DIYEFI.org Forum

A pressure/volume diagram does not show the amount of power required to move air through a motor. A PV graph shows pressure, not airflow. The intuition is that a PV graph is a graph of 'voltage', and since a PV graph doesn't show the airflow 'current', the 'power' consumed in moving the air cannot ...

Does this mean I'm going to have to concentrate on the 'one-stroke' engine design instead??? (Using a 'double ended' piston). Haha, 'fraid so! Sorry for the delay, I took two quick pictures in the entrance the other day... Looks to have some pretty series valve trickery! http://i1206.photobucket.co...

I'm in my final few months of my Bachelors at the moment Way to lose all respect from MotoFab! You're clearly too young and inexperienced to so much as consider turning the key to start an ICE, let alone explain to him how they work. Haha, I shouldn't worry - I've got used to the "he's too you...

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 entr...

Edit (I hit SUBMIT a little prematurely... LOL): What I don't yet grasp is why they've not been able to completely eliminate the camshaft altogether... The description of the system in the URL above looks to be using a solenoid operated 'relief valve' on a 'hydaulic push rod' between the cam lobe a...

Hi 'TheRevva', the Multiair system is truly brilliant - and in my opinion was completely deserving of the International Engine of the Year Award it received. The system is quite different to what you think - the camshaft does not act directly upon the valves, but rather the camshaft is used to 'driv...

As much as I wish it was, I'm afraid the dyno these tests were performed on does not belong to me, no. Yes, the VAG engines do indeed keep all valves closed on deactivated cylinders, but this is not what decreases pumping losses. Freeing up airflow through the intake system reducing pumping losses, ...

Here we are, test sites 9 through 11. I carried out this tests on an HTP code VAG Group Skoda engine, which is their 1.2L N/A 3 cylinder engine - these tests were performed on an AVL DynoPerform eddy current dyno. All tests were conducted at 2500rpm at 15.3%, 19.4% and 47.7% throttle producing 6.1kW...

Thanks! I read your sign up details, and removed you from n00b group. Go nuts! :-) Ah, I wondered why my other posts didn't need approving - cheers Fred! I'm using the CJ125 IC in the project I mentioned in sign up details, it's absolutely brilliant as one of my biggest specification constraints in...

Ahh, there's nothing better than seeing MotoFab/Jim/Poolside being put in his place. I hope he dares to respond :-) I know I'm new to this forum, a trait which people do not take lightly to I'm sure when challenged - but please be assured my intention is not at all on tread on toes, only to share m...