Ever wondered what is going on under your bonnet.
Then this should interest you.
Sadly, us poorer cousins on 8 pluggers can only wonder what we are missing...
The 8 valve twin spark engine is much underrated and IMHO much more suited to Jazz than the i-vtec (have driven both). The 1.8 vtec in the Civic is great because of extra 500cc.
http://asia.vtec.net/Engines/lseries/index.html (go back to home page and 'technical articles' for some really good write-ups on Honda engines).
Everyone knows that power is 'the size of the bang x the number of bangs per minute' - petrol engines have a greater rev range than diesels but people still think diesels are somehow 'more powerful' (mainly because of the low down torque) which is IMHO where the 8 valve i-dsi scores over the i-vtec in Jazz because the i-vtec is pants below 3K.
The fact is that diesels have long stroke engines (to get the very high compression ratios) which means larger crank diameter (and larger heavier engines) and more torque, but less revs (piston speed and flame propagation limits). So as I have said before petrol engines are capable of producing much more 'power' than diesel engines, (look what happens when you put a turbo on a 1 litre petrol engine) but diesels without a turbo are just a slow revving low powered lump. The gearbox sorts out the torque that you get at the driving wheels. I have attached PDF of a great article that someone did on Civinfo forum explaining torque and power.
I read somewhere that the 'ideal' capacity per cylinder is about 300cc to 350cc - above that size efficient filling and flame propagation suffer.
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