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Cam data help

How to Degree a Cam

Discussion and questions related to the course How to Degree a Cam


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hi. I just watched the how to dial a camshaft course Very good and makes complete sense to me. However my cams are from a pretty big supplier in the UK however they don’t give the data for the way you recommend to dial cams.

I have attached my camshaft data BD14 is the cams I have. What would you do in this situation ?

Also I have hydraulic lifters. I can make a solid lifter from an old one if I need to. However if I fit a solid lifter and then dial the cams. What it is the best way to then mark the positioning as I will then have to remove the cams to remove the 2 solid lifters “in and ex” the engine is a Cosworth YB engine.

Alternitivly should I just buy a set of solid lifters and run these. Only issue there is my cams are profiled for hydraulic as you can see in the data. I know as you said in the video that you can run hydraulic cams on solid lifters but will I get the full benifit ? And what would I set the lash too as there is no data for this that I can see.

Also would you recommend a digital dti gauge or mechanical like your using in the video. And lastly where can I buy the extensions for the dti gauge and the positive lock as I can’t find them for sale anywhere. Thanks.

Attached Files

Anybody ?

If there were adjustable cam pulleys available for your engine, I would install that along with the camshaft. Use common sense in the initial setup (perhaps verify piston-to-valve clearance with a mechanical lifter), or use whatever procedue is recommended by the cam provider. I would mark the cam position with a mechanical scratch on a non-contact part that lines up with something on the head. To make this clearer, you could use machinst blue (ie.dychem) or a sharpie, this scratch through that coating.

With the engine fully assembled, you could just dial in the cam on the dyno for where you want to have the power peak.

I should have said. I have verniers on there and the cams timmed up as per standard engine. I then dialled the camshafts In as per the sheet “115 degrees inlet and 110 degrees exhaust” however I have hydraulic lifters. Bucket type so the camshaft sits directly on top of the lifter and the lifter is directly on top of the valve. So in my eyes the lifter will always be in direct contact with the camshaft lobe. Even if the hydraulic part of the lifter bleeds and the valve moved under the lifter the top part where I am measuring from will always be in direct contact with the camshaft. Or am I wrong here ?

Why is the forum so quite ?

I don't really understand the concern. Is there an installation procedure you got from the manufacturer? Did it not answer any of your concerns? Is the factory service manual not useful? Does the manufacturer not have any kind of technical support? You're not getting much of a response partly because those Cosworth engines were never sold in the US as far as I know. Were they sold in Australia/NZ? I've never even seen one before. I don't know what the valvetrain actuation is like. Do you have any diagrams of it? So there are rocker arms with hydraulic lash adjusters? Does it just look like something like a 4G63 Evo engine head?

If you see the attached cam data sheet you will understand what I am asking. And why I have asked it.

The type of valve train is as pictured. I also described what it is like above. The Cosworth YB engine is known all around the world!! Ford Sierra and escort cosworths where huge in rally and motorsport.

I have attached a photo too.

My setup is different to what is in this course and so I want to know if my type of engine can be dialled in with hydraulic lifters. As the measurement is direct from the lifter not the valve! No no rockers. The data provided does not allow me to dial in the camshafts as per the course “ I believe” hence this post to ask what would be done if anyone else was in my situation. Thanks

Attached Files

If it were me, I'd just go with solid lifters. You should still try to talk to the vendor who sold you the cams though.

That’s the way I am going to go. Think it will be for the best.

Sorry for the slow reply Luke. While it's prone to introducing a small error, an alternative method of degreeing the cams is to use the centreline method. in this instance I'd plot a point 0.5 mm from peak lift on each side of the peak lift point. Once you have these two data points, your cam centreline should be exactly in between. The problem with this method is that it can introduce a small error with asymmetric cam grinds. If you're going to test the cam timing and optimise it further on a dyno then this is really no issue.

As for the solid vs hydraulic lifter situation, you'll find it very difficult to use any of the cam degreeing methods with a hydraulic lifter as they tend to bleed down which will make it impossible to get consistent results. You can swap to solid lifters but as discussed in the course, the cam grind is different for solid and hydraulic lifters so generally a hydraulic cam won't be compatible with solid lifters. I'd just make/fit a solid lifter temporarily for the purposes of degreeing your cams then refit the hydraulic lifters. I will note that solid lifters are often better suited to race engines and high rpm operation.