cam, you would see a difference in the lobe to accommodate the crown on the lifter.
 
If you figure a 96-inch radius into a circle diameter of 192 inches, that is a pretty large circle indeed. 16 feet as a matter of prospective. If you imagine a circle that large and cut a pie section of 1-inch width at the circumference, you would see that that 1-inch wide end would look to be almost a straight line to the naked eye. If you put an accurate straight edge from a machinist's square or something at least as accurate across the middle of the tappet face, I'm sure you would see a bit of daylight in the center. If not, then maybe it is flat.

There was a reason for the radius there. It makes the tappet rotate a bit so as to not wear a divot in the face during 100K miles of operation. It also helps to reduce wear in the tappet bore due to a reduction of side forces caused by the pressure of the cam lobe forcing it to move. I read a statement from Barney Navarro about what happened when they tried to use smaller diameter mushroom tappets from a 6-banger in a flathead V8 back in the day. He mentioned that the wear on the sleeves they put in the tappet bores to reduce the diameter was too rapid so they went back to regular tappets. I think he tried locked in roller tappets too and they just caused even more wear.

The old Tobin ARP tappet facing machines could be set for the desired radius but most all manufacturers were near a 100-inch radius, give or take a small amount, back then.
 
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Hi Casey, they must have that radius to work correctly, without a doubt. That very slight radius helps the lifters to turn and keep a constant new oil supply on the lobe! They also (help) keep the cam positioned where it belongs, the cam lobes are normally ground with a slight taper also.

Thanks, Gary in N.Y.

P.S. Hold 2 lifters against each other, the surfaces that ride on the lobes, and they should "rock" ever so slightly. See the shot here.
 

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In regards to your Tappets photo, I have seen, so called NOS that were flat. Can't explain that. Still not right.
 
Russ/40 said:
Yes, it IS that subtle...
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rotorwrench said:
If you figure a 96-inch radius...
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GOSFAST said:
Hi Casey, they must have that radius to work correctly, without a doubt...
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Well, I must have just about the world's worst luck. I cleaned the dried Cosmoline off these lifters, held them together, and tried to rock them back and forth...held them up to the brightest light in my shop, and they are DEAD flat. I'm sure they're true NOS, but maybe they just weren't made right. I DID notice that there is no swirl on the bottom. There are the slightest machine marks in a very slight arc across the lifter face moving in one direction. Picture for reference. This is getting frustrating.
 

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Hold the lifters together and try to insert a piece of .001" feeler gauge at the edge.It will confirm flat or not. "Pete" should chime in as he is resident cam guru.

R
 
Ronnie said:
Hold the lifters together and try to insert a piece of .001" feeler gauge at the edge.It will confirm flat or not. "Pete" should chime in as he is resident cam guru.

R
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My thinnest feeler gauge is 0.0015" but she won't fit. These suckers are flat. In fact, they may even be slightly concave, because they seem to stick together ever so slightly (suction!?) when sticking them end to end. I may as well just start lighting $100 bills on fire at this point. Haha!
 
So, I plugged some numbers into an arc calculator. The stock ford tappet is ground on a 96" radius. With a width of only 1", that creates an arc that is 0.0013" tall in the center. Stick two 0.0013" tall arcs together and you've got over 0.0025" at the edges, so my 0.0015" feeler gauge should have definitely fit. I sure would appreciate if somebody with more knowledge than myself would confirm my thinking.

Elgin cams is in my town. He'll resurface tappets to my desired radius. Bummer part is, last I heard he charges $8 each. So I'll be about $250 total into these solid hollow tappets.
 
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a lot of NOS parts are still on the shelf for a reason - a lot of them are 2nds at best and they just aren't right hence the reason they have never been used and still sitting on a shelf but someone doesn't want to get rid of them for whatever reason but then these parts end up on the market as NOS and the rest is history...

You seem to be getting hung up on little details and making what should be a simple build incredibly complicated. As someone up thread said find an old timer who has built lots of these engines to work with and get them to build yours.
 
Here's a quote from Pete from 1/10/16 thread titled Ford lifters on an iskenderian cam.

"NOS lifters are not recommended.
They are ground flat.
Ford decided it was cheaper to live with the failures than to install the machinery to do them right."

I've put this here as there's lots of talk about the 96" radius face profile on original and NOS lifters, I've not seen a NOS lifter that wasn't flat, can't say I've had masses of them through my hands, but a reasonable amount. This observation does tally with Pete's comment quoted above. So folk must have been using flat face lifters for 60 years plus.

I can't comment on the new Johnson lifters Gary sells, I've not had them in my hand but from his pics and posts, they are not flat. The 96" radius of his lifter faces are most definitely the best way to go, can't argue with the science. The cam lobes should be ground with a slight taper to get the full rotating benefit conducive to long life.

I'm not saying that the radius is not necessary, it is ideally perfect. Just saying that flat lifters have been used for years in engines rebuilt using genuine NOS Ford lifters.

Any one else had experience with stock NOS flat lifters? I'm surprised this hasn't been mentioned in this post.
Martin.
 
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