DIYEFI.org Forum

2 * EL34 valves using a custom wound output transistor might be able to (just) do the job of the ignition. (Assumes you don't need more than about 100mJ of spark energy) Hell, since you'd need a custom wound output transformer anyway, you could make it COP! (Or rather, CNP since they'd be rather hea...

I am pretty sure I understand all the basics of the Pattakon valving system... Seriously! And yes, it _IS_ a seriously innovative design. However, it still uses a camshaft (albeit of a seriously radical shape) and, at least in my mind, the inclusion of _ANY_ camshaft must, by necessity, impose certa...

<Snipped somewhat> If this is difficult for normal revs (say 6000 rpm), what about racing revs? Maybe I'm being a little naive here, but it's my 'understanding' that the primary issue at 'race revs' is valve springs (and thus the ensuing valve float). IMNSHO, use of a Hy-Desmo type system (albeit c...

It is not the pressure of the hydraulic circuit that opens and closes the intake valves in the MultiAir of FIAT and in the PatAir and HyDesmo of pattakon. The oil pump supplies oil in a relatively low pressure to just fill the oil chamber during the period the valve remains closed. Then the trapped...

What's stopping them using another such solenoid on a pressurised fluid supply to OPEN the valve too? It is more easy than this. You don't need a second solenoid electromagnetic valve. Take a look at the HyDesm (Hydraulic Desmodromic) at http://www.pattakon.com/pattakonHyDesmo.htm EXTREMELY interes...

YIKES!!! Looks like someone gave the left bank of a V6 a somewhat malignant / cancerous growth!!! <Grins> Nevertheless, it's VERY impressive! So thanks heaps for the pix! It kinda makes me wish I had free access to a decent foundry and a limitless supply of funds. I'd LOVE to be able to 'tinker' wit...

A thought-provoking post indeed! Funny you should mention the two/four stroke switching, I'm in my final few months of my Bachelors at the moment - a couple of the researchers here did that a few years back - http://www.brighton.ac.uk/shrl/projects/2-4sight.php The engine is on show in the main ent...

I hear ya loud and clear... However, I was thinking of the solenoids in question being more similar to a fuel injector rather than acting as the compressor itself. i.e. The solenoid simply acts as a 'switch' to open an orifice to a high pressure supply pump just as any traditional fuel injector does...

For others who, like me, might be somewhat intrigued, here's a semi decent description of MultiAir / Pattakon that has just HELPED my understanding a lot: http://www.pattakon.com/pattakonHydro.htm (And yes, the valves do INDEED seem to 'snap shut' a lot more than with a traditional cam profile.) Edi...

Well... The above post has ruined my preconceived idea of how the Fiat Multiair system actually works... I was under a (perhaps completely incorrect?) assumption that that Multiair system didn't (and I quote) 'SNAP SHUT' the valves at all... I had surmised / assumed that the system simply altered th...