Please help me with degreeing a camshaft.

[Brandon Sinclair]

I don't do this too often so it always becomes a nightmare for me.

Here are the specs according to the cam card:
Web 86B
lobe center 108 degrees
duration at .050" 260 degrees
valve timing is to be checked with zero valve lash @ .050" of valve lift
IO 22BTDC
IC 58ABDC
EO 58BBDC
EC 22ATDC

Here are my numbers at .050" of lift at the valve:

IO 28BTDC
IC 63ABDC
EO 62BBDC
EC 27ATDC

Where does that leave me...advanced or retarded and by how much?

Thanks

[modnrod]

Looking at the numbers you've posted compared to the cam chart.....
Inlet is opening 5.5degrees earlier than the cam cards numbers.
Exhaust is opening 4.5degrees earlier than the cam card numbers.

Let's just say we'll split the difference, and average it out to you having the cam dialled in at 5 degrees advanced as you are now.
 

[Brandon Sinclair]

If I enter my figures into the degree calculator on webcamshafts.com I get this info...

Overlap: 55.00 degrees
Intake Duration: 271.00 degrees
Exhaust Duration: 269.00 degrees
Intake Installed Centerline of 107.50 degrees ATDC.
Exhaust Installed Centerline of 107.50 degrees BTDC.

I am not sure on how changing the cam buttons and retarding the cam timing further would alter the duration figures I believe it is built into the camshaft.  According to the camcard the duration is supposed to be 260, but mine is coming out at 271 and 269 degrees with 55 degrees of overlap.

Maybe it has to do with trying to take the readings at the valve (retainer) according to the cam card while Engle and SLR say taking their readings at the tappet. 

Funny on the webcamshafts website it indicates that you can either take the reading at the tappet or the valve but they recommend at the valve for pushrod engines.

I am confused.  It is late and I need some sleep.

[modnrod]

I am confused.  It is late and I need some sleep.

Obviously it would seem I was too. I looked at the IVO and EVO but didn't look properly at the closing points, so I got it wrong.
I screwed it up, I'm very sorry to cause any further confusion.

The data from Web Cams is correct, it looks 108* installed.

Just a quick note about the duration. You are checking the cam with no lash at the valve, which is probably where the extra 10* is coming from.

[Taylor]

You can't check it at the valve and expect to get an accurate run down.  Check it at the lifter cup and see the difference the rocker making.

[Brandon Sinclair]

I am going home to check at the lifter instead of the valve and will report back with my readings.

In fact I am going to verify TDC on the pulley again for the #1 piston and go from there.

It is strange that the cam card indicates that the numbers are .050" at the valve.

I called Webcamshafts and they said that theirs are lift at the valve with zero lash.  Looking at my numbers they said it sounded like I had an 86c since the figures I have are almost right on with a 86c.

I am going to take more readings right now to see what I come up with.

[Fasteddie63]

What Taylor Said,Check It At The Lifter

[Taylor]

I'm not saying Web said the valve or the lifter but they would also have to tell you what rocker they use to get the numbers.  It's a small amount but a 1.1, 1.25, 1.3, 1.4, 1.5 berg 1.54, they will all get to. 050" at different degrees.

[Brandon Sinclair]

I tried to explain that to the Webcamshaft rep, and her answer was not the most reassuring.

I told her I am using CB rockers which are supposed to spec at 1.4, but the cam card indicates 1.5 rockers so wouldn't that change the numbers.

I will let you know what the measurements are at the lifter.

Thanks

[Taylor]

Also, another thing about checking at the valve, although minimal @ .050" the Pushrod deflection will skew the results.   Unless a checking spring in used.

[Brandon Sinclair]

Thanks for the info Taylor.  Yes, I was not using check springs so deflection can definately be a factor.

Here are the readings I am getting at the lifter:
IO 22 BTDC
IC 57 ABDC
EO 57 BBDC
EC 21 ATDC

Both lifts at the #1 ex and intake lifters spec out at .379" which is in line with an 86B camshaft.

Here is what the cam card indicates the numbers should be:
IO 22 BTDC
IC 58 ABDC
EO 58 BBDC
EC 22 ATDC

[Taylor]

So we are going to call that 1' advanced!  when you checked it at the lifter did you stick the indicator into the lifter cup?  I cut about  2" off an old pushrod and tapped the end for a socket head bolt.  I like to have a pushrod end inside the lifter with oil for checking.

[andy198712]

i asked about lift with the 86B, this is what webcam said

The cam lift is .385 we have it calculated with a 1.5 rocker in our catalog, however can be used with a 1.4, specs are as follows:
.385 x 1.4 = .539
.385 x 1.5 = .577.5
Thanks

[JIMP]

I'm wondering, why you are trying to see the angles at every stage after the card instead of just verify -after you're 101% sure that you have a correct tdc on the pulley or your degreeing wheel- that your lobe centers are at 108o -or even slightly advanced like 106o- You could do this actually for both inlet and exhaust, if you have like 108o and 108o at inlet and exhaust respectively or 106o and 110o you're set right imo.Anyway if the other angles don't get you anywhere you can't do much, this is how the cam was cut so that's it. And as the others said already, try to stick to the lifter side not the valve side, just my thoughts

Friendly

Dimitrios

[Shag55]

Agreed, events must be checked at the lifter. There are to many variables at the retainer.
1* advanced or retarded will have very little difference in your case.