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-   -   Lifter Resurfacing (https://forums.maxperformanceinc.com/forums/showthread.php?t=871723)

67Lemons 02-01-2024 08:51 AM

Lifter Resurfacing
 
2 Attachment(s)
With all the concerns about HFT lifter & cam failures I decided to purchase a set of slightly used GM lifters from the 80’s or 90’s for a really good price. The story was that they were used for 5 dyno pulls then swapped out for a roller cam. All the lifters do look like they were only used for a few pulls, two or three have some marks on the face that I can’t feel with my fingernail, pic is below. Regardless my plan was to have them resurfaced so before I pick a place randomly I figured I’d ask the group if there’s a place that you know of that will do the resurfacing?

Jay S 02-01-2024 09:03 AM

Camcraft cams

Egge Machine

https://mizpahprecision.com/pricing.htm

qppcams

I believe Schneider racing cams resurfaces lifter also.

77 TRASHCAN 02-01-2024 09:12 AM

Paul Carter

Jay S 02-01-2024 09:23 AM

Carter could cryo the lifters too.

67Lemons 02-01-2024 09:48 AM

Quote:

Originally Posted by 77 TRASHCAN (Post 6482596)
Paul Carter

Do you have contact information for him?

Pav8427 02-01-2024 02:23 PM

Hopefully not off track.
But with things the way they are today, would this be a 'blueprint' operation to consider?
Most know how this works.
You have pistons in hand before final hone.
You have main bearings in place and measured before grinding crank.
You get the idea.
Disclaimer. I dont have a lot of real world experience, but being a machinist I think about this shtuff.
For sake of discussion lets assume we have good quality parts and machine work is accurate.
Numbers/design are just for theory only.
So picture this. We have a lifter on cam.
Left side of lifter is in line with cam lobe.
Cam lobe tapers .010 down to right.
Lifter has crown of .005
You guys with parts in hand could give an idea on real world numbers.
So now we have cam company A that has these dimensions.
Now some prefer to mix and match companys.
So company B's lifters have .003 crown.
Installed on A's cam you lose .002.
Would this be a case where one would want to have the cam in hand and grind lifters to 'match'?
I know brand and breed of engine design comes into play.
And level of build also. IE. Backyard build vs. Nascar build.
Whats your experience or opinion on the matter?

242177P 02-01-2024 04:33 PM

Quote:

Originally Posted by Pav8427 (Post 6482649)
Installed on A's cam you lose .002.

I've always thought of it like setting up a ring and pinion. The 'pattern' of where the lifter rides on the lobe isn't going change appreciably based on it's crown alone. The taper on the cam would have a more significant role? Dunno.

kyle_blake 02-01-2024 05:12 PM

that is a good question. how about add to the fact a cam can be given to some companies who can build up the specs to what you want by adding material!?

77 TRASHCAN 02-01-2024 08:11 PM

Quote:

Originally Posted by 67Lemons (Post 6482607)
Do you have contact information for him?

520-409-7236

TCSGTO 02-04-2024 08:20 AM

Oregon Cams regrinds lifters also. You have disassemble them and only send the lifter body. They advise to keep the internal parts together and don’t mix and match on reassembly.
Price is pretty reasonable.

Stan Weiss 02-04-2024 01:10 PM

Quote:

Originally Posted by Pav8427 (Post 6482649)
Hopefully not off track.
But with things the way they are today, would this be a 'blueprint' operation to consider?
Most know how this works.
You have pistons in hand before final hone.
You have main bearings in place and measured before grinding crank.
You get the idea.
Disclaimer. I dont have a lot of real world experience, but being a machinist I think about this shtuff.
For sake of discussion lets assume we have good quality parts and machine work is accurate.
Numbers/design are just for theory only.
So picture this. We have a lifter on cam.
Left side of lifter is in line with cam lobe.
Cam lobe tapers .010 down to right.
Lifter has crown of .005
You guys with parts in hand could give an idea on real world numbers.
So now we have cam company A that has these dimensions.
Now some prefer to mix and match companys.
So company B's lifters have .003 crown.
Installed on A's cam you lose .002.
Would this be a case where one would want to have the cam in hand and grind lifters to 'match'?
I know brand and breed of engine design comes into play.
And level of build also. IE. Backyard build vs. Nascar build.
Whats your experience or opinion on the matter?

This might be an interesting read.

Lifter face radius question

https://www.speed-talk.com/forum/viewtopic.php?t=46101

Stan

Schurkey 02-04-2024 04:51 PM

If those lifters were mine, I'd verify that they still have some crown. If they do, I'd pull 'em apart ONE AT A TIME for cleaning and inspection of the guts.

Assuming they look OK inside, I'd put a piece of exceedingly-fine sandpaper (1000 grit?) in the palm of my hand or on some firm closed-cell foam like a better-style water-ski life vest, twist the lifter foot against the sandpaper for about two seconds, wipe 'em off with a soft cloth perhaps with some solvent.

dataway 02-04-2024 05:46 PM

I'd love to see any HFT cam, and any set of lifters sent to "someone" who could positively put proper matching lobe taper and lifter crown on the items, then install in engine and see how it goes.

Don't know of anyone that would do this sort of thing ... but I'd bet if the parts were decent quality to begin with, that it would break-in and run beautifully.

242177P 02-04-2024 06:09 PM

Quote:

Originally Posted by Schurkey (Post 6483277)
... twist the lifter foot against the sandpaper ...

David Vizard recommended figure eights, but his approach was more aggressive

77 TRASHCAN 02-04-2024 06:55 PM

Quote:

Originally Posted by Schurkey (Post 6483277)
If those lifters were mine, I'd verify that they still have some crown. If they do, I'd pull 'em apart ONE AT A TIME for cleaning and inspection of the guts.

Assuming they look OK inside, I'd put a piece of exceedingly-fine sandpaper (1000 grit?) in the palm of my hand or on some firm closed-cell foam like a better-style water-ski life vest, twist the lifter foot against the sandpaper for about two seconds, wipe 'em off with a soft cloth perhaps with some solvent.

A friend of mine chucked some lifters in a drill press and made a jig to swipe the lifter bottoms, restoring the convex deal and improving the surface. David Brown 880 3 cyl diesel tractor lifters were never very common...

1968GTO421 02-04-2024 06:58 PM

My thanks to Stan for posting his link to SpeedTalk. Very interesting and that link had a link within it to EngineBuilder which was quite helpful. Below are links to the two sites mentioned. Thank you Stan.

https://www.speed-talk.com/forum/viewtopic.php?t=46101

https://www.enginebuildermag.com/200...owned-lifters/


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