Help. Does anyone put there know the difference between standard camshafts?
Are any of them more sort after than the expensive aftermarket ones?
Is there an advantage fitting an EFI cam to a carb engine? Is the 3.9 EFI a good swop for the 3.5 9.35;1 comp cam?
Dave
Standard camshafts
Moderator: phpBB2 - Administrators
Hi
The differences between the various "standard" cams are fairly small, the EFI cams tend to have a wider lobe seperation angle to give a cleaner exhaust gas reading at idle, this also tends to mean they are "softer" ie the power is right from idle and hangs on a little longer (we are probably talking 150 revs here!) you will probably notice more differance between a new and old timing chain than between one standard cam and another. This only real exception to this is the cam from the Stage 1v8/ 101FC used by landrover, they are designed to work with a restrictor plate in the inlet and limit power to 90 BHP.
Mike
The differences between the various "standard" cams are fairly small, the EFI cams tend to have a wider lobe seperation angle to give a cleaner exhaust gas reading at idle, this also tends to mean they are "softer" ie the power is right from idle and hangs on a little longer (we are probably talking 150 revs here!) you will probably notice more differance between a new and old timing chain than between one standard cam and another. This only real exception to this is the cam from the Stage 1v8/ 101FC used by landrover, they are designed to work with a restrictor plate in the inlet and limit power to 90 BHP.
Mike
poppet valves rule!
Hello Dave,
As Mike said, the differences are slight. There are subtle differences in valve timing between the different factory OEM camshafts...for the 3.5, 3.9 and 4.2 litre engines.
Fitting a 3.9 or 4.2 litre camshaft into a car which previously had a 3.5 litre engine may well improve low to mid range performance, especially if the car is an automatic. The valve timing and duration would no doubt favour better delivery of low speed torque which would be a benefit in such a car, although at the expence of top end performance, say anything over 4750 rpm.
Ron.
As Mike said, the differences are slight. There are subtle differences in valve timing between the different factory OEM camshafts...for the 3.5, 3.9 and 4.2 litre engines.
Fitting a 3.9 or 4.2 litre camshaft into a car which previously had a 3.5 litre engine may well improve low to mid range performance, especially if the car is an automatic. The valve timing and duration would no doubt favour better delivery of low speed torque which would be a benefit in such a car, although at the expence of top end performance, say anything over 4750 rpm.
Ron.
4.6 Rover 3500 P6B
