Technical Reusing old cam & lifters

They took the material off the heel ONLY. Fairly common practice in the "olden dayz".
They usually made a metal 2 piece template from an existing performance cam lobe and hand ground the lobes to fit the template.

 

This is another of those things that can't be done, but we did it in the old days.

 

You can only do that stuff and get away with it when you dont know any better.
"Poor folks got poor ways" was something I used to hear a lot.

 

if you remove metal from the base (back) of the cam the lifter now sets farther down in the bore and must travel farther to get to the top of the lobe.

 

You have to adjust the clearance out by adjustable lifters on a flathead or adjustable rocker or pushrod on an overhead.

 

Doing it right is the best insurance you are going get. My peace of mind is worth it.

 

or longer pushrods or grinding the rocker stand so its shorter. More than one way to skin a cat.

 

If someone ground metal off the base circle of the cam.....the part where your lifter is touching when the valve is closed.....then when the unground lobe rotates to push the lifter upwards, it will push it farther upward because you changed it's mechanical advantage. Once you do something as stupid as that, expect your engine to grind it's ownself into submission shortly thereafter.
Camshafts and lifters are precision parts, you do not change them with the tools you have in your home garage. Besides having no way to keep the surface even remotely parallel to the rotational axis, you would have inconsistent distances from the centerline of the rotating cam and the finish on the surface would be too rough. Couple that with the fact that you would also change the critical interface between the rocker arm and the valve. It's a totally moronic idea to ever do something like that. They might do it in a country like Cuba because they have no choice, but it's definitely not something anyone should try.

 

Correct on all counts except the lifter touching the cam when valve closed and finish.

HOWEVER, it was done successfully many times.
One in particular I remember in the Pacific NW. It was a fuel roadster with a 296 flathead on 100% nitro.
I made the templates for them to do the grinding.
The timing on the cam turned out to be 40/80......80/40. with .450 lift.
They set trap time record for the strip that day and got top eliminator.
How many flat lifter flathead Ford cams have you ever heard of with that timing????

 

I'm not sure if you could even buy new racing cams in the early days of hot rodding ('30's - '40's) which is why guys bought "reground" cams. Probably how the big name cam guys got started in the business.

 

At one time almost all the assembly line rebuilt engines has reground cams and resurfaced lifters. I used to buy just the lifters from a local rebuilder to use with good looking cams

 

Yes, rough cast billets were available but only in large quantities.
Steel billets were readily available but costly as same today.

 

SO.... is Racingroger going to come back and upset half of you here by going one of two ways or leave you all arguing of the pros n cons, or give up and move on?? JW

 

To the flathead guys.
The man that assembled my 8RT(8ba guts into a fresh 8rt block) told me that flatheads are not as sensitive to cam and lifter changes like an overhead valve. I was concerned about reusing components from one engine to another. He said they swapped that stuff around all the time. He was an old racer.
The engine did fine. He said the only real tension or load on a flathead is from the valve springs. It's not having to push a push rod and does not have near the same stress as an OHV.
Like everything else take that info with a grain of salt.

New cam vs old cam? Both are gambles. A new can wipe out just like an old one and vise versa. If I had a vintage cam on the shelf I would not hesitate to use it if it fit my needs. Best practice with a used cam....old cam with new lifters. Worst practice with a old cam...Old cam with mismatched old lifters. That's asking for it.

 

I'm back! Dang, I get busy for a day or two, and when I come back, holy crap! 8 pages of fantastic information and great comments. So let me get on with my next post with my decision...

 

When I first asked my question, I was trying to figure out a way to get this engine running again on a very limited budget, and quickly (this is June already for crying out loud). I was trying to decide where to cut corners and what to buy new. After reading through all the responses and having all my questions more than adequately answered, I decided I need to take a step back, take a breath, suck it up, WAIT, and do it right the first time. Yeah, it doesn't make much sense to ultimately put double the effort and money just to get something NOW NOW NOW. When I first disassembled the motor, I just figured on using new parts pretty much all the way around, when I got around to the rebuild. That was over 20 years ago, and things change like they always do. I'm now retired and have the TIME, but being older, I'm now feeling that pinch of time slipping away. Oh, and having the time *does not* mean you now have the money.....so I will wait, save money up, and figure out how to choose a new cam and lifters.

