Could I get other knowledgable GMI folks to weigh in on this? Which design typically uses more parts, and and which is more costly?
SOHC and pushrod engines use about the same amount of parts on V-engines. The pushrod V6 has 12 pushrods, the SOHC engine has one more timing bely, an extra cam, a few extra cam sprokets, larger heads, and some other stuff I am forgetting, like larger lubricarion system to feed that extra crap.
Cost is about the same, but so is power output going by displacement.
DOHC engines throw in a lot more valves, cams, their driving gear, rocker arms and THEIR little pieces, MUCH bigger heads and lubrication systems, yadda yadda yadda.
They produce more power for their displacement, but are also MUCH larger for their displacement. The 3.5 liter Nissan V6 is nearly identical in size and weight to the 7 liter C5R engine. The 3.9 V6 will be about the same size and weight as the S2000s 2/2.2 liter I4 if it goes aluminum.
Displacement is a terrible way to compare engines anyway. It isn't the volume of air that matters, it is the amount of air and how it flows that matters. You can have 2 molecules of air in a liter, or you can have a billion molecules of air in a liter.
In short, here is why I prefer pushrods:
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SOHC and pushrod engines use about the same amount of parts on V-engines. The pushrod V6 has 12 pushrods, the SOHC engine has one more timing bely, an extra cam, a few extra cam sprokets, larger heads, and some other stuff I am forgetting, like larger lubricarion system to feed that extra crap.
Cost is about the same, but so is power output going by displacement.
DOHC engines throw in a lot more valves, cams, their driving gear, rocker arms and THEIR little pieces, MUCH bigger heads and lubrication systems, yadda yadda yadda.
They produce more power for their displacement, but are also MUCH larger for their displacement. The 3.5 liter Nissan V6 is nearly identical in size and weight to the 7 liter C5R engine. The 3.9 V6 will be about the same size and weight as the S2000s 2/2.2 liter I4 if it goes aluminum.
Displacement is a terrible way to compare engines anyway. It isn't the volume of air that matters, it is the amount of air and how it flows that matters. You can have 2 molecules of air in a liter, or you can have a billion molecules of air in a liter.
In short, here is why I prefer pushrods:
