Why The Sudden Interest In Solid Lifters

[toobroketoretire]

Back in the very beginning all engines used solid lifters because they were easy and cheap to manufacture. But in the 1930's hydraulic lifters were invented that made it unnecessary to provide a positive lash to compensate for different temperatures and expansion rates. The check valves used in early hydraulic lifters caused some problems but by the 1970's those problems were solved and today hydraulic lifters are used on virtually every automotive engine.

So my question is why are people going back to the old technology solid lifters when today's hydraulic lifters are so dependable? As a former professional engine builder and mechanical engineer I know solid lifters cause increased valve tip and rocker arm wear along with excessive noise so I can't understand why solid lifter camshafts have suddenly gotten so popular.

Comments?

 

[Hib Halverson]

Back in the very beginning all engines used solid lifters because they were easy and cheap to manufacture.(snip)

In the "very beginning" solid lifters were used because hydraulics had yet to be invented and not because they were "easy and cheap to manufacture".

But in the 1950's hydraulic lifters were invented(snip)

That's wrong, too. The first self-adjusting valve lifter was developed in 1910 by a Frenchman, but they were not used in a high-volume production application until GM developed a hydraulic tapped first used in the "452" OHV V16 engine Cadillac offered starting in the 1930 model year.

(snip)I know solid lifters cause increased valve tip and rocker arm wear along with excessive noise so I can't understand why solid lifter camshafts have suddenly gotten so popular.(snip)

You KNOW that?!ad
How so?
WHAT FREAKIN' EVIDENCE can you post here that proves mechanical lifters cause increased valve tip and rocker arm wear?!

As a former professional engine builder and mechanical engineer

You know, "toobroketoretire", you've been saying that since you first joined the CAC, however, based on the substantial amount of inaccurate information you've posted in a number of different places on this site, how about posting a little resume information which might patch up your credibility which, I hate to say is...well, to be honest...it's in tatters.

For what engine builder did you work and how long did you work there?
Where did you go to school to get your ME?
Virtually all MEs working in the automotive field are members of SAE. What's your membership number?
For what firm(s) did you work as a "mechanical engineer"?
What types of systems or devices did you engineer?

 

[Vettehead Mikey]

I'm not aware of any 'sudden interest' in solid lifters. Are you confusing them with roller lifters?

 

[kpic]

Hib
Toobroke... is a mechanical engineer or so he says..

As a former design engineering professional of 45 years; I highly doubt his engineering credentials.

 

[toobroketoretire]

When the lash is taken up in Chevrolet engines the ball-pivoted rocker arm "taps" on the corners of the valve tip which eventually rounds them off. But with hydraulic lifters the rocker arm stays in constant contact with the valve tip which greatly reduces wear. Hydraulic lifters may have been used on the first Cadillac engines but they weren't successful until the mid 1960's when the ball bearing check valve design came along. Prior to the ball bearing check valve they used a "piddle valve" which was a little hardened steel disc about 3/8" diameter and real prone to leaking when carbon deposits got stuck to it. Back before the 1960's it was very common to take lifters apart and clean them in carburetor cleaner to remove the deposits that caused them to leak down so easily.

But my question was why are solid lifter camshafts getting so popular when they offer no gain whatsoever in a street engine? People just enjoy fussing with their engines?

 

[Tom Bryant]

I have to ask. I am not aware of a resurgence in the use of mechanical lifters. The auto manufacturers aren't using them and it's rare to read any engine build article that uses one these days. Occasionally for an comparison test or in all out racing engines, but not often. Even flat tappet hydraulics are becoming rarer with the wide use of hydraulic rollers. Solid lifter street cams are few and far between in the cam grinders catalogs these days. I read a lot of stuff every month on both the various forums and in print and just about any reference to a solid lifter cam is in relation to a vintage engine build where that is what was used originally or in certain classes at the drag strip.

Just where is this resurgence happening?

Tom

 

[LLC5]

I'm not aware of any 'sudden interest' in solid lifters. Are you confusing them with roller lifters?

Probably.

But, as a self proclaimed " former professional engine builder and mechanical engineer" I can see how he could easily get them confused, if indeed he even knows what they are.

 

[kpic]

There isn't a resurgence.

Back in the day, the "simplistic" solid lifter was needed. Over the years, the design and capabilities, the hydraulic lifter came a long way. Design came a long way when TI and HP came out with a calculator.

I dislike dating myself....

 

[Hib Halverson]

Hib
Toobroke... is a mechanical engineer or so he says..

As a former design engineering professional of 45 years; I highly doubt his engineering credentials.

Well....I'm keeping an open mind. I'd like to let him establish credibility

 

[Hib Halverson]

When the lash is taken up in Chevrolet engines the ball-pivoted rocker arm "taps" on the corners of the valve tip which eventually rounds them off.

Provide some evidence of this problem. I've never observed that happen unless the engine has rocker arm geometry which is FUBAR or uses valves made of substandard material. I've worked on GM V8s with mechanical lifters since the late-60s and have never seen the problem you cite in a properly configured engine.

Hydraulic lifters may have been used on the first Cadillac engines but they weren't successful until the mid 1960's

Again, how about some evidence that early-style GM hydraulic lifters (Cad. starting in '30, Olds in '49, Chevy in some engines starting in '50, Buick starting in '50 and Pontiac starting in '54) "...weren't successful."

until the mid 1960's when the ball bearing check valve design came along. Prior to the ball bearing check valve they used a "piddle valve" which was a little hardened steel disc about 3/8" diameter and real prone to leaking when carbon deposits got stuck to it.

You have no idea what you're talking about.:nono Early GM hyd. lifters were all the ball-check type. The Chevrolet "piddle valve" lifter was not introduced until 1965, but it wasn't until '68 that Chevy V8s used them across-the-board.

prone to leaking when carbon deposits got stuck to it. Back before the 1960's it was very common to take lifters apart and clean them in carburetor cleaner to remove the deposits that caused them to leak down so easily.

"Carbon deposts"? What the heck are you talking about? There is no combustion inside a lifter nor are the lifters exposed to combustion, thus there will be no "carbon deposits". They only appear on piston tops, valve faces, chamber walls or plug tips. That said, you could have oil "sludge" deposits or dirt in a lifter if the engine oil was poor quality, had not been changed or the engine was subjected to frequent starts without-warm-ups.