4AGZE Cam timing, its got me stumped!

[Rick]

I have been building a new motor for my car, everything has been going together pretty well so far apart from the new cams that I have installed, they are second hand after market cams and came with a cam spec sheet, but I cannot for the life of me get the cam timing lining up with the spec sheet, either the cams are not what they are ment to be or I am doing something wrong, I have tried many times and different method but alas I am not getting anywhere.

Is there anyone that is competent in 4AG/ZE Cam timing (willing to pay) or know of a workshop in Auckland that can do the work?

[Stu-]

Give Brendan at Convert Motorsport / Nite Parts a call

[jondee86]

... or I am doing something wrong, I have tried many times and different
method but alas I am not getting anywhere.

Can't say for certain looking at your pic, but it sure looks like you have
both knock pins in the same slot. If the cams are supplied with the knock
pins in the factory location (so that they can be used with factory cam
wheels), then you need to set them up with the inlet at 12 o'clock (near
enough) and the exhaust at 5 o'clock (near enough). Like so...



Cheers... jondee86

[Crucible]

Disregard where the cam gears are located for now..

To get the cams sitting in the right position you want the crank at tdc and No4 Inlet and Exhaust cam lobes rocking on the valves. So exhaust has just closed and inlet is about to open, inlet lobe pointing to exh manifold and exh lobe pointing to inlet manifold, Exhaust to Inlet transition.

This will mean No1 In and Ex are on the back of the cam lobes (both valves fully closed) ie clearance between valves and cams, Compression to power stroke transition.

This sets the cams in correct time with the crank, Now see where the pulleys sit. Marks should be straight up (with factory pulleys anyway). The adjustable ones should sit, have marks or dots pointing to backplate marks also, Should be able to dial them into specs from there.