BILL WZOREK
Well-known member
When you resurface lifter's are they flat across or is there a small recess arch to them.( I think I know the answer but would like to know for sure)
THANKS
THANKS
Resurfaceing Lifters ???
- Thread starter BILL WZOREK
- Start date
Lifters have a slightly convex surface. The Ford drawings show them at a radius of 96 inches. Orbital grinding machines were used by companies like TRW to produce the proper surface. I am not aware of anyone who resurfaces lifters to the Ford specified sphere. Instead I get as close as possible with a straight grind to the same convex segment height. In some ways the "substitute" method is slightly better than the Ford specified method.
chuck stevens
Well-known member
Bill, I had a set done flat, I knew they should be convex, but none of the local machine shops could do it. They are in my 40 it has no miles yet. I hope the cam lobes are at a angle enough to make the lifters rotate. Will- we have no zinc in the oil anyway so I guess flat tappet cams are doomed.
Hey are you guy going to make the NE Pennsy tour next month, I hope to see ya, Chuck
Hey are you guy going to make the NE Pennsy tour next month, I hope to see ya, Chuck
cbillelder
Well-known member
I had a set reground for my engine at Delta Camshafts in Tacoma, Washington. My local engine rebuilder sends all his lifters that need regrinding to them.
BILL WZOREK
Well-known member
Ol'Ron
So I think what you said is that with our street engines it " WOULD " be Ok to resurface them Flat.
If that is correct, WHEN or WHAT size ( I may be using the wrong words here) How BIG / STRONG / C.U.Inch / or # of spring pressure would you think that one should start thinking about Resurfaceing them with the Convex in them?
THANKS every one for the replies
So I think what you said is that with our street engines it " WOULD " be Ok to resurface them Flat.
If that is correct, WHEN or WHAT size ( I may be using the wrong words here) How BIG / STRONG / C.U.Inch / or # of spring pressure would you think that one should start thinking about Resurfaceing them with the Convex in them?
THANKS every one for the replies
Pete
BANNED
Roger on all that.
As far as we have been able to determine, Ford never had any equipment to grind a true radius on the lifters. At a 96 inch radius, it is extremely difficult to measure a .0002 rise in 1/2 inch. It appears as a straight taper.
In any case, if it were a true radius, there would be POINT contact between the cam and lifter which would result in a much higher wear factor.
Modern practice is to grind the lifter face with a straight taper to match the taper on the cam lobe. We have also found that the finish on the lifter face and the cam have a lot to do with how long the combination will last. Some of the modern grinders made specifically to do lifters do not qualify.
"Been in the cam business 60 years"
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Ol' Ron
Well-known member
On a street engine, liminiting the RPM to 4500 or less I see no reason th run more than 50lbs with the more aresive cams like the L-100 or the 1007. The 400jr requires alittle more. Stock cams seem to work wekk with the original 40 lbs. Running a 404 radius lifter cam we started wit 85 dual spring setup and the cam and lifters were tost after one season. We ran 65 on the 400 jr for 3 years untill we switched to the Erson D410. a number of lifters on the 400jr were bad and a gew lobes didn't look so hot.
THen they went to SBC
THen they went to SBC
Pete
BANNED
I have never known anyone that put a hot cam in a flathead that limited their rpm's to 4500. That's like buying a Corvette to drive one block to church.
A 1007B has a lift rate of .008 per degree squared.
50 lb on the seat will get you about 3500 rpm safely.
I have never seen an L100 in the flesh so I can't say about that.
A 1007B requires 70lb minimum for 5500 rpm. Add 300 rpm for stock lifters.
A 404A with modern oil will run a whole racing season with minimal wear. We run 110 lb on the seat with those. Single damped Chevrolet springs with titanium retainers.
Modern racing oils really make a difference from the old days.
