Flat tappet lifter failure
 

Curious how many have had this problem regardless of reasoning in last 5 years or so.

Re: Flat tappet lifter failure
 

My boy has had issues that have cost engines while
running the expensive billet stuff.

Re: Flat tappet lifter failure
 

Spring pressure and lifter diameter are factors as well. Stock lifters are good at 380 lb. open and .921" diameter. 500-550 lb. open are another story.

Re: Flat tappet lifter failure
 

I lost one cam lobe, I noticed it after about 100 runs. I’m not sure when it went away. Most likely caused by lack of oiling at low rpm. From what I’ve been told the tool steel lifter, cast cam combination is only good for maybe 200 runs if you’re lucky. Go fast stuff can be a P.I.T.A.

Re: Flat tappet lifter failure
 

Hi George, do you know what your spring pressures were open and closed.

Re: Flat tappet lifter failure
 

Lost a Tool Steel lifter after 6 runs..

Re: Flat tappet lifter failure
 

Hi Paul,
I’m not sure. I didn’t check them.

Re: Flat tappet lifter failure
 

Terry you have a PM

Re: Flat tappet lifter failure
 

Re: Flat tappet lifter failure
 

What's your point. If you want to use a roller cam then either run SS or build a newer Corvette Stocker!

Re: Flat tappet lifter failure
 

The point is many on here have the same canned suggestions , many miss the facts of which there are many, I ,and others have went through all of them many times in the past.

If I just take two rule changes of which were many over the years that have led up to now which are the roller rockers ,and the valve springs ,I am hard pressed to remember nattering nabobs of negativism when those two rule changes were made as to what a few say will eliminate stock as if they even know ,rather that focus on the cost of stock eliminator cars of today' along with the fact of the age of the cars 50 plus years in some cases ,along with the ages of many of the racers that drive them a few on here seem to only be interested in casting there unwanted opinions .

Everyone should have a say as to what they want to run , while we still can if we stay on the course of the way it is in stock very soon there will be no more stock because of the cost, and lack of the parts we need, not the lifters ,here are two strong indicators as to why Electric cars ,but even worse eBay facing fines of $1.9 Billion for allowing the sale of parts that violate the clean air act .
If you think well it won't effect me you're wrong .Already vendors are scared to ship parts , even oil to certain states.

Re: Flat tappet lifter failure
 

As I was in teardown at the Keystones, a D1 racer had Lonnie's ear about a multitude of topics, among them were roller lifters. I am not to tell you what that racers stance was on them, but I will tell you Lonnies take on it. Lonnie said he is not gonna open that door and allow them. He said as soon as he did that, many racers would be buying new roller profile cams, and would open a whole cost to the sport. I think those who are waiting for the rule to change should come up with another plan, whatever that may be.

Re: Flat tappet lifter failure
 

That makes absolutely no sense , if the facts are as you are saying, he is flat wrong about the cost, he should check his facts before making a statement like, it would open up a whole new cost to the sport ,in many cases the older cars are already buying the same billet cam ground for a flat tappet cam ,and having to use tool steel lifters that cost way more than roller lifters in many cases.

Re: Flat tappet lifter failure
 

He had alot more to say about it, but I was too busy while my heads were being poured to hear every word about it. But it sounded like he was very adamant about not allowing this rule to change.
Maybe you and Terry can call him and explain that he's all wrong about his thoughts. I'm guessing he has talked to racers/engine builders about this, because he was pretty quick to talk about it and knows its a topic that is on people's minds. Or maybe he reads classracer

Re: Flat tappet lifter failure
 

Maybe not ,I have no interest in representing the Guy's with the ruined engines, and incurring the cost of bad decisions over the years when it comes to the rules in stock.

