What is the best method to use to degree a cam with asymmetrical lobes?

Maybe I'm not understanding the question, wouldn't matching the valve events @.050 still work?

Follow the mfgs recommendations. You'll get different centerlines depending on where you measure so just follow the instructions. They might tell you to use an 0.050 lift number, or perhaps they'll tell you to use something else. They should know how they want it installed.

BTW - this question sparked a huge debate on the old SpeedTalk board that went on for months. Mike Jones kept telling everyone to shut up and to just follow the mfg instructions but people kept arguing about where the center line is on a non-symmetrical lobe.

Usually take the readings .050 before and after max lift

Use the cam card numbers, all of them of @ .050. then you will know what you have, and if your measurements vary at all.

I asked this question here about 20 years ago when I tried my first street roller which was visibly
very asymmetric just eyeballing it....the answer was do centerline method the same as anything else.

I predict the answer will be the same, and might even come from the same people as back then.

As a sanity check you can work the numbers both @.050 and @.020 before and after max lift to see if it comes out the same.

the safest way is the centerline method, but that doesn't mean the .050" thing won't work. this is time consuming but when i mess with asymmetrical lobes i check seat timing to find out how long the closing ramp is and go from there. centerline method should be fool proof.

My cam card shows open at 30.5 at .050 and I get 29. Cam is installed at 105.25. Closing spec is 58.5 and I get 57 .050 before close. So that is real close. I have a gentleman over on speed talk tell me to use .020 to center the cam with asymmetrical lobes. I am still trying to figure duration at .200 lobe lift. Do I read the wheel for this or is it a math equation? Spec is 190 lobe lift at .200.

Also, bullet says not to use the lifter bore tool for measuring any cam specs. If roller, must use a lifter because of the wheel size. Mine are .810 wheels. Doing this does seem to get more accurate measures.

For duration at 0.200 you just read the numbers on the wheel as you turn the cam from 0.200 to 0.200. When you go past TDC you need to keep track of what you are doing.

Follow your cam card and ignore the guy on Speedtalk telling you to do something else. You have the cam card, use it. If you don't understand the cam card then call the mfg. People on Speedtalk argue with everything and everybody just for fun.

Isnt your cam installed 2 degrees retarded? If so, the @.050 numbers line up close enough. Lifter bore bank angle and plane errors can move the @.050 numbers around quite a bit.

Send it.

Ok, thanks Andy. I will give that a try tomorrow.

You have to degree off of the events not intake center line

Yes, its close. Just need to check v/p clearance. I am now at truely 105* centerlined. The numbers on the card are very close.

104

Uh-huh...couldn't agree more...that fancy looking CompCams tool caused me a massive headache as I attempted to degree my mild hydraulic roller. Eventually, degreeing off of an actual roller lifter got me the matching numbers.

Don't say "don't use lifter bore tool".
There are different lifter bore tools with different diameters.
I machined my own. My "tool" has a 0.810" dia ball on the end. One man's tool is different than another. And Comp's tool might have small balls...

And I use the 0.050" numbers for discussion. But I have measured the centerline at many lobe lifts for info. It can vary. But 2 degrees either way doesn't mean one number is best for your engines combination.

Just went through this. Measured @.050" open and close. Also C/L @ .070", .050", .030" before max lift. None are quite the same. In fact duration was longer than the card showed. The bottom line is advance it further than you'll ever need and check intake P to V. Retard it to far and measure exhaust P to V. Then stab it in close to where you think it should be, by whatever method you chose. Then when it's up and running you can move it with confidence. You'll never no what's best unless you try different spots.
Doug

Yes, i will have to see what my clearances are at my current 105* install and go from there.

It’s okay Charlie....... I know what you’re saying there.

On the other hand, when the VP clearance is marginal....... it may have to be installed wherever it fits.