Engine Types?

[Sage]

What does pushrod, DOHC, and SOHC mean? (I know they're types of engines, but that's all I know)

 

[troy]

Dual Over Head Cams, Single Over Head Cams (SOHC is a guess, but i am positive about DOHC

 

[Sage]

Erm... what does it all mean?

[edit]: Performance wise, etc.

 

[MazKid]

Duel Over Head Cams= 2 cams per cilynder above the cilynders.

Single Over Head Cams= 1 cam per cilynder above the cilynder.

Pushrod is just another name for a piston engine...

 

[vat_man]

These things are methods of operating the valves, which sit above the piston in the top of the combustion chamber (or cylinder). Inlet valves let petrol in, exhaust valves let exhaust gasses out.

A good summary can be found here: http://www.howstuffworks.com/camshaft2.htm

 

[Sage]

Thanks!

 

[Deathhawk]

Pushrods are not just another name for a pison engine.

Typically they are called CIB motors (cam in block) They use connecting rods (pushrods) to actuate rockerarm to in turn open and close the valves. They are typically in older 4cylander US motors or curren (some) V8 american motors.

A CIB motor can't rev as high as eiter a SOHC or DOHC motor because the connecting rods tend to bend and break at high rotational speeds. I think I read somewhere that they can be run to around 10000RPM where DOHC in F1 cars are running 19000RPM easily.

 

[Mad Medic]

Your explaination is correct but the names are wrong. Push rods are just that- push rods. Connecting rods are the part that join pistons to the crankshaft. The reason that push rod engine can't rev as high as overhead cam engines, is because of the higher number of moving parts. You have a cam, a lifter, a push rod, a rocker arm, and finally the valve. The overhead cam engine has the cam, sometimes a lifter, and the valve. G.M. and Ford have both produced an overhead cam engine which were very successful engines; Ford's SOHC 427, and G.M.'s Corvette big block which was partially designed by Mercury marine in the late 90's.