Hydraulic Followers best?
 

which are the best hyd followers for a bbc gen 6 ? my builder told me Jesel but they dont do hyd once apparently

any one ?

Morels.crane.comp cans.howards and the Johnsons
All good lifters
Just make sure the clearances are in check

If it is under.580 lift, factory GM.....

Doesn't Morel make the GMPP lifters?

Pretty sure Johnson makes GM's.

For what its worth Teague uses Johnson and tells me they are the best. Teague used Johnson short travel, oil hole in my 1250 rebuilds.

I am using the factory GM's at .625 lift with no issues. 170hrs now and still going strong

I have 632 lift

Are these Rollers? Proper spring pressure is a big factor on how long they live. If the roller is allowed to leave the Cam Lobe at any point then the life expectancy is greatly reduced...

yes, and that problem can be exaggerated, when the cam lobe lift is too much for the duration. The fix for that, is adding much higher spring pressures, to keep the lifter on the lobe. But then, too much spring pressure, is also not good for longevity.

Johnson uses a .700 wheel, morels use .750, and some larger diameter body lifters, even bigger. You should talk to your cam company/grinder, and ask what lifter wheel diameter, the camshaft was designed for.

Is this a good time to bring up the subject of oil and oiling too ? Uh, oh.

yes, lol. And probably a good time to discuss the effect of lobe lift vs duration, acceleration of the lifter, .006, .050, .200 duration numbers, and how one lobe can beat the snot out of a valve train and need big spring pressure, vs another lobe, that will be easy on the valvetrain, and not need excessive spring pressure. Like for example, a .410 lobe vs a .370 lobe, on a 240* deg cam lobe, and what the larger lobe does to lifter motion. .

I used to think what made a cam choice the best, was its dyno numbers. I now look for a cam, that won't beat my valvetrain up in a short time, just to make an extra 20hp. .

Hard to determine that way..but we all have our thoughts based off those numbers when given.

Some companies inverse ramps are kept in control...but how ? We can't tell off a sheet of paper right ?

Also, how well lobes are machined can be a big factor.

Valvetrain weight, rocker arm ratio vs lobe design, etc,etc,etc

How would you feel with a .356 lobe with only 218° at .050", 268° at .006" and 143° at .200" ? Yes, it goes 6k or so a good amt.

Good points. I dont think there is much getting around the negative aspect, of increasing lobe lift, without increasing duration. At some point, things become an issue.

There must be a reason, competition cams, crane cams, and many others, do not make short duration, high lift, hydraulic roller, Marine, or endurance profiles. When looking thru any of their catalogs, anything "marine", or "endurance racing", with durations of say, 230-245ish range, .370 is about the max lobe lift they will run, including mercury marine.

I've seen alot of custom cams lately, sporting those kinds of durations, but with .400+ lobes, and .680+lift. Crane, comp, and many guys (including myself), have ran those .370 short duration sticks for years, with 165/450ish spring pressures. But the guys with the big lobes, are running 225/600 spring pressures. I wonder why that is. Probably, because if they tried less pressure, the lifter lofts, valve train fails in short order.

I like new stuff, but sometimes going with whats been proven, works better! I have yet to see a guy running these .400 lobe deals, come back after 300 hours, and say how they've never had a valve cover off of it. It very well could happen, and if so, maybe then I'd try it.

Back in the 90's, lift at/near .600" w 1.7 rockers was extreme for bbc in cars for everything but solid rollers. Even when talking near 250-260 at ,050"

We've come a long way...haven't we ?

We talking flat tappet?

Solid FT and HR

I would say that is towards the aggressive side of things as far as valvetrain/lifter acceleration. Certainly not outlandish, but not exactly a stock 502 mag cam either that might go 1000 hours without taking a valve cover off lol

BBC blocks notoriously have lifter bores not indexed correctly. That poor roller wheel and what that does to stability.

So, .605" , 218 at .050"lobe is milder than say .650" or so 240 at .050" lobe ? How can you tell ?

If you have two cams, both having [email protected]”, one with .370” lobe lift, one with .400” lobe lift, the lobe with the higher lobe lift , will always have a higher .200” duration number. Wouldnt that mean slower opening ramp? Then bring in a 218* @ .050, with the same lobe lift, and you think that wont have a higher acceleration?

I have a question for you mild thunder(or anybody else that wants to chime in),even though I should have checked before I swapped and should really ask the builder I got the lifters from.i went from morel lifters to Johnson lifters and kept everything else the same as my original set up.you mentioned wheel size difference between the johnson and morel lifters.i had some "problems" last fall/winter.redid the motor,same everything just swapped lifters.im going out this weekend to check top end,wot speeds etc.does the difference in wheel size effect performance?i guess the real question is would the engine horsepower output etc. be the same from one lifter to the next?do you know?i know I should have asked the builder but didn't think about it until I started reading about them on oso.

I don't see how it couldn't. The way I see it the larger wheel will follow the lobe profile more smoothly than the smaller wheel.

Curious to see what the experienced hands have to say.

Yes, it will alter valve timing....not much...but it will. It should not move the speedo. I'm sure MK's has a spreadsheet on this.
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On a totally different subject,
A larger wheel will rotate less times for rolling same distance...no ?

the motor has been together for this whole season have had no problems at all.put around 15-20 hours on it.doesnt sound quite the same and it seems to run just fine.could just be in my head.

You may have lost a little acceleration of the valvetrain, by going to the smaller wheel, and a couple degrees of duration in the mid lift area. But, I don't think it would be enough to make a difference. Usually, the area of more concern, is when running a cam designed for a .700 wheel, and sticking an .810 wheel lifter on it, or even a .750. Now, you might see a gain in the acceleration, and could cause valve float earlier, instability, etc. Bottom line, when going with a "custom" camshaft, all these things are , well, things to consider. Otherwise, whats the point of going with a custom camshaft. Theres more to it than a dyno number. In mild setups, this may be an insignificant conversation. On high end builds, guys take this stuff seriously.

Its always a good idea to talk with your builder or cam guy on this stuff. And , nothing wrong with getting a second opinion, from another valvetrain expert. Talk to someone who does this stuff day in and day out, designs lobes, grinds cams in house, has been involved in lots of spintron testing, etc, and understands the importance of a marine endurance setup. Key word, endurance. A half dozen dyno pulls, doesn't equal success. 300 hours in the field, doing poker runs, without taking a valve cover off, is a better testament to the setup.

How many times does a lifter fail, and the lifter gets blamed. How many times does a rocker fail, and the rocker gets blamed. How many times does a valve stick, or come apart, and the valve gets blamed. The ultimate goal, is to not have failure. Period. When engineers at general motors, Ford, chyrsler, toyota, whomever, design a valvetrain, they look at the big picture. It has to do lots of things, make power, be efficient, meet emissions, work with EFI, idle good, and much more, but the most important thing it has to do, is stay together.

I used to think that.........when starting out.

Almost everday I run into a "Why the f*k did they do that." Yeh, it's a tough job being an engineer or what have you for a car company, but there are plenty of things, especially now a days, that will shock you.

Great current example: The Germans make you believe they 'over engineer' their cars.........I never bought into it, and now the world doesn't either.

Yup. Big wheel means lower wheel speed.

The Chrysler buy in changed one company for the worse 10 fold, I worked for a dealer at that time..... What a **** show