4 stroke engine characteristics

[IsleofNinja]

No arguments here..Good to see a refreshing degree of knowledge and experience on the topic..

Most of my posts are 'tongue in cheek' 'gos'.. I figured you obviously know your shit by reading your previous posts, I was just being devil's advocate..

Was never my intention to "fuck up" the thread..Do enjoy a spirited but factual discussion though...It's how we all learn...NOBODY knows EVERYTHING.

No offence intended.

Regards all

[ozten]

(A vivid example of scavenging at work is the flames from the exhausts of V8 supercars on over run)..

.....Over to you 'gos'

Can you elaborate on this more im not quite understanding??

[Gosling1]

.....No offence intended.....

you'll be right mate, none taken ( i didn't see anything offensive - ??)

(A vivid example of scavenging at work is the flames from the exhausts of V8 supercars on over run)..

Can you elaborate on this more im not quite understanding??

I am pretty sure that the flames you see from a V8 s/car on the overrun, are simply unburnt excess fuel that has ignited inside the exhaust due to the high temp inside the 'zorst system ? With so much mixture being pumped into the cylinders under full -throttle, when the throttle is shut off, a major percentage of the mixture for the second or 2 of 'closed-throttle' condition will still be volatile enough to probably self-ignite in a really hot exhaust chamber ?? As soon as the driver is back 'on the gas' these conditions change and the amount of unburnt mixture in the exhaust would be pretty minimal.........not 100% sure about this, but I think this is why you get those whopping flames out the zorst......

[IsleofNinja]

Yep..

Large cam overlap and an 'zorst' designed to help make 620 hp @ 7500rpm .. The flames are as 'gos' said primarily from overfuelling as the loud pedal snaps shut, but also due to the zorst / valve timing actually over scavenging due to the abrupt rpm change and drawing the fuel air mix from the combustion chamber and burning it in the exhaust instead.(If this happens under power you can imagine how much grunt you'd lose until the cam/rpm/zorst are actually synch'd.)

Regards