model A and model B lifters

I don't expect that a reground cam would last as long as a nos A or B cam. Some of the surface hardness would be removed. The better cam grinders don't remove that much from the tip of the lobe and the tip of the lobe is what counts. It is usually lift that is most important to most. the amount that is removed from the heel of the cam only adds to the lift and the heel of the cam is where the adjustment begins. the heel of the cam is not under valve spring pressure. Jim Brierly, the famous cam grinder that posts here has stated that the amount of surface hardness that is removed will make little difference. I don't expect to put another 50.000 miles on any of my model A's in my lifetime anyway. I've got two reground 3/4 race Winfield grinds from Bill Stipe that are performing and holding up very good. The cam in my speedster was installed twelve years ago and the one in the roadster has been running five years so far. Ive got a model B cam that was NOS when I installed it in my speedster in the early ninties. This engine is sitting in the back corner of my shop. This engine was still running when I removed it. I just replaced it with a more powerful engine with the reground 3/4 race cam. Maybe it wasn't the cam alone that made the difference. I have used the single lock adjustable lifters with every engine that I have done except one.
 
hardtimes said:
Herm,
Thanks for explanation. Hmm, I have a NOS B cam and you are right on...as it has BLACK colored lobes. Copper color in between:).
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That doesn't sound like a NOS cam. The production era cams were forged and heat treated. The steel had a fairly high carbon content at .4%-.45%. The heat treatment provided a controlled displacement of the carbon. These were all bare steel.

"B" cams supplied by Ford later were made from billet and carburized for hardening which is essentially inducing carbon to a base metal with only about .2% carbon. This is a form of case hardening. These were copper plated everywhere except the lobe and journal surfaces. The copper protected the other areas from the surface hardening which would otherwise become brittle. These cams came originally with shiny steel lobes similar to what you would get from Bill Stipe or in the past from Harvey Crane.

Your cam still could be NOS and someone just messed with it before you got it. One sure way to tell is to put a straight edge across to journals, positioned over the tip of one lobe. If it is unused and unmolested there will only be about .001" between your lobe tip and the straight edge.
 
hardtimes said:
Herm,
Thanks for explanation. Hmm, I have a NOS B cam and you are right on...as it has BLACK colored lobes. Copper color in between:).
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Mr. Hardtimes, you can measure the 3 bearings with a Mic, and or if you have a lathe, or a friend has one, can measure the lift, or how far the Toe is from the center line of the cam, with a Dial Indicator, Then you could see if it was reground, and that would be all right also. Herm.
 
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In 1972 I worked at a place in Spokane Wa called Unit Engineering, an engine rebuild machine shop. I spent quite a bit of time on the cam grinder. Most all of the cams we ground had a taper to the lobe and the lifters were slightly parabolic on the bottom. If you held two new lifters bottom to bottom, they only contacted each other in the center. This taper of the cam lobe and "rounded" bottom of the tappet is what cause the lifter (and pushrods in ohv engines) to rotate when running. This created more of a bearing action than a wiping action We never hardened our regrinds but did tape the bearing journals with masking tape for protection and then immerse the freshly ground cam in a heated parkerizing solution for a time. This made the cam lobe turn black and take on an acid induced textured surface which would help hold oil and aid in turning the lifter. Never ground an A or T cam but assume they would be engineered the same.
 
Did anyone notice that in the diagram Marco posted (is this from Ford service bulletin?) the B-6500 length is apparently greater, but the dimensions are not correct. Were these checked against the original drawings? Are the numbers correct but just in the wrong places?
 
"Also, I've been told/informed (by cam people, in answer to my Q re reground cams) that NO ONE rehardens the surface on 'reground cams'. Anyone have an opinion whether that is TRUE?"

False.
Many cam grinder's reharden reground cams, both steel and cast iron.
For mild street grinds on steel cams such as the model A/B there is not enough material taken off to go through the original hardening which is usually.080 to .090
deep.
The black or brown finish on some cams is Parkerizing. It is not original as Marco has said.
It is however very helpful in prolonging the life of the cam.
It helps to retain oil for initial break in.
It is best applied to cast iron cams.
Steel cams do not benefit as much.

Purdy: A reground cam will last just a long as a new one if done properly.

"Been in the cam business 59 years"
 
Thanks Pete, I was really hoping that a respected cam grinder, like you would speak up on this matter. Reground cams have really been hammered to hell by two or three individuals on this forum. I'm not necessarily reffering to Herm.
 
Randy(PA) said:
Did anyone notice that in the diagram Marco posted (is this from Ford service bulletin?) the B-6500 length is apparently greater, but the dimensions are not correct. Were these checked against the original drawings? Are the numbers correct but just in the wrong places?
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Randy,
Yup noticed that the number looked to be 'out of place' for the drawings. Mabe 'transposed/reversed' :confused:
 
Kohnke Rebabbitting said:
Mr. Hardtimes, you can measure the 3 bearings with a Mic, and or if you have a lathe, or a friend has one, can measure the lift, or how far the Toe is from the center line of the cam, with a Dial Indicator, Then you could see if it was reground, and that would be all right also. Herm.
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I had a auto engine rebuilder/machinist (Dunlop) measure the bearings and lift at: 1.559 and 5/16".
 
