What should my cam idle at?
For mild cams, an idle ignition timing advance of approximately 16-18 degrees will do. For medium cams, try within the range of 18-22 degrees of advance. Wild, lumpy cams may require 24-30 degrees depending on the compression ratio, cylinder head port sizes, etc.
Which is better hydraulic or solid lifters?
Solid lifter cams can be a good choice for a hot street or race engine. They usually have faster ramps (lobes) than hydraulic cams, but not as fast as roller cams. They also need stouter springs than a hydraulic cam, but not nearly as stiff as a roller cam.
What is a good idling RPM for a small engine?
Idle speed is probably in the 1500 rpm area, with max rpm around 3000-3500. Idle speed won’t change with the pulley, but it might be harder to start unless it has electric start. That small a pulley shouldn’t affect the motor much at all unless there is a load on that pulley.
Why do big cams cause low vacuum?
As the lift gets greater on a normal tappet cam, the ramp has to extend further around the lobe. This invariably increases the overlap that the intake and exhaust valves are both open. This caused less vacuum at idle, but helps pull in the intake charge at high rpm when the exhaust is being scavenged.
What should rpm be at 70 mph?
70mph = 2413rpm. how do you know your exact rpm?
What should my rpm be at 50 mph?
What should my rpm be at 50 mph? 1500 rpms for 50 mph sounds about right. your overdrive works.
What makes a cam choppy?
LSA (lobe separation angle) determines the choppiness, it has to do with the overlap of when both valves are open, as in when the exhaust valve is closing and the intake valve is opening to pull fresh fuel in on the intake stroke after pushing out the burnt fuel. Most GM cams come on a 112, 114 or 116 LSA.
What is Cam surge?
Cam surge is something you get with aftermarket camshafts and improper computer tuning. It cause the car to buck under 2000rpm. Its most noticable in an M6 car in first gear at around 10mph, like when going through a parking lot.
Does a bigger cam affect vacuum?
The longer lobe durations are combined with more overlap to use the effect of scavenging to actually pull the air/fuel charge into the combustion chambers. Together, those qualities in a camshaft harm the amount of vacuum any engine will pull in the intake manifold plenum.