lmfao good explaination jafart bwhahaha

I'd go out on a limb here, but using adjustable cam gears on a 4V would allow you to tune the intake and exhaust valve timing independently, especially with aftermarket cams where the powerband is higher in the RPMs

Jason

The original reason for dohc (e.g., the classic Jaguar XKE six) was that it allowed opposed valves. Opposed valves (e.g., Chrysler hemis) flow better than side-by-side (wedge) valves or splayed (Rat, Lima, or Cleveland) valves. A sohc can be rigged up for opposed valves (e.g., the Mercedes 3-valve sohc heads), but the long rockers required for this design negate a large part of the ohc advantage over the cam-in-block: lower valvetrain weight.

In a 4-valve head, opposed valves are not optional, they're required. That's why 4-valve heads are always (or nearly always) dohc.

As far as flexibility, you're right that a variable valve timing setup that only advances or retards the cam would have greater flexibility with a dohc setup. But there are sohc vvt setups, too. Some regulate valve timing by varying the oil pressure to the lifters; some use two rockers following different cam lobes, also hydraulically actuated. These setups also allow different valve events on the exhaust side than on the intake side.

Regardless of the valvetrain, you can always grind one cam lobe for the exhaust and one for the intake. These are called "dual pattern" cams and are very common in the aftermarket for pushrod V8's. The ability to grind a different lobe for the exhaust than for the intake is unaffected by the location or number of the cams.

lmfao would throw a MIL lite on pretty fast limp mode here we go the sender is usually camshaft lmfao

hurc ast