adjustable lifters

[quickchange34]

I dont understand why no one talks about lifter wear and how to solve that problem when the engine gets 25000 miles on it or more and the valve lash opens up , then what?. Yes I have a way to grind the stems and have done so and used the nos stock lifters. You will always get wear on the valve stem,lifter,and cam. So how do you set the lash back up if you really drive the car. Using the stock lifters they will not last the total life of the engine without adjustment.

[Brian]

qc34 has identified the same problem I'm referring to; but is more eloquent in how he's stated it; basically, stock lifters tend to 'hollow out' on the top and bottom faces, ultimately incrreasing the valve clearance. Sure, one can reface those faces, but really, how deep is the case hardening? Thing is, they've already worn/deformed, so refacing them decreases any case hardening they had anyway.
The concept of old Henry with the mushroom bottom valves, was to increase the surface area, thereby reducing the wear rate. The original question I posed was about using lash caps on 8BA/shitbox chevie valves, in conjunction with higher lift camshaft, and the early style 'big face' lifters.
Now, as much as I respect Walt's and Ol Rons opinions, if you can't source nos tall stock lifters, but happen to have a stock of nos early lifters, which would otherwise be unuseable, owing to the smaller valve stem dia's of the aforementioned v/v's tending to 'punch holes in 'em', I'm thinking utilising lash caps could serve a two-fold purpose; they would increase the 'footprint' and also take up some of the slack created by the smaller base circle of cam. As well as using good, nos parts, not refaced, thinner old stock lifters.

[flatheadmurre]

If youre engine has 25000 miles the valves and seat can use a resurfacing to...doing so narrows the valve lash.

And and if you surface the lifter down to wear its not worse then what youre running.

Would be interesting to have a spec of material and heat treatening that was done original.

[scooder]

As above, you grind/lap the valve seat/ valve to close the lash.
As for thickness of case hardening, I'm not sure it's a case harden, think there hardness is right through. Ever seen a stock lifter radiused for a 404A or such camshaft? That's a lot more than just a reface cut.
The stock lifters are damn good wether NOS or refaced. And a lot better than most of the aftermarket lifters that appear to be made of cheese.
Martin

[Bluebell]

As I recall, lifters are "Chilled" cast iron.

[flatheadmurre]

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Cast iron is a tricky art...first you have to choose the composition then its heat treatening to get finer or coarser grains.
Amount of carbon.
Adding a bit of magnesium....
Casting it in an metal mold that leads away heat quickly gives you a surface hardening effect.
Yep it would be real interesting to have a firsthand info on how they did it...

[HotRodmicky]

Originally Posted by Ol' Ron

What I don't understand is why are youse guys worried about lifter weight. Back in the day we ran 9N solid lifters and ran 5K with no problem. Unless your planning on running Hi Revs for long perion of time, (track racing) (200MPH Bville runs) why not just use an adj lifter, or just weld up the stems. Fors mad different length lifters and stock chevy valves get them pretty close. I use them with adj lifters and that keeps the thread length of the lifter very short. Street engines very rarely see 4K.
However this has been an exelent educational way of increasing the cost of building a flathead.

Yeah you are right, but would you run a potvin 425 on an adjustable lifter?
Cam lobe is so radical that lifter weight matters .....

[Walt Dupont--Me.]

The early flathead 32 -41 were cast lifters, hollow with slots on the sides like the early Johnsons, they were prone break right in the middle, from 42 on they were some kind of steel. Walt

[Ol' Ron]

Now for some reason we're concerned with lifter weight, To Quote
"Smokey Yunick", lifter weight is a non issue. If it was, nobody would use roller lifters in a race engine.

[HP Hunter]

Lifter weight dont really matter all that much in a street motor.

Just for comparison a Pontiac hydralic and a Flathead solid weigh close to the same.

Harry

[tubman]

Originally Posted by HP Hunter

Lifter weight dont really matter all that much in a street motor.

Just for comparison a Pontiac hydralic and a Flathead solid weigh close to the same.

Harry

Really? I am not questioning what you are saying, just that it surprises me!.

[flatheadmurre]

Originally Posted by Ol' Ron

Now for some reason we're concerned with lifter weight, To Quote
"Smokey Yunick", lifter weight is a non issue. If it was, nobody would use roller lifters in a race engine.

Thats like compairing apples to pears...
With a rollerlifter camwear from a hightension spring aint an issue.
Its an balance as always...and perhaps an non issue that im overcomplicating...
But the law of physics say less weight is good for fast acceleration with less force used.

[quickchange34]

I beg to differ, if you use harden seats and good valves they will be good at 25000 miles. The ware is in the valve stem, lifter and cam. So to get the lash back you need to do a complete valve job? Thats a wast of time and money.If you grind the seats in the block with all that oil in there its really going to be nice on the bearings once the metal gets into the oil. If you pull the valves out and just grind the valves you are removing metal and raising the seat up closer to the tip. Not good !

[Ronnie]

^^^^^
Grinding the valve doesn't change the seat configuration.It will to a small amount close up the valve gap and increase the installed height by the same amount ,not really much of a concern.What is your definition of not good??That is how all valve jobs are done when the valve is ground.The seat configuration is changed when the seat is ground and corrected with a 30 deg and 60 deg stone or cutter to put the seat back to the correct height and width.Cutting the valve accomplishes neither of these.

R

[scooder]

Quick change,
The methods we speak of are how it's done, and how it was always done.
Its the proper way to do it.
Martin.

[quickchange34]

All I am saying here is any time you grind a valve You are removing metal and moving the seat up closer to the tip of the valve. The thinner you get the outer tip of the valve the more prone they are to burning. Why would you want to do a valve job on a engine that only has 25,000 miles on it? Just because it needs to have the valve lash adjusted ? I will stay with the adjustable lifters any time over the nonadjustable ones.If they do go bad I have a way out without grinding the valves and seats in the block to get the lash back.

[flatjack9]

When grinding a valve, you definetly are making it thinner, but you are not moving the contact area on the seat.

[quickchange34]

I know what you are saying and I understand flatjack9. For street engines I use a 45 degree seat face it works better for me on a street engine it gives the valve a wider seat surface. On race motors I do a 30 degree seat.

[Ronnie]

I don't think you could find a measurable increase in hp in a flathead by re machining the seat to 30 degrees and then trying to obtain a valve that will work without taking a stock valve and grinding to 30 degrees. Counter productive,focus on an ignition system and get a bang for your buck. The seat surface width isn't determined by the valve angle,but is controlled by having a multi angle valve seat combination and not valve angle.

R

[flatheadmurre]

Seat width is choosen from the need to get a good seal and not having the valve sink, not much of an issue on a flattie but a high compression diesel needs it done right or it goes bad fast.