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Degreeing a camshaft, problems

Odmark91

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Hello! Im trying to degree the camshaft in My 426 and about to loose My mind. I understand its not really possible to help over a forum but maybe someone has experienced similar issues and can give me some tip on what im doing wrong.

The cam is a Hughes Whiplash, installed centerline should be 102°.
Intake timing @0.50":
Open: 13° BTC
Close: 38° ATC

When i set the timing chain "Dot to dot", ofc with the engine at true tdc. I get around 106.5° centerline every time i do it and whatever procedure i use.

So reasonably i should advance it 4° to get it to around 102° right?
Problem is, every time i advance it i end Up with 96.5°, wich shouldnt really be possible?

Also at 0.50" lift im dead on the 13° like the cam card says, but on 0.50" when the lifter is going down im at 26.5° instead of 38. This sounds very odd as well?

When i retard i get around 110.5°, wich also reasonable and matches if i add 4° to the original 106.5.

Any input is welcome, i have put like 15 hours on this this week and is Still on Square One.
 
Are you forgetting that the cam rotates half the amount of the crankshaft?
 
Hello! Im trying to degree the camshaft in My 426 and about to loose My mind. I understand its not really possible to help over a forum but maybe someone has experienced similar issues and can give me some tip on what im doing wrong.

The cam is a Hughes Whiplash, installed centerline should be 102°.
Intake timing @0.50":
Open: 13° BTC
Close: 38° ATC

When i set the timing chain "Dot to dot", ofc with the engine at true tdc. I get around 106.5° centerline every time i do it and whatever procedure i use.

So reasonably i should advance it 4° to get it to around 102° right?
Problem is, every time i advance it i end Up with 96.5°, wich shouldnt really be possible?

Also at 0.50" lift im dead on the 13° like the cam card says, but on 0.50" when the lifter is going down im at 26.5° instead of 38. This sounds very odd as well?

When i retard i get around 110.5°, wich also reasonable and matches if i add 4° to the original 106.5.

Any input is welcome, i have put like 15 hours on this this week and is Still on Square One.

Do you have any photos of what you are doing? Degree wheel, timing set, dial indicator.
 
Did you find TDC with the heads off and a "Dead Stop" on the deck???
You can't go by factory dots. It's very important to do this! Don't get
aggrivated, Stop & have a Beer. (Or Two!)
 
I have 2 questions -
Is it a 426 Wedge or a Hemi ?
Either way, are you checking it on the intake lobe ?
 
Don Frelier: No sir

INTMD8: not right now, but i can take some pictures tomorrow.

zyzzyx: yes i have used a Piston stop to determine true TDC. I have had beer stops all week but sadly it doesent help this time :drinks:

w.Hudson: It is a 426 Wedge, and yes im checking it on the intake lobe.
 
What are you using to advance/retard the cam?
 
What are you using to advance/retard the cam?

And to go along with that...... if the timing events don’t match the card, how are you determining where the cam is actually installed.
You can’t go by one event, like the IO point.

The first thing I do after zeroing out the pointer and degree wheel it to measure the cam lift and duration, to make sure it’s at least close to the cam card.

In your case, your IC point doesn’t match for the cam to be [email protected](13+180+38).

I’d start over, with that as the first step.
Line up the dots...... carefully check the IO and IC closing points....... and see what the actual [email protected] is.
Take that figure, divide by two, subtract IO point....... that’s the theoretical C/L.

Also at 0.50" lift im dead on the 13° like the cam card says, but on 0.50" when the lifter is going down im at 26.5° instead of 38. This sounds very odd as well?

You need to be very sure of the IO and IC points. They determine the true duration.
If your figures are correct......13+180+26.5, then the duration comes up way short........it’s 219.5.
Again, assuming your measurements/figures are correct....... it’s installed at 96.75.

An easy way to verify if these measurements for the C/L are even close......
Check the cam position by the “centerline” method.