Ol' Ron
Well-known member
I find that my mind might play games with me or the air on the east coast is different than yours. One of the reasons I limit the RPM to 4500 is because of the weight of the ols lead pistons we used. At hight RPM theu would hit the head. The 284 Hydro engine had an L-100 with 60 Lbs on the seat and turned 5500 max HP was 175 ! 4800 Richards 276 has 50 on the seat a will turn 5K with no trouble. Excessive spring pressure in a street engine that spents 90% of it's life under 3K is only asking for trouble. Now, I also Have several engines out there with the 1007B in them, They also have 50lbs on the seat and they also will run to 5K, But these are in street engines. I run my pistond to .050" or less head clearance. "Back in the day" with those old Jans pistons you needed .100 piston to head clearance to keep them from hitting the heads. The man I learned from was Bill Barth of Bridgeport Ct. He build some of the strongest engines in the area, mostly SBC . He was a great teacher. He said you have to try everything to learn what works and what doesn't.
Robert Dip
Senior Member
Ol' Ron.....interesting about your comment on the Jahns cast pistons and needing the .100 clearance. My '39 Coupe is an old build from the 50's, and the engine is still in new & unworn shape. Since I did not want to remove the old Navarro heads for fear of damaging them...being on there for 50+ years, and the engine burns no oil, runs great, I simply removed the oil pan to looksee what was in there....surprise....1CM Merc crank, 29A rods with floating bearings, Jahns 'racing pistons', Johnson adg. lifters, Isky 77B cam ( the one that you don't like ), bored.125 over, twin 97's on the Navarro intake, etc....engine pulls like the stinks in high gear. Question ( not to take over this forum lifter question ) when doing a compression test, it came in at 200 for each cylinder ...one read 190.....does 200 seem correct....?? The valve springs are unknown to me, nor does the pressure after 50 years of sitting around....what do you believe that the max rev. I can pull safely with this combo?....Robert
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Ol' Ron
Well-known member
WOW!! that does sound like a stump puller. Great bottom end, cam is a good bottom end and should rev over 4K with no problem. But you just don't know until you try it. Never saw a flathead with that much compression. I just finished my 280, which has a stock EAB cam in it and .045" piston clearance. I expect that to have a high static CR.
Let us know how it runs.
Let us know how it runs.
Robert Dip
Senior Member
Thanks Ron…..engine runs great, and at 276 cu. In. with a 4” stroke, it really pulls nice in all gears. I installed 25T L-Z gears, as the original ’39 gears were not in sink with the torque. With a 3.78 rear and 820 x 15 tires, it needs a little care taking off from a dead start, but within seconds, it picks up to 35 mph in first gear without a problem. Second is nice now since I do not have to go into 3rd between short blocks in my neighbourhood. I install a tach to keep an eye on the revs…..by the way, welded weights on the crank indicate a proper balance job was also done. Someone seems to have done a proper build back then….using what was available at the time…cast Jahns pistons. This car is now fun to drive. Robert
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BUBBAS IGNITION
Well-known member
Many of the black and decker valve grinder machine had the convex lifter grinder built in. In the day we used it a ton with reground camshafts etc.......
Robert Dip
Senior Member
OK....now a lifter question....I have an old rebuilt engine.....the good cylinders are like new, no ridge....water got in on some....bad...but, it has hollow adjustable lifters. The lifter galley is clean and without rust. Question...I plan to use these low mileage lifters with possibly an L100 reground cam....no racing in question, just street use...can I use these lifter as is without the resurfacing. Robert
Pete
BANNED
It is NOT recommended.
oldford2
Well-known member
Re: Resurfaceing Lifters ??? Bubba
Hey Bubba,
I have a Black and Decker valve grinder. How can I tell if the convex grind is built in?? I will put an old lifter in and regrind the face and then see if a straight edge shows a convex grind. If it does, that means a valve stem would also have that grind. Last resort, did out the manual and see if it is mentioned.
John
Hey Bubba,
I have a Black and Decker valve grinder. How can I tell if the convex grind is built in?? I will put an old lifter in and regrind the face and then see if a straight edge shows a convex grind. If it does, that means a valve stem would also have that grind. Last resort, did out the manual and see if it is mentioned.
John