Flat Tappet Camshafts & More
 

Interesting Video

https://www.youtube.com/watch?v=NYtMCZYnF7I

Stan

Very interesting. Thanks for posting.

They made the same point I was making in my other post about break in oil for flat tappet cams and how detergents prevent the ZDDP from doing it's job. They also mentioned to get the correct oil formulated for break in and don't use additives because the cam lobe will fail within the first 1 or 2 minutes and the additive is in the bottom of the oil pan and not on the camshaft. Of course everyone was putting down my info.

I run oil that has about 1400 ZDDP oil and have never had an issue with a flat tappet solid camshaft. I always coat the lobes and run them break-in oil.

TV

I run oil that has about 1400 ZDDP oil and have never had an issue with a flat tappet solid camshaft. I always coat the lobes and run the break-in oil first.

TV

Did I mention I love YouTube... thanks Stan!

May want to visit the channel also, Project Pontiac NHRA 2025.

Edit - https://www.youtube.com/watch?v=wZSv7DdnNH4


Frank

Fantastic discussion & as someone on the periphery of the automotive aftermarket it brought to light some things I wasn’t even considering, very candid discussion, thanks for posting.

Some good points made.

Very complex topic. Since I came up thru all of this and had 100 percent success with flat tappet camshafts for nearly half a century now I'm thinking I either dodged a bullet or some of the things I do here with flat tappet engine builds have kept us out of trouble.

For sure at this point in the game I'm glad that I'm out of the engine building business. With all the supply chain issues, rising costs, and poor quality of many of the components that show up these days sitting on the sidelines is certainly a lot more attractive than being right in the middle of the game......

Thanks for posting the video link. Was an interesting discussion among people with respected credentials in the business. Some good and valid points made. One glaring exception though. The group tried their best to imply that throwing a roller cam in your engine makes all the problems go away. That is simply not true. They didn't mention one word about all the roller lifter failures out there. From needle bearings grinding themselves to powder, roller wheels fracturing from improper heat treat, axles galling from improper oiling, noisy hydraulic roller lifters from a host of quality control failures. I agree with them 100%, a roller cam is superior in every way IF and only IF the lifters are high quality as well. Cast iron core availability will continue to be a problem and that is not going away. So it is natural to try and steer customers to roller cams. I get it. But it's still not a guarantee of success. As Cliff said, "it's a complicated situation".

I am nowhere near an expert on this topic but I have always heard that the lifter bore stress is a big problem. Other than talking about blocks being old or out of alignment, they did not really address that problem. Is lifter bore stress only a Pontiac problem?

No, a number of years ago BBC motors where failing cams at a very concerning rate.

It was later found that all of these blocks had been cast in Mexico and the lifter bore machining was so off that many lifter’s in the same block would not allow the lifter to spin.

One good point the group address is that all the ZDDP or whatever miracle oil you choose, won't make up for very bad valve train geometry. Great video. 👍

Mike, When the people in Muskegon, Michigan needed roller camshaft parts, those parts were originally supplied by Harvey Crane and Camshaft Machine Company (the VP of the company was Don Hubbard one of Harvey's people as was Harold Brookshire who later worked for another camshaft company.)

Camshaft Machine Company is still out there designing and machining camshafts for the automotive industry.

Harvey/ Camshaft Machine Company designed the first high volume roller camshafts for the Ford Motor Company for the 5.0L Mustang engines many years ago.
RIP DH and HC).

So a small company (working out of the back room of a shop in the Dearborn Michigan) thought they could design and machine Hydraulic Roller Lifter parts.
Lots of valvetrain failures from this back room shop as related to hydraulic roller lifter parts.

Those are the facts.

So this issue is the people creating the parts (Hydraulic Roller Lifters) not the
basic concept of "can a hydraulic roller lifter camshaft and lifters survive on the street?"

Just saying.

TV

Tid bits from the internet....