If as a group of racers with the non roller cams that feel they want a change they can explain why there is the need to go to roller lifters to NHRA ,
as they have done in the past with the roller rockers ,and many other parts

Re: Flat tappet lifter failure
 

While Reher-Morrison builds some very impressive pieces that I could never afford, I'm not sure they're the place to go looking for advice on your stock eliminator engine. The statement “A low-tension valve spring and a heavy steel valve is the worst possible combination for high-rpm reliability" is very easy to say when you're running "Bracket 2" and can run titanium valves, retainers, and don't care about valve spring pressure. I'm sure David Reher would say running a Qjet and a stock intake manifold is also a terrible combination for high rpm reliability. I think the only logical solution here is for everyone in favor of the rule to just start running roller lifters in their cars, and when (more likely if) a tech inspector sees a car with a roller cam that isn't supposed to, just threaten a lawsuit against the NHRA. At that point it must be their fault that they aren't going to allow you to run parts in your engine that you spent good, hard earned money on, and they will change the rule accordingly. OR, you just fix whatever problem you have with your engine, and run flat tappet lifters like the rest of us.

Re: Flat tappet lifter failure
 

Here we go again

Re: Flat tappet lifter failure
 

If as a group, Racers who are sick and tired of all of the "upgrades and enhancements" that have made it more "convenient" for them to run an Eliminator called STOCK supposedly because the cars that run in it are supposed to be feel they want a change they can explain why there is the need to go back to 1990 rules to NHRA .

Re: Flat tappet lifter failure
 

Bubski is thinking the title of this post should be changed from "flat tappet lifter failure " To " Failure to Communicate " or better yet "Failure to communicate anything other than nonsense " Cheers Chums !!

Re: Flat tappet lifter failure
 

You need to get out of Covina and move into my neighborhood, we can use some one like you. Oak Crest Georgetown Tx, ck it out.........

Re: Flat tappet lifter failure
 

Has anyone done a cost comparison? How about a (god forbid , if ya have a failure) time comparison of available parts?

Re: Flat tappet lifter failure
 

On the six pack car it’s way cheaper to use the DLC lifters than to buy new cam, pistons, machine work on a harder to find block, timing set, bearings, and cleaning everything.

Re: Flat tappet lifter failure
 

Larry,
Not talking about a cleanup in aisle 3 after failure. What I'm asking is it cheaper to run roller lifters/cam vs flat tappet.
Flat tappet coated lifters are $1248 PPPC (quoted 10/5/2023)
Rollers are around $900 Crower
Cam- A Billet is around 8-9 hundred for Big Block and I wouldn't run a cast cam with the weight of valves and spring pressure in a Big Block if they paid me.
Seems on the flat tappets the coating wears off over time (some pretty damn quick lol) and lifters have to be refinished and coated (if ya catch it in time). Cost quoted was $550-$650 (they have to take the old coating off) for coating and around $5 per lifter plus shipping ($35 with insurance) to refinish, etc.
What's the life on a roller lifter running "stocker" springs and RPM?

Re: Flat tappet lifter failure
 

Maybe if you softened your cam lobe up a touch you wouldn’t have to run so much pressure….. I doubt a roller lifter would live with the spring pressure I have. If you think bouncing a flat tappet lifter off a lobe is bad, try it with a roller lifter.

Re: Flat tappet lifter failure
 

Bubski is thinking like OK let's go roller for all !! Since this is "stock" wouldn't it be in the best interest of the rules to stay "stock" ??? So !! Ffford n Chevy "stock" rollers have a .700 lifter wheel diameter !! Every aftermarket roller is .750,.760 not really "stock" where you're supposed to abide by the "stock" rules !! Such as lifter diameter which is enforced but cam bearing diameter is a gray area !! Let's get even more into it !! .250-.280 lobes are not in every cam companies master list !! But Bubski's sure for a few bucks more they'll make a few concessions !! Sooo !! Now you can have a universal roller cam rule and make everyone with a roller go to stock roller diameters and spend some more cash on a set of lifters that are now legal !! However Bubski doesn't know of any race lifters at stock roller wheel dimensions !! However Bubski is sure a few will step up to the "cause" and kindly beat YOU over the head with a "stock" diameter roller lifter and accompanying valve train package !! Maybe it's time to break out the "lifter tru" and reevaluate your camshaft and valve spring choice !! SS has unlimited cam lift and the like !! Show Bubski a 305 with 1.250 lift !! It's not feasible and a BBC with an unrealistic camshaft is also unfeasible !! Sometimes you gotta work within the parameters you're given !! Cheers !!

Re: Flat tappet lifter failure
 

I couldn't have said it any better myself! Thanks Bubski!

Re: Flat tappet lifter failure
 

How come nobody campaigns for a limit on valve spring pressure?

