PSE air cup valve "spring" system?

[wsu0702]

Well now this is interesting I have never heard of this.  Anyone here try this out back in the day?

[Cyclone03]

Oh boy a Pro Stock Paul thread!
I actually think it was Paul’s dad who came up with and built a set up for a race engine ,but getting it all to work in the 70’s ,more than once was a problem.
Think about it , at 7000rpm the valves have to cycle about 66 times per second. I don’t think at the time air bladders small enough to fit could maintain the 400psi needed to control the valves.

Now the real advancement would be replacing the camshaft with a computer that would signal electronic solenoids to open and close the valves. No cam,rockers,pushrods maybe not even a spring.

[frnkeore]

Very interesting!

F1 wasn't using air, valve springs, until '86 and still use them today. The 2006 Cosworth CA, a 2.4 liter V8, was able to attain 20,000 rpm with them. Rules have dropped F1 to 18k now.

NASCAR was able to get to about 9,500 rpm with springs and their large valve heads, much smaller valved, 4 valve engines could go 12,000 with springs but, need air, after that.

I'd really like to know more about the PSE system.

[galaxiex]

I had a PSE catalog "back in the day" around the mid late 70's.

Saw those air cups then and thought it was a neat idea....
Even back then I was unsure how reliable that could be,
and how do the "air bags" stand up to heat and hot oil?


Heck, I might still have that catalog packed away somewhere....


Gonna have to go look for it....

[482supersnake]

https://www.caranddriver.com/news/a15349580/koenigseggs-camshaft-less-engine-explained-watch-it-in-action-video/

This is the new thing.

[cammerfe]

As an alternative, you might google 'desmodromic valve actuation'.

KS

[Cyclone03]

Desmo worked great on my Ducati

[Cyclone03]

“Free valve” is very interesting ,I’m imagining the valves truly following the piston at overlap. Intake full open BTDC then closing slightly when the piston is at the top of its stroke then chasing it down the bore.

The Dyno time playing with that technology ……

[e philpott]

Paul was passionate about the air spring , We were laughing hard at a swamp meet at the air spring and he quickly quit talking to who he was talking to and came over to us to defend the idea , Paul was a character

[WConley]

Today's Formula One engines are the ultimate development of this pneumatic valve spring technology.  They work great, but only for a while.  You have to constantly rebuild them as the sliding seals wear out.  Here's an article if you really want to nerd out on them:

https://www.f1technical.net/forum/viewtopic.php?f=4&t=24821

[TomP]

Interesting reading and pictures on that link!

[machoneman]

Interesting side bar: there is an active and very pricey market for older F-1, LeMans and other long-distance race cars. Vintage iron often goes for 6-7 figure sums. Yet, it appears that air spring engined cars have fallen by the wayside for two reasons.

Collectors and actual racers have shied away due to the necessary and frequent rebuilding of those pesky spring cups. Not cheap to fix and a real pain to maintain, otherwise a catastrophic engine blow up.

The other is that due to their design, there is no way to convert say a 18,000 rpm air engine into a 12,000 rpm conventional wire valve spring engine. Seems the few that are moving are relegated to a museum rather than dusted off and run in non-competitive, show the flag races or the very popular English hill climb series. 

[e philpott]

It would be interesting to try PSE's air system on an old 352 where if they fail you're not out an expensive engine . Solid idea way ahead of its time