Thanks to everyone who participated in the thread -- it's been very valuable to me!!!!

 

Good decision. JW

 

Sad to say, but I know how you feel, and I am only 45. Had I gotten my head out of my azz 25 years ago, I could be 25 years further down the road than I am now. Live and learn I suppose. Also, the price of living a life of caution and trying to prepare for what if....

 

I just read this whole post and sort of chuckled about some of the stuff I have been forced to do because of lack of funds or trying to get the edge on my competitors.
I street raced a 64 impala 327 4 speed . I put a set of used solid lifters on a used hydraulic cam. Out ran a lot of brand new road runners and GM muscle cars with that old beater.
I ran a cheater hydraulic cam in my dirt track car with solids.Just set the valves like a solid cam and turned it 7 grand every lap. Won the track championship that year.
Pulled a used cam out of a blown up big block . Took the lifters out another engine because the first had been turned upside down and the lifters fell out. It ran 2 years in my race car hauler.
On your Ford I would at least buy a set of new lifters for your used cam. Use some good oil that has the additives for flat tappet cams. Should be fine. Good luck.

 

and The fact is many cams where "Belly Ground" and it worked? I had told my children about belly ground cams. and My son Chris took the cam out of his Go Kart and filed on it. He got it running and it ran like crap. popped and backfired. He was about 9 and was always messing with 1 cyl engines. He had six of them running at the same time. and would adjust the carbs and tune to see how slow he could make them idle. The one he ground the cam on he installed a long section of pump pipe on it. the noise it make sounded like some kind of firearm. Theres a kid on U tube (Cruddy Corn Stalks) that does the same kind of Stuff. I get a kick out of watching him.

 

May take a little longer but you won't regret doing the job right. HRP

 

Yeah, and I knew that -- just panicked over it being June already (almost July) and I'm still nowhere with this. After taking a breath, I'm going to take the advice to do the job right -- when I'm properly prepared (and saved up the money).

 

If the rod and and main bearings are ok u can reuse them.


Sent from my iPhone using H.A.M.B.

 

This is a great thread !

 

Regarding reusing rod and main bearings, if you are tempted to reuse them you should check the clearances with plastigauge.

A few years ago I checked the rod bearings on an off topic Ford four cylinder and found they were at the top of, but within tolerance. I flipped them top to bottom since pretty much all the wear is on the top shell and reinstalled them.

I've since flogged this little beast for a lot of miles and it still sounds good and runs very well, but does clatter a smidge for a second or two on startup.

 

What has changed or were Y blocks different Back in the day I changed a lot of cams in Y blocks and never changed lifters because it is a pain and no flat cams. I did run the stock springs for the 1st 1000 miles and then change. I am a firm believer in light springs for breakin on a flat tappit cam. It's not that hard to change springs.

 

Or you could just get this and a Comp Cam decal Budget friendly and peace of mind by not using old parts. https://www.summitracing.com/parts/sum-k3600/overview/make/ford

 

Yes we all have different ways of tackling a repair. Personally, if I am in it that far I am going to go all the way and put quality new parts in it. If you have everything taken apart to replace the cam and lifters I figure I might as well do it once. He can check if he nicked the bearings when he pulled the old cam, but if he has the mindset to reuse the old cam and lifters he probably doesn't care either way.

 

And just for arguments sake , if someone has the mindset and is going to reuse bearings , lifters and the old cam then they wouldn't ever touch my engine. Do it all in or don't. I can sleep great at night. Hey it's just me.

 

Scotchbrite the stain off the cam and lifter face..any ridges you can catch a nail on? don't use it.