[Tim Corcoran]

It doesn't say where they are made so maybe off shore

https://butlerperformance.com/i-2445...tegory:1234787

[PAUL K]

Originally Posted by dataway

That chamfer is direct from GM .. both sets of original GM lifters I have, have that chamfer. Not sure how it would play with modern cam profiles but evidently it was SOP back in the day.

Looking closely you can see the OEM GM has the most chamfer, the Melling has less, and the HLJ the least.

I guess it would depend on lobe profile as to whether the chamfer would even come into the equation?

Bigger the chamfer the better chance you have of destroying a lobe. A lazy lobe with a large chamfer is the worse case scenario. About fifteen years ago I noticed Pontiac had a new part number for RAIV lifters. I ordered a set and they were re-boxed Hy-lift 951R's. Not sure why your lifter has such a large chamfer but I doubt it's within the original GM spec.

[dataway]

Don't know what to tell you, I opened the sealed boxes myself. Original 40+ year old GM parts in GM boxes. Both sets the same.
Would be curious to see other examples of original GM lifters in this age range.

[Jay S]

Originally Posted by Formulas

Any insight as to the current SFT. offering from Comp 2900-16 Series... Actual MFG.

Iam trying to find a good EDM solid .. not much out there IN STOCK so might have to go solid face

I don’t know for sure, but my best guess is they are being made at the C.C.P. plant in Bronson, Michigan.

I have used the EDM comp SFT’s (800-16) and the 2900s. I kind of recall the oil band maybe is a bit low, they work though.

[64-3Deuces]

This question may be a bit off topic but since the discussion is about lifter quality/design and you fellows appear pretty knowledgeable so here goes.

Does anyone know who supplied the HFT lifters to HO Racing Specialties?

HO sold name brand items such as MSD, Power Forge, etc. and their catalog states their cams are made to HO specs by Crane Cams. The lifters don’t list a manufacturer, but I’m guessing the lifters are Crane also??????

I have a set of VL-11 lifters purchased back in the early 80s before the offshore invasion and quality issues.

[PAUL K]

Originally Posted by 64-3Deuces

This question may be a bit off topic but since the discussion is about lifter quality/design and you fellows appear pretty knowledgeable so here goes.

Does anyone know who supplied the HFT lifters to HO Racing Specialties?


HO sold name brand items such as MSD, Power Forge, etc. and their catalog states their cams are made to HO specs by Crane Cams. The lifters don’t list a manufacturer, but I’m guessing the lifters are Crane also??????

I have a set of VL-11 lifters purchased back in the early 80s before the offshore invasion and quality issues.

H-O sold original Johnson lifters before they became Hy-Lift...... Not the same as Crane

[64-3Deuces]

Originally Posted by PAUL K

H-O sold original Johnson lifters before they became Hy-Lift...... Not the same as Crane

Paul K...Thanks for the info. Since I purchased these way "back in the day" as they say I would guess these are good quality lifters compared to some of the lifters available today???? BTW, you're no longer in Sugar Grove????

[4zpeed]

Originally Posted by PAUL K

Bigger the chamfer the better chance you have of destroying a lobe. A lazy lobe with a large chamfer is the worse case scenario. About fifteen years ago I noticed Pontiac had a new part number for RAIV lifters. I ordered a set and they were re-boxed Hy-lift 951R's. Not sure why your lifter has such a large chamfer but I doubt it's within the original GM spec.

Originally Posted by dataway

Don't know what to tell you, I opened the sealed boxes myself. Original 40+ year old GM parts in GM boxes. Both sets the same.
Would be curious to see other examples of original GM lifters in this age range.

The chamfer upgrade may foresee higher lift and RPM's. Seems to me if things start floating around at higher RPM's through effort or even accidentally the big chamfer could be disastrous. If not all at once, over time it would make the valve train unstable, possibly leading to a harmonics issue, premature wear and eventual failure.


Frank

[Formulas]

Originally Posted by dataway

Don't know what to tell you, I opened the sealed boxes myself. Original 40+ year old GM parts in GM boxes. Both sets the same.
Would be curious to see other examples of original GM lifters in this age range.

I have an original 067 cam and lifters from my 1970 400 if your interested i can dig them out for pics

[Jay S]

Originally Posted by Jay S

I don’t know for sure, but my best guess is they are being made at the C.C.P. plant in Bronson, Michigan.

I have used the EDM comp SFT’s (800-16) and the 2900s. I kind of recall the oil band maybe is a bit low, they work though.

I remembered those details wrong on the Michigan plant. It went by C.P.P., and there wasn’t anything done with flat tappet stuff, focus was more on axles for roller assemblies. Compcams owned the company.

[dataway]

Originally Posted by Formulas

I have an original 067 cam and lifters from my 1970 400 if your interested i can dig them out for pics

It would be very interesting to see. I mean the chamfer is pronounced enough that it appears to be a "feature" and I use that word sarcastically

In my head (not the best way to do things) I have a hard time seeing how a chamfer would cause big problems. On most used lifters I've removed the wear pattern often doesn't even intersect with the edge of the lifter. And wouldn't the lobe/lifter contact pressure be very slight at that point in lobe rotation?

