l bought a vechicle and is says 24 v on the side and they said it has a dual overhead cams what is that for?

Overhead cams eliminate the need for transfers (Valve train) of the Cam motions to either side of the Cylinder heads as each cam is mounted on one of the two heads, and have a very slightly faster action.

24v means three valves for each cylinder instead of the usual two valves per cylinder.

Dual overhead cams means there are two camshafts per cylinder head, one for the intake and one for the exhaust. A V6 with dual overhead cams would have a total of 4 camshafts.
24 valves means 4 valves per cylinder on a V6. Two intake valves and two exhaust valves. 4 valves times 6 cylinders makes for a total of 24 valves.

Dual over head cams means that the cams r in the cylinder head. One operates the intake valves & the other operates the exhaust valves. This is more efficient than a push rod engine where the cam is in the center of the block & push rods have to push rocker arms that actuate the valve. In an over head valve engine the came pushes directly on the valve & there is less power loss due to less friction. Divide the number of valves (24) by the number of cylinders & that is how many valves per cyl. Usually the more valves the better. If there is an odd number of valves per cylinder, for the most part, there r more intake valves than exaust valves.

older cars had one or a main camshaft, many of todays cars have two smaller camshafts mounted above the engine instead of below or on the bottom.

The camshafts open & close the valves that let the fresh air in & the exhaust out of the engine.


Generally, engines with dual overhead camshafts (DOHC) r higher performance engines, they produce more power, & can run at higher speeds.

The main benefit of dual overhead cams is that they allow an engine to have four valves per cylinder.

Each camshaft operates two of the valves, one camshaft handles the intake valves, & one handles the exhaust valves.

By having four valves in a cylinder instead of two, a larger portion of the area can be used to let air in & exhaust out. The engine can make more power if more air enters the cylinder, & it wastes less power if it is easier to pump the exhaust out of the cylinder.

engine has 4 camshafts, with 4 valves per cylinder, older cars had 1 camshaft and 2 valves per cylinder