Maybe because they were never offered on a American made car. (my opinion).
There are no "pneumatic lifters"... only springs. Think of this system as exactly like the ones currently running today in PS, with ONE CHANGE: The metal valve springs are replaced by a cylindrical "spring" that is full of compressed air... and that's the whole change. Same cam, same lifters, same pushrods, same valves... just different springs to close the valves.
The "worth" of this change, irrespective of any operational improvements (due to better control of the valve due to less of a problem with harmonic-induced misbehavior) would be simply all the dollars that would NOT have to be spent on mega-buck valve springs that destroy themselves, just doing their job. I don't know if such a system (pneumatic spring setup for big, heavy valves like the ones in these 500 cubic-inch engines) even exists, but if it does, it might be a large one-time cost, but those air springs probably don't wear out like a metal spring does.
However, it likely will never happen because, although NHRA steadfastly contends that it is making every effort to keep the cost of racing down, it sure doesn't seem that way, when they ban these springs that use cheap gas and don't break, instead of short-lived, expensive conventional springs.
Bill - if someone makes a reasonably priced pneumatic valve spring for this application, I can't find them. I did find Del West Engineering, which claims to offer "The only commercially available design and manufacturing team for pneumatic spring systems.". The web site warns that there are "significant" costs to apply such a system. If we are talking Formula 1 level significant costs, you could probably could fund every NHRA P/S team for a year for less money than developing systems for three different motors.
Here is a question: Does the pnumatic spring just replace the coil spring --or is it an accuator? (meaning in actually opens + closes the valve eliminating the need for a camshaft ,lifters,rockers,timing belt etc.?)
I wonder how many of you know that a PS cam rides on nine cam bearings?
Who says racing is about inovation?
How do you think we got from 140 MPH in the quarter-mile to 335?
For a long, long, time, NHRA's motto was 'INGENUITY IN ACTION." Innovation was the whole rationale for that motto.[/
Why would a class with STOCK in its name come out + develop something that the auto makers don't even utilize?
Oh really? When did automakers utilize Holley Dominator carburetors and the "HEMI" engine that currently lives in MoPar Pro Stockers?
Hell-NHRA won't even allow fuel injection.
That's right, and that flies in the face of your argument that "automakers don't even utilize." They haven't "utilized" carburetors for over twenty years...
What if they did allow it? Is it allowed-or mandated? car company A is all for it while company B wants nothing to do with it. A starts run 6.30's right off the bat-company B cries foul. Add weight to A? Look how good that works for PS/B.If I were NHRA, I wouldn't change P/S-full fields covered by the blink of an eye works just fine.
It would just be allowed; anyone who wanted to use it, could. A simple change of how the pressure is applied to close the valve isn't going to make any earth-shaking performance changes in the way these cars perform. That's not the reason for doing it. It's just a way to get around the monstrous bills for valve spring replacement. Metal springs wear out incredibly quickly, and they're not cheap! Air never wears out... the egregious and ongoing valve spring expenses that P/S teams are enduring with the current setup would diasappear, along with the maintenance nightmare that metal springs create.
Here is a question: Does the pnumatic spring just replace the coil spring --or is it an accuator? (meaning in actually opens + closes the valve eliminating the need for a camshaft ,lifters,rockers,timing belt etc.?)
Have you seen the crowds at an IHRA race? Muchless how many watch an IHRA PS session versus NHRA?
Adding available parts to increase performance to PS isn't going to increase many things other than teams choosing to race elsewhere. Hell whats the point?
Pro Stock fans watch because the racing is decided by thousandths of a second.
It would just be allowed; anyone who wanted to use it, could. A simple change of how the pressure is applied to close the valve isn't going to make any earth-shaking performance changes in the way these cars perform. That's not the reason for doing it. It's just a way to get around the monstrous bills for valve spring replacement. Metal springs wear out incredibly quickly, and they're not cheap! Air never wears out... the egregious and ongoing valve spring expenses that P/S teams are enduring with the current setup would diasappear, along with the maintenance nightmare that metal springs create.