Purdy Swoft said:
Thanks Pete, I was really hoping that a respected cam grinder, like you would speak up on this matter. Reground cams have really been hammered to hell by two or three individuals on this forum. I'm not necessarily reffering to Herm.
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Just talked to my cam grinder of 43 years, and I was all ways told it was a harding process, and he said it does some what, but very thin, but if they want it done to a deeper depth, he said they have to send them out for that. So Mr. Purdy, all the things he told me in the hour I talked to him on the phone, backed up what Pete has said. Nothing left for me to do now, but go eat my Crow. Oh, Well, they taste a little like between a Bald Eagle, and a Spotted Owl. Herm.
 
Thanks Herm, It was not my intention to try and cause you to eat crow, or discredit your posts. This thread started out with the question by Jose Cartin if he could use model A lifters with a model B cam. I answered Jose and said that model B lifters had a larger base and were also longer than model A lifters. I suggested that if he used a model B cam that he would either need to use model B lifters or adjustable lifters. I also pointed out the fact that the double lock lifters that I have seen had a smaller base. I also pointed out the danger of smaller base lifters dropping of the nose of the cam quicker and scrapeing down the side of the lobe and causeing rapid wear. This was backed up by Ford and Vince Falters site. I was only trying to give helpful advice. Undoubtabtly Jose didn't see my answer or ignored it completely and asked the same question again. Another guy came on and said that he used MODEL A lifters with B cams on his rebuilds all of the time and bumped his post to the top. Maybe he does use model A lifters, I wouldn't doubt it. Maybe in an attempt to deminish my post on the previous thread, the guy really put his foot in his mouth. He was probably meaning that he used adjustable lifters. Just because adjustable lifters are listed in the model A parts catalogs doesn't mean that they are original model A or B lifters, neither left the factory with adjustable lifters. Also not to critisize but the lifters pictured on Ford Garage are all adjustable lifters and don't reflect the difference between original model A and B lifters. Then the thread turned to cam hardness and the poor quality of reground cams and the people that really couldn't afford a good cam. I felt that I had to keep coming back time after time to defend my cams and my credability. Nothing That I said was intended to discredit anybody. Just talking model A and trying to share my experiences and give helpful advice.

Thanks Purdy.
 
hardtimes said:
I had a auto engine rebuilder/machinist (Dunlop) measure the bearings and lift at: 1.559 and 5/16".
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The hole in the block for the cam, should be 1.562-50, from Ford, or 1 and 9/16's, I Bore my cam bearings to .002-50, to ..002-90 clearance, as any thing after .002-90, you can feel up, and down movement, and any thing below .002, you will have a slight drag, so I would say your cam is New, as far as the bearings go, I am not getting what the lift was, and uniformity. thanks Herm.
 
Purdy Swoft said:
Thanks Herm, It was not my intention to try and cause you to eat crow, or discredit your posts. This thread started out with the question by Jose Cartin if he could use model A lifters with a model B cam. I answered Jose and said that model B lifters had a larger base and were also longer than model A lifters. I suggested that if he used a model B cam that he would either need to use model B lifters or adjustable lifters. I also pointed out the fact that the double lock lifters that I have seen had a smaller base. I also pointed out the danger of smaller base lifters dropping of the nose of the cam quicker and scrapeing down the side of the lobe and causeing rapid wear. This was backed up by Ford and Vince Falters site. I was only trying to give helpful advice. Undoubtabtly Jose didn't see my answer or ignored it completely and asked the same question again. Another guy came on and said that he used MODEL A lifters with B cams on his rebuilds all of the time and bumped his post to the top. Maybe he does use model A lifters, I wouldn't doubt it. Maybe in an attempt to deminish my post on the previous thread, the guy really put his foot in his mouth. He was probably meaning that he used adjustable lifters. Just because adjustable lifters are listed in the model A parts catalogs doesn't mean that they are original model A or B lifters, neither left the factory with adjustable lifters. Also not to critisize but the lifters pictured on Ford Garage are all adjustable lifters and don't reflect the difference between original model A and B lifters. Then the thread turned to cam hardness and the poor quality of reground cams and the people that really couldn't afford a good cam. I felt that I had to keep coming back time after time to defend my cams and my credability. Nothing That I said was intended to discredit anybody. Just talking model A and trying to share my experiences and give helpful advice.

Thanks Purdy.
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We all want the truth, and nothing but the truth, Herm.
 
fordgarage said:
Rather than listening to Herm's theories, I would place my money on the expert opinion of a real cam expert like Bill Stipe.

Click here to read Bill Stipe's comments on using 'A' lifters on a 'B' cam.
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Well, Falter, I don't deal in Theories like you do on your site, as in your "WOW", steel shims, and Babbitt Theories Misinformation. I was told by the guy who ground cams for us, 30 years ago, that it was a harding process, as that is a side affect, but very thin, but the main purpose, is what Pete laid out, as I had no idea's of my own in the mix.
 
Purdy Swoft said:
Another guy came on and said that he used MODEL A lifters with B cams on his rebuilds all of the time and bumped his post to the top. Maybe he does use model A lifters, I wouldn't doubt it.
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To add to the confusion, folks are comparing apples to oranges with maybe some lemons and limes thrown in!

A "B" cam is a "B" cam but once it's reground it can be almost anything regardless of what name is placed on it. To start with, the lobes are SMALLER. It's worth noting (again) that it's impossible to duplicate ALL the characteristics of any given cam lobe at a reduced size.

From my above comments is should be clear that says they use "B" cams in all their engines they must have purchased a boat load of cams from Bill Stipe or we are back to the apples and oranges syndrome.
 
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