Re: Flat tappet lifter failure
 

I'm good with that!

Re: Flat tappet lifter failure
 

Let's make it fair. If your valve weighs X you get Y amount of pressure. If it weighs Z you get a set amount.

Oh, wait a minute. Didn't they use to do that? Wonder why they changed? Hmmmmm

Re: Flat tappet lifter failure
 

Isn't the class you are running called "Stock". So if manufacture "F" used a better valve spring than manufacture "G". That might have bin a reason to maybe run manufacture "F" engine. At some point it seems people who run manufacture "G" felt entitled to be able to run manufacture "F" type springs. Before you ask, no I don't run a car in stock and have not for over 45 years.



Stan

Re: Flat tappet lifter failure
 

Damn, I thought stock DID have a lift rule. That's why this stocker has .460/.480 lift. Wish I could and (I'm sure others do too) rule more lift. Good point on roller diameter as I'm sure all the later model stockers with rollers (and others) are aware of it.

Re: Flat tappet lifter failure
 

OK the spring pressure needed is a result of lobe profile (yes there are also some other factors). Do all brands have this same problem to the same degree, or is it more a function of lifter diameter? The larger the lifter diameter the greater the max velocity the lobe profile can have. If this is the case then MoPars would have less problems than GM with Ford in the middle.

Stan

Re: Flat tappet lifter failure
 

Yeah, well, there will always be somebody who figures out something to whine about the competitors having an advantage. That's what started this thread.

Doesn't that all get worked out in AHFS and HP factors? That is the assumption with all rules changes that affect engine performance.

The main reason they don't check valve spring any longer is that it takes too long, the expense of the tech staff, the risk of being sued, and the expense of equipment. So the racer is paying for the decision again, and it still is not "fair" for everybody.

Re: Flat tappet lifter failure
 

ASSUME. Dwight, I'm sure you know how to break that down.
AHFS doesn't work.

Re: Flat tappet lifter failure
 

Roller cams will not solve the problem, and will not make it cheaper. It will only make it more expensive, change the failure mode, and cause more problems. It will create another R&D expense. It won't make anyone any faster, except maybe someone who has unlimited funds to invest in camshaft and valvetrain testing.Roller cams will simply cause more problems, and make nothing cheaper.


What will people cry about tearing up next? What rule change will they demand? How much will it cost?


Where will it stop?

Re: Flat tappet lifter failure
 

All this type of unfounded information ,that is just flat wrong again ,and again is not welcome by many ,simply put we are already using billet camshafts ground for solid lifters, that are DLC coated in order to run valve spring pressures well above the limits of a solid lifter at what is already what many say on this site as expensive , so maybe the uninformed may want to go do some of there own research as to the cost before they make false statements , I have said this before many times on this site since 1985 car manufactures have went to roller cams , and before all you opinionated racers express your own views telling others to run a car with roller lifters from the factory ,you may be better served by understanding there is a reason as to why many like running the older cars

Re: Flat tappet lifter failure
 

Now there's some real funny s**t right there!
I'm quite sure that Dwight and Alan are very well aware of the cost of running flat tappets vs. rollers.
YOU may be better served by understanding there IS a reason as to why many like running older cars that came equipped with flat tappet cams in an Eliminator called STOCK!

Re: Flat tappet lifter failure
 

Ya know, you can just never have enough "roller cams for the masses" discussions!
Deja Vu?

https://classracer.com/classforum/sh...ad.php?t=60886

Re: Flat tappet lifter failure
 

Really?


And you have how many class wins with your big block Stock Eliminator engines? Because I have more than 1-2.


Oh, and I have a 9500 RPM+ 396-375 Super Stock engine as well.


Maybe YOU can't make a flat tappet Stock Eliminator engine run. That does not mean the rest of us can't. There are a ton of VERY fast big block Chevy stockers out there running flat tappet cams and having zero problems. Maybe you should ask yourself why YOU can't.

Re: Flat tappet lifter failure
 

Maybe you ,and others would have some creditably if you replied with facts rather to what YOU wrote that is flat wrong , maybe you should check your facts as to if I can make a flat tappet run in stock with zero problems ,I have had not one problem in well over a dozen years running my 396 375 hp in stock @ 8200