Howards Cams lobe list includes the Harold Brookshire designs from when he was at Custom Camshaft Company (Arrington Performance) in the mid/late 2000s.
These would be Harold's last available designs. The Lunati Voodoo's predate his time at CCC.

As of May, 2011 Howards Cams bought cam cores from EPC, Camshaft Machine, Callies, some from Cam Motion and LSM.

Edit: Howards Cams has some Harold's designs that came with the purchase of Custom Camshaft Company.

.

Harold Brookshire was a great camshaft designer and contributed much to the industry. Most people know him from Ultradyne Cams but he was all over the place mostly behind the scenes the brains behind many companies. I never met him but talked to him on the phone a couple times when he had Ultradyne. He told me that he was the first to use a computer to design cam lobes. He said back in the day computers weren't readily available and he would rent time using a computer at a bank to design cam lobe profiles. He told me that he could make an aggressive lobe easier on the valve train better than anyone else, I don't remember everything he told me but one thing I remember he said was he could make the lifter slow down and close the valve gently at just the right point without sacrificing duration and was a pioneer in asymmetrical designs.

And the price difference is seen as well as the quality. Ive pointed this out before. Don't go for the cheapest deal you can find. It's cheaper for a reason.

It’s clear from that video the FT issue isn’t going away and will only become worse, and more expensive. And the push to roller cams while logical is not as inexpensive as mentioned.

"He told me that he could make an aggressive lobe easier on the valve train better than anyone else, I don't remember everything he told me but one thing I remember he said was he could make the lifter slow down and close the valve gently at just the right point without sacrificing duration and was a pioneer in asymmetrical designs."

He designed his camshafts to have no quicker seating velocity that stock cams for a reason. One is that they don't require nearly as much spring pressure to control the valve action at high RPM's. The term often used with this problem is "lifter crash" and it is real and will happen when you use lobe profiles that have super-quick seating velocities and not enough spring to control it, and/or you use heavy components in the valve train. I've witnesses this first hand here, and have had other engine builders observe it when using some of these "modern" fast-ramp cams in their engines.

Also, as it relates to this hobby we NEVER had any issues at all till the early 2000's. Didn't matter if we were swapping out a cam in one of our 4 x 4 trucks in a barn with a dirt floor working off a dirty/dusty work bench, or in a gravel driveway working off a picnic table. ZERO problems. We didn't even know much about "break-in", using "special" oils, lighter "break-in" springs, nothing done at all put put the cams in and go drive the vehicle like you stole it.

Then out of knowhere we started seeing LOTS of lifter/lobe failures followed by just about everyone on the Forums coming in with some theory why it was happening.

I'm in the camp that the demise of Hylift Johnson and the rise of offshore companies filling the gaps started filling the shelves with junk lifters that either didn't spin or so "soft" then ground into dust in about as long as it took me to type this.

By the time Hylift Johnson recovered from their scandal/bankruptsy in 2003 the market was flooded with crappy lifters and those companies that make them are still in the game today supplying sub-par lifters that don't spin like they should and even if they do they aren't made of good materials so the entire deal is doomed anyhow........FWIW.....

I'll have to be the dissenting voice when it comes to Highlift Johnson (sourced from the good source on this forum), at least in my case .. they were the lifters that failed, then replaced with US made Mellings (type with the hard cap on the bottom) that didn't fail. Antidotal I know, perhaps the Melling played better with the Melling Cam.

I wonder ... is the valve train geometry of our "originally HFT" engines the same as the valve train geometry of modern HR engines that last many thousands of miles with no problem? Does the original HFT geometry handicap HR systems? Surely the ideal geometry required for a modern HR is not the same as the geometry used 50 years ago for HFT.

I haven't watched the video but for sure going the roller route isn't cheap if you opt for the better made parts.
My son has sunk about $2500 in his current hydraulic roller setup on his new build, and that's a SBC, supposed to be the cheapest engine to do. LOL