Which is more important intake or exhaust cam timing?
Intake cam timing has a much more influence to the torque curve than exhaust cam timing. So usually I do the follow procedere: – Tune the engine roughly and get a feel where the knock treshould is. If possible set the AFR into the middle of the window where the engine makes most power. For turbo engines thats usually between 11.5 and 12.5.
What happens when you change the camshaft timing?
Changing either affects engine performance, but a camshaft that is properly installed in an advanced position can noticeably improve performance. Four-cycle engines perform an intake, compression, power and exhaust stroke in each cycle. Each cycle requires two complete crankshaft revolutions.
How does the camshaft work in a four cycle engine?
Four-cycle engines perform an intake, compression, power and exhaust stroke in each cycle. Each cycle requires two complete crankshaft revolutions. The camshaft, which controls the action of the valves, rotates at half the crankshaft speed. The camshaft controls the movement of the engine valves.
Can you adjust the exhaust cam stepless with VTC?
In your case with VTC you can only adjust the exhaust cam stepless. The inlet cam has only two positions. So you just have to search the right shift point for every exhaust cam setup. That’s an easy one. – After an exhaust cam timing change, make a run with VTC ON over whole rev range and one with VTC OFF.
How does cam timing and Cam separation affect the engine?
The following tables illustrate how variations in lobe separation angle and cam timing will effect the behavior of the engine in which the camshaft is installed.
What is timing procedure for exhaust valve opening?
Exhaust valve opening (EVO) Overhead cam timing can be tricky on some engines. Always refer to the OEM timing procedure so you know how the timing marks are supposed to be aligned. On some engines, you have to count the chain links between sprockets to get the proper alignment.
Where is the timing boss on an exhaust cam?
The square boss on the end of the exhaust cam (“A”) that the arrows are pointing to, should appear to be rotated slightly clockwise from square to the head surface. This is the normal timing position of the exhaust camshaft. The same description of cam positions for bank 1-4 applies to bank 5-8.
What’s the best way to install a camshaft?
1. Prepare a clean work area and assemble the tools needed for the camshaft installation. It is suggested to use an automotive manual to help determine which items must be removed from the engine in order to expose, remove, and reinstall the timing chains, camshaft actuators/phasers, and camshafts.
Intake cam timing has a much more influence to the torque curve than exhaust cam timing. So usually I do the follow procedere: – Tune the engine roughly and get a feel where the knock treshould is. If possible set the AFR into the middle of the window where the engine makes most power. For turbo engines thats usually between 11.5 and 12.5.
In your case with VTC you can only adjust the exhaust cam stepless. The inlet cam has only two positions. So you just have to search the right shift point for every exhaust cam setup. That’s an easy one. – After an exhaust cam timing change, make a run with VTC ON over whole rev range and one with VTC OFF.
What happens when you change cam timing at high RPM?
At high-RPM, this may become a restriction since the air has inertia and responds a little slower to pressure changes, potentially choking the air flow to the engine a little. Conclusion: This information is aimed at allowing tuners to understand what happens when cam timing is altered.
What happens when you install a larger camshaft?
When a larger duration camshaft is being installed, unless the lobe centerlines have been changed, the overlap will be increased. If installing larger camshafts in a turbo application, advancing the exhaust and retarding the intake will reduce the inherent increase in overlap caused by upgrading to a larger profile.