SOHC vs. DOHC
09-09-2004, 04:53 PM
#2
4th Gear Member
Join Date: Aug 2004
Location: Southern Kentucky
Posts: 1,487
RE: SOHC vs. DOHC
The SOHC has one cam over each head and only 2 valves per cylinder
the DOHC has 2 cams over each head controlling the 4 valves per cylinder (2 intake 2 exhuast).
The DOHC is just a really really efficient version of the SOHC which is why it makes more power.
The DOHC is the better engine due to its level of efficiency, but you end up paying the $$ for it. The SOHC is capable of making the same ammount of power with the addons out now, but you will spend more money to get there than you would the DOHC. End the end though, if you put a blower on either one, you can turn yourself into an airborne telephone pole missile
.
the DOHC has 2 cams over each head controlling the 4 valves per cylinder (2 intake 2 exhuast).
The DOHC is just a really really efficient version of the SOHC which is why it makes more power.
The DOHC is the better engine due to its level of efficiency, but you end up paying the $$ for it. The SOHC is capable of making the same ammount of power with the addons out now, but you will spend more money to get there than you would the DOHC. End the end though, if you put a blower on either one, you can turn yourself into an airborne telephone pole missile
.
09-11-2004, 12:19 AM
#10
5th Gear Member
Join Date: Mar 2004
Location:
Posts: 4,813
RE: SOHC vs. DOHC
ORIGINAL: dustinpolcz
i asked bc my 2k gt is a sohc and was just curious.
i asked bc my 2k gt is a sohc and was just curious.
the DOHC with 4 valves per cylinder can flow more air in and out of the cylinders because the two smaller valves will outflow 1 larger valve and with space limited by the bore size, using only two valves per cylinder really limits how much flow the heads will do, but making the valves smaller and using 2 of them each for intake and exhaust really steps up the flow potential and horsepower output. it's all basic geometry and areas of circles within circles. if you draw a 4" circle and then draw one big intake valve and one smaller exhaust valve and calculate the flow areas of each circle then draw another circle with 2 intake valves and two smaller exhaust valves and calculate the flow areas you will see how much more flow area is there with the 4 valve setup. I don't know the actual valve sizes or I would do the math for you and show you the difference.