Does the sharp edge of a lifter face ever contact the lobe under high pressure?

I can "see in my head" the point at which a lifter face contacts the flat'ish portion on the side of a lobe and then starts to transition to the ramp of the lobe but hard to imagine the edge of the lifter face ever seeing any appreciable force .... now carry it to the extreme, a lifter face the size of a pencil eraser ... yes the edge would see a lot of force, but wouldn't the contact of a lifter face edge on the lobe depend greatly on lifter diameter and lobe profile? IE ... a mushroom lifter the edge would never contact the lobe, a ridiculously small OD lifter the edge would contact the lobe a LOT.

I mean look at heavily worn lifters ... it's the center that dishes from wear ... not the edges.

So perhaps with the OEM lobe profile, and the lifter diameter in use circa 1968 that chamfer is not an issue?

[Shiny]

Can someone help me understand how the size of the chamfer plays into this?

Is it about what happens if the cam lobe starts wearing?

Or does the chamfer somehow affect stability or lubrication?

How far from the center of the lifter (peak of the crown) is the "ideal" or "as-designed" contact point on the lifter? What is the offset from the center of the lifter face if all the parts are new and "in spec"?

I have zero experience looking at the wear patterns and thankfully, even less experience with lifter failure but this is my perception of the contact geometry, which makes me think the chamfer SHOULD BE far away from the contact zone:



Mike

[4zpeed]

Well I thought Paul was talking about the chamfer in the cup not the edge?


Frank

[Shiny]

Wouldn't be the first time I wandered off a trail.... my apologies if I misinterpreted!

Mike

[Formulas]

Originally Posted by dataway

It would be very interesting to see. I mean the chamfer is pronounced enough that it appears to be a "feature" and I use that word sarcastically

In my head (not the best way to do things) I have a hard time seeing how a chamfer would cause big problems. On most used lifters I've removed the wear pattern often doesn't even intersect with the edge of the lifter. And wouldn't the lobe/lifter contact pressure be very slight at that point in lobe rotation?

Does the sharp edge of a lifter face ever contact the lobe under high pressure?

I can "see in my head" the point at which a lifter face contacts the flat'ish portion on the side of a lobe and then starts to transition to the ramp of the lobe but hard to imagine the edge of the lifter face ever seeing any appreciable force .... now carry it to the extreme, a lifter face the size of a pencil eraser ... yes the edge would see a lot of force, but wouldn't the contact of a lifter face edge on the lobe depend greatly on lifter diameter and lobe profile? IE ... a mushroom lifter the edge would never contact the lobe, a ridiculously small OD lifter the edge would contact the lobe a LOT.

I mean look at heavily worn lifters ... it's the center that dishes from wear ... not the edges.

So perhaps with the OEM lobe profile, and the lifter diameter in use circa 1968 that chamfer is not an issue?

pics of 1970 OEM 400 / 067 cam lifter

[dataway]

Thank you.

Hmmm, definitely a chamfer there, not as pronounced as the set I have though.

I can certainly see how as a chamfer gets larger it reduces the diameter of the face, but if the geometry is such that it doesn't contact the lobe anyway, or contacts it with very little pressure ... I don't know, can't see much harm in it. Seems like the sharp corner of a lifter wouldn't last very long against a lobe with any real pressure on it.

However .. I'm by no means an expert on the subject, there may be other forces at work I'm not aware of.

[KEN CROCIE]

I sourced my lifters from Elgin. The lifters were purchased in "tray" lots of 128 lifters. I then modified them with "Tru-Arc" snap rings. Back then there were very few lifter failures, so nobody cared who made them. According to the identification chart from Sealed Power, they were Johnson's

[Pav8427]

Havent recently seen this info and for future reference,
Are there any definative tell tale signs that positively ID a lifter as a specific brand?

[PAUL K]

Not sure how to explain that chamfer is a bad idea. I once waisted time trying to explain millions of vehicles make it to work everyday with pressed in rocker studs and it went over the tops of a lot of folks heads, but I'll give it a try.

Flat tappet camshaft ramps are designed for a
specific diameter lifter. The opening side has to
open as fast as possible but is limited to the
diameter of the lifter. If a lifter has a large chamfer
you no longer have the same diameter lifter at the
liifter face than the cam is designed for. With a
larger chamfer the lifter jumps part (or all) of
opening ramp and wants to dig into to the part of
the ramp that raises the lifter, rather than glide over
it. This starts to chip away at the lobe itself and the
lifter wants to dig into the lobe rather rotate and
follow the lobe. On the closing side of the lobe the
lifter will drop off of the lobe and skip the trailing
end the closing ramp.

[dataway]

Thanks Paul ... that makes sense. I can certainly understand that the smaller diameter the lifter face is, the more side loading it will encounter as it contacts a steeper part of the ramp than it would if it was a larger diameter.

Again to use a ridiculous example ... if the lifter was the diameter of a pencil it would contact the ramp at a very steep location and just break off the lifter. If the lifter was 2" in diameter it would contact the ramp at the earliest point and have a gentle ride up the ramp.

Appreciate the explanation.