It is simply a spring made of a cylinder that is approximately the size of current metal springs, and contains pressurized air, that's there to close the valve; nothing more.
This isn't about performance increases; it's about money.
what kind of ridiculous baseless questions are these?
surely you are not seriously putting the blame of the IHRA woe's on their Pro Stock division are you?
Why don't you bring up ADRL's extreme pro stock?!?
Why didn't you bring up a relevant comparison like "Which series has a larger percentage of the people attending a race watch Pro Stock?"
I bet hands down its ADRL.
You simply cannot make a decent comparison of IHRA vs NHRA because no one goes to those races period, not just because of Pro Stock.
I thought the point of Pro Stock was the performance ie. extreme attention to detail in maximizing the motor and minimizing the parasitic losses.
Well heck I believe you just saved the NHRA and Pro Stock teams thousands of dollars.
Give em some briggs and stratton flatheads with a big shell and they'll be side by side the whole way down the track for even a LONGER amount of time.
Shoot, if thousandths of second is the standard then how about thousandths of a second over 25 seconds?!?
Just changing the class rules to decrease ET's isn't innovation. Innovation is found when ET's decrease while within the same rules.
As far as the ADRL, I have only been to three races last year and two this year. The place was packed before and after the Pro Stock class was brought in. BTW, did you know ADRL PS rules mirror IHRA rules? Why is that? Because in order to get a bunch of PS teams to race at the ADRL, the PS teams wanted to race at a new venue yet not have to develop a new combo.
Toby,
If the increases in spending that you mention, to take advantage of pneumatic valve springs' ability to make possible higher rpm's, are going to be such a negative factor in the switch to "air" springs, then maybe they could scotch it at the outset by requiring rev limiters on the engines using "air springs."
It's not like this NHRA-mandated, "rev limiter" capability doesn't exist; they use them on T/F and F/C motors currently, don't they?
Seems to me that such a rule would nullify all the reasons you mentioned that these new "air" springs would add to the cost of racing in Pro Stock. They were all rpm-related, were they not?
And, they could dodge the current high tab for metal springs without suffereing the R & D expenses that were going to be related to increased RPM levels with the "air" springs.
Could that work?
Pro Stock isn't the only place these springs could be used to advantage. I don't know what the cost is for a season to supply valve springs on an Alcohol Funny Car like Ace Manzo's, (or, a TAD) but I'll bet it's astronomical.
A lot of Comp Eliminator cars also run stratospheric RPM's, but I don't know how viable these "air" springs might be on those engines.
Lots of questions; not many answers...
Sorry...
Bill
Bill;
With the current state of the economy it does not make any sense to make a rule change that would increase the cost of racing.
In fact it is true that there are lots of ways to increase the performance of the current PS car without making new exotic expensive parts legal. And all it takes is MONEY!!!!!The teams that have the money to do R&D can find plenty of areas in the vehicle to spend their money,even with the existing rules.
If you have been following the class recently it is obvious that there is a big gap between the teams at the top of the class and the teams at the bottom.
At Sonoma this weekend there was a tenth of a second spread from top to bottom. This situation is only going to get worse if rules are made that continue to increase the areas where the teams with money can spend that money.
Two years ago ,at a Pro Stock Owners meeting I suggested that we put a 10,000 RPM limit on engine speed. I guess you know that the high profile teams did not support my idea. I can assure you that if NHRA would have passed such a rule the cost to race PS today would be much less, and there would be a couple of more teams on the circuit.
Don't get me wrong I am not blaming NHRA for this. I am sure that if the PS owners had gone to NHRA and asked for a rule change it would happen. After all NHRA did put an RPM limit on the fuel cars.
It all comes down to the "Golden Rule".....those with the Gold ----Rule....and the teams that have the money to invest in the new technology will continue to resist any restrictions on exploring that new technology.