What is valve timing and how it affects engine performance?
What is valve timing and how it affects engine performance?
Engine valve timing is the most critical process of IC engines. Engine Valve Timing Diagram The inlet valve usually opens few degrees before the piston reaches TDC in its exhaust stroke. It closes after quite a few degrees of piston reaching the BDC, i.e. when the piston starts to move up the cylinder in the compression stroke.
When to delete variable valve timing ( VVT )?
Eliminating the VVT system is required when swapping to a non-VVT camshaft. These cams offer higher valve lift and longer duration for more performance. A VVT delete kit removes the VVT components and replaces them with standard parts. At a minimum, they include:
What is the timing of the inlet valve?
The timing of the opening & closing of valves is specified in degrees corresponding to the position of engine’s pistons. Engine valve timing is the most critical process of IC engines. The inlet valve usually opens few degrees before the piston reaches TDC in its exhaust stroke.
How does oil pressure change the timing of the valve?
The engine computer on these engines can command a hydraulic actuator to send oil pressure to the VVT gear at the end of a camshaft. The oil pressure causes the camshaft to change position in relation to the cam gear, effectively changing cam (or valve) timing on-the-fly.
What does GM’s variable valve timing do to the engine?
Twisting pretty much describes what GM is doing with its camshafts today. Valve timing improvements used to be accomplished via camshaft lift, duration and lobe separation. Those values were set in stone once the engine was assembled and were strictly the province of engine designers and performance enthusiasts. Not so with variable cam timing.
Are there pushrod engines with variable valve timing?
Pushrod engines, as of the 2007 model year, are no longer confined to the set-in-stone mode of cam timing, either. Look for full-size trucks, SUVs with V8s, along with Corvettes and the all-new 2010 Chevy Camaro to start appearing in your bays soon sporting variable cam timing on their single-cam-in-block engines.
Eliminating the VVT system is required when swapping to a non-VVT camshaft. These cams offer higher valve lift and longer duration for more performance. A VVT delete kit removes the VVT components and replaces them with standard parts. At a minimum, they include:
What does a LS timing cover look like?
They only have a three-pin connector for the camshaft sensor. These are two LS engine timing covers. The one on the left has the camshaft phasing actuator, indicating that it is from an engine with VVT. The one one the right has no actuator, so it is from an engine without VVT.
