Cam Timing

[Guest clive5550]

hi all, im after some help ive been trying to time my engine when ive got the engine at tdc where should the woodruff key be on the cam ?, i have a adjustable pulley wheel on a piper cam and the wheels got no marks on it ive timed mine with the key at the very bottom of the camshaft and the two lobes on number 1 pointing up but its running ok on tick over but undriveable underload cutting out and popping back through carbs ive tried everything please someone help and does anyone know the nearest rolling road to ipswich please.

[richardm6994]

You need to set it according to your inlet valve on cylinder 1 at full lift. But to get this figure you need to know what cam you've got.

 

i.e Kent fr32....the inlet valve is fully open when the crank is 108 degree after top dead

[Guest clive5550]

thanks for reply its got a piper cam on it, does a standard pulley wheel fit on that way i could make sure the marks line up

[IanS]

After market cam manufacturers deliberatly do not use the same key location to make you buy a vernier cam pulley.

It is posible to make an offset wodruff key to get the valve timing correct. You do need to know the timing that piper designed the cam for and then measure what the nearest timing is that you can get with the normal key so as to know how much offset to machine into the new key.

[Guest craig38]

Hi set number 1 piston at true tdc with a dti gauge and then put a timeing disk on the crank pully and assuming its a piper 285 go 108deg past tdc,and then find full lift on number 1 inlet valve with dti gauge a vernier pully is for fine adjustment be carefull of piston to valve contact hth craig

[Guest clive5550]

hi all thanks for replys, yes its a piper 285 and they are saying set it at 108 deg past tdc ive got head off at the moment had a bit of water pressures problems ! if i set the crank at 108 degrees past tdc and make sure no1 inlet is fully open when i bolt it all back down it should be right or am i missing something ive marked crank pulley at 108 degrees to make things easier