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Question on degreeing cams

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Hi Andre,

So I've looked at the webinar and the question I have is, if you are installing aftermarket cams into an engine along with vernier adjustable cam gears and your intention is to go on the dyno when completed and tune the engine, then why do we need to spend the time before and degree the cam as you showed in the webinar? If there is little to no chance of valve to piston contact, then why can't we just put the cams in with the manufacturers timing marks (we know this will not be optimum) but then we use the feedback from our dyno to set the cam to where we want. Is there anything wrong with this?

This is a technique that's often used by tuners. It can be effective so i certainly can't say you 'can't' do it like this. The problem is that you have no idea where the cams are dialled in initially and they may end up miles off the recommended spec. This can have you waste a lot of time on the dyno trying to get back to a baseline. Then there is also the problem of valve to piston contact with larger cam profiles. If you don't know where the cams are dialled in to start with, it's hard to know how much you can move the cam with safety.

Understood Andre, thanks for the response.

Hello Andre,

My question is if you degree a piston to find true TDC using a degree wheel, when it comes to degreeing a cam shouldn't the new measurement for the piston TDC be a factor? or would you still be using the 0 degree TDC mark on the degree wheel?

Sorry, could you clarify your question?

Piston TDC is always THE datum point - what everything is measured from and there is no 'new' as it is what it is.

HI William, finding true TDC is always the first step when you've fitted a degree wheel to your engine. This aligns the '0' point on the degree wheel with the point where the engine is actually at TDC on #1 cylinder. As Gord mentions above, this then becomes the datum point for setting your cam timing.