Find peak lobe lift.....then back up past .050 from peak lift.
Then, going in the forward direction...... get to exactly .050 before peak lift. Read the degree wheel in degrees atdc.
Keep rotating past peak lift, and when you’re on the other side...... at exactly.050 down from peak lift...... take another reading on the wheel...... also in degrees atdc.
Add the two readings together, divide by two.

For an unsymmetrical cam, this number will usually differ from the open/close method by 1-2 degrees.

After you’ve done the intake lobe, and without moving the degree wheel or pointer....... do the EO & EC points for the exhaust lobe as well, to verify the lift/duration........and then you can calculate the lsa.
 
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^^^^^Best instructions I’ve seen. Thanks!

I’ve chased similar issues. I finally decided it was in the crank gear. You can only do this the same way so many times before you feel like your losing your mind.
 
I'm Dyslexic so when I'm trying to read what you are going through, I get through the first few
words and then it turns to "Blah Blah Blah, Blah Blah Blah Blah Blah"! I can do it with my eyes closed
but have to be sitting in front of the engine with no one bothering me!
 
Stanton: Im using the crank gear to advance/retard, it has different keyways.

PRHeads: Thank you! I will give it another go tonight. I have done it by the centerline method multiple times as well but end up with similar numbers.
 
I just did it by the centerline method and Guess what i got? 96.5 :BangHead:

Could there be something wrong with the cam? Feels like the duration is way off, and that isnt really adjustable is it? It clearly closing to soon.
 
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Feels like the duration is way off, and that isnt really adjustable is it? It clearly closing to soon.

If the duration numbers are way short, then the cam is ground wrong, or it’s just the wrong cam...... or you’re measuring it wrong...... period.

If you’re sure you’re measurements are correct..... time to call the cam supplier.

This is why it’s the first thing I do after setting up the wheel and pointer.
Sounds to me like you have the wrong cam.

You should measure an exhaust lobe as well.

I just did it by the centerline method and Guess what i got? 96.5

Based on your IO/IC points I told you it was in at 96.75.
You just confirmed that’s correct with the C/L method.

The main problem appears to be the duration doesn’t match the specs.

Based on only the intake duration figures, a normal-ish set of events for that lobe for .050 lift would be IO@5 BTDC/[email protected] ABDC.
Depending on where you really wanted it, and what the exhaust events work out to be(which along with the intake events would determine the lsa).
 
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Is there no part number engraved/stamped somewhere to identify the cam?
To get the events matching can be a struggle, i also had my battle to get the readings fall in place and can be a real pain, but the total duration normally would always be very very close which seems not the case on yours so a wrong delivered cam seems likely.
 
If you measure intake and exhaust lobe lift, that would help towards identification .
 
I’m going to ask the dumb question, since I didn’t see anything mentioned about it......

On the Hughes site it shows the Whiplash cam is a hyd roller.
You are degreeing the cam using a hyd roller lifter(not some flat tappet lifter)...... correct??
 
PRHeads, all good posts. I was trying to get around some of these questions by seeing some photos of what's going on :)
 
Had another “dumb question” thought......

The cam is being degreed using a lifter with a wheel...... and you’re measuring “at the cam”?
Not out at the valve with the full spring load collapsing the plunger on the hydraulic lifter?

Degreeing the cam needs to be done using a lifter of the correct type(flat or roller).
And, if you’re going to try and do it out at the valve with full spring load, you either need to be using a solid lifter, or completely bottom out the hyd lifter.
 
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I am using a hydraulic lifter yes, and measuring directly at the lifter. I have no heads on the engine.

I have decided to pull the engine out of the car and do some bottom end work putting ARP bolts in the rods and suchs since i already dissasembled so much and still was going to take the transmission down to put in a McLeod clutch. The only extra wrenching is the hood and one engine mount.

I will try to degree it once more when its out and the bottom end is reassembled, its easier to get correct readings when you dont have to lean over the front. I will get back to you then with new numbers and some pictures.
 
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