hey now ive wiki'd and googled both of them so i understand the difference but i was wondering how much of a difference theres is performance wise between the two and as far as i have gathered magnas came out with SOHC if that is tru is there any DOHC 6g72/74 engines that can just replace the existing ones magnas have, i am also aware that you can get mivec DOHC's but im not to keen on a flat torque curve

Did you do an AMC search at all?
http://www.aussiemagna.com/forums/search.php?searchid=1019760

There contained will be some information you are after.

i am also aware that you can get mivec DOHC's but im not to keen on a flat torque curve


can i ask why just out of curiousity?



DOHC vs SOHC well dohc are generally more tunable and are tuned so from the factory, it mainly allows one cam to control exhaust valves and one to control air/petrol valves, its hard to get a good hi powered tune on a SOHC because if you modify one aspect of it ie. exhaust lift, in some way the rest will be affected, and at high revs the rotation will be limited that why power is reached earlie and dies of quicker. MIVEC and VTEC and VVT etc all operate on SOHC basis untill it hits the rev mark and the other cams are introduced to there full extent to create quicker rotation, thats why DOHC engine generally can rev higher than SOHC and things like VTEC hit peak at like 7200rpm. thus runing on a SOHC concept the car can get fair enough amount of power low end and when the other two cams are introduced at about 3000-4000rpm, when torque starts to dive off to maintain it and boost it some more. DOHC is also more economical than a SOHC most of the time.

flat torques curve is awesome, just having 230nm of torque at the wheels from 1500rpm is bloody awesome, i'm gone miss my verada.

thats at least what i've come to understand, someone correct me if i'm wrong.

can i ask why just out of curiousity?



DOHC vs SOHC well dohc are generally more tunable and are tuned so from the factory, it mainly allows one cam to control exhaust valves and one to control air/petrol valves, its hard to get a good hi powered tune on a SOHC because if you modify one aspect of it ie. exhaust lift, in some way the rest will be affected, and at high revs the rotation will be limited that why power is reached earlie and dies of quicker. MIVEC and VTEC and VVT etc all operate on SOHC basis untill it hits the rev mark and the other cams are introduced to there full extent to create quicker rotation, thats why DOHC engine generally can rev higher than SOHC and things like VTEC hit peak at like 7200rpm. thus runing on a SOHC concept the car can get fair enough amount of power low end and when the other two cams are introduced at about 3000-4000rpm, when torque starts to dive off to maintain it and boost it some more. DOHC is also more economical than a SOHC most of the time.

flat torques curve is awesome, just having 230nm of torque at the wheels from 1500rpm is bloody awesome, i'm gone miss my verada.

thats at least what i've come to understand, someone correct me if i'm wrong.
Ok... I think you are confusing cam lobes and camshafts. A DOHC is 2 camshafts per bank and SOHC is but 1. A SOHC 24 valve 3 or 3.5 has 3 cam lobes per cylinder with 2 directly acting on the intake valves and 1 operating the exhaust valves via a forked rocker. With some variable valve timing systems they alter the cam timing by advancing or retarding the cam relative to crank position. Some also introduce a seperate lobe that has a more aggressive profile that comes into play at higher RPM.


http://en.wikipedia.org/wiki/Variable_valve_timing

http://en.wikipedia.org/wiki/DOHC#Double_overhead_camshafts

can i ask why just out of curiousity?
flat torques curve is awesome,

i dont no y i drove a friends riced out honda a while ago and it felt slightly unnatural well compared to what im used to but i supose i could get used to one and i can understand the benifit of one

']Did you do an AMC search at all?
http://www.aussiemagna.com/forums/search.php?searchid=1019760

There contained will be some information you are after.

Mmm. Search not work.

Like it has been said, leaving out the vtec/mivec/vvti talk..

DOHC has one cam dedicated to intake and the other exhaust. This means you can make the best intake and exhaust profiles on their own cams rather than having one cam for intake and exhaust and having to compromise on the the intake or exhaust angles..

It's like having running shoes and casual shoes rather than cross-trainers.. well that makes sence to me anyway, each cam can be designed specifically.

Also DOHC engines look way cooler when the cam cover is off.