ano advantage ng more valves in engine?

[buknoy2002]

example a carb engine na 1.3 lliter,
one is 12 valve and the other is 16 valve

whats the advantage?
better mileage? more hp? more torque?

thnx in advance

[yebo]

carb na 1.3? comparing ka ng corolla xl and mazda 323 ano?

well, answer is all of the above. generally speaking less pumping work and better engine breathing mean more power, torque and better mileage.

[hagiber]

Bakit yung ibang highperformance Mercedes SL models ay 3 valves per cylinder lang?

[van_wilder]

depende rin kung anong made... for example benz is 3 valves lang per cylinder pero masmalakas siya... depende... bigay ka ng specific example...

[hagiber]

I think the Merc SL55AMG is a 3valve per cylinder machine... just wondering why Merc doesnt use 4 valves ?

[van_wilder]

i dont know... pagka-alam ko handmade kasi at designed yun makina ng 3valves per cylinder ata...

[ian_rex]

ok. put it this way, less is more. more is less. less valve means more mileage. also, less horsepower since less fuel is contained in the chamber. consequently more is less. more valves means less mileage, but more horsepower. self-explanatory, since more fuel is burned thus more energy is produced.

as in the case of mercedes, 3V / cyl? well, check out its displacement and internal attributes such as supercharger or turbocharger, it is well compensated.

hope my point is taken. :D

[5Speed]

point taken.... I agree w/ you Ian....

[jojo_mouth2]

Originally posted by buknoy2002
example a carb engine na 1.3 lliter,
one is 12 valve and the other is 16 valve

whats the advantage?
better mileage? more hp? more torque?

thnx in advance

3 valves/ cyl engine and 4 vales/ cyl has the same 2 intake valves. therefore same volume of fuel&air mixture that goes to the chamber. advantage lang 4 valves/cyl is it has 2 exhaust valves meaning guaranteed na lalabas almost lahat (if not all) ng burned gases from the combustion chamber after firing, result would be- the volume of air&fuel mixture in the next cycle is close to 100%. then more power is produce...

[hagiber]

Siguro yung single exhaust valve ng 3valve engines is also a little larger in size than the intake valves.. it might improve the reliability of the engine since fewer yung moving parts :-)

[Gen1]

with 4 valves you have an effectively larger inlet and outlet port for the combustion gases. thus a more efficient engine.

the surface area of four circles above the piston is greater than the surface area you can fit on the same diameter circle if you use two or three circles (makes for an interesting calculus test problem if you're the nerdy type).

Down side is a more complicated manufacturing process because of the greater number of moving parts, hence a more expensive engine.

[benchph1]

bottomline is more valves creates more power and better efficiency

[mazdamazda]

IMO, mercedes is sticking with the 3V per cylinder just as a trademark.

but if you compare side by side engines of the same displacement, mercedes' engines have a lower output.

here's a comparison between MB & BMW engines. to note that even though the MB has a higher displacement the BMW still outclasses it. if you noticed, AMG tuned MBs are mostly supercharged to compensate for this.

Mercedes-Benz E240
2.6 SOHC 18V V6
power: 177bhp / 5700
torque: 240Nm / 4500

BMW 525i
2.5 DOHC 24V inline-6
power: 192bhp / 6000
torque: 245Nm / 3500

=======

SLK 350
3.5 SOHC 18V V6
power: 268bhp / 6000
torque: 230Nm / 2500-4800

BMW M3
3.2 DOHC Double VANOS 24V inline-6
power: 343bhp / 7900
torque: 365Nm / 4900