Degree an installed/unknown camshaft

[Wietse]

The crank gear has 3 slots but spread over the diameter.
Not sure what to do with that.
I could retard the cam 1 or 2 teeth if i wanted to though.

 

[miller]

I could retard the cam 1 or 2 teeth if i wanted to though.

No. Not something you want to do. You could get valves kissin' the pistons.
The 3 slot crank gear (guys correct me if I'm wrong!) allows straight up, -4 degrees, or +4 degrees.

3 hits only, for each cylinder. Results are good 'average' compression readings. If those readings are right, looks good/average for a 440.

 

[wyrmrider]

put it in on the straight up position? right?
cam is most likely already ground with 4 degrees advance
still too much compression (where's AJ when we need him) go to the -4 and retry
think you need more low end and have some compression headroom go +4
that will not fix vacuum as you have not changed overlap
but closing 4 degrees earlier on the intake will give you an idea on how an 8 degree shorter cam will affect low end and compression
downside is that exhaust is opened 4 degrees earlier which heats up the EGT and cuts your power stroke and fuel mileage
(this is more of an effect on a low compression motor)
One reason to have all 4 valve events in the right place with a custom cam
now we are trying to figure out where or if you are OK as is.
you can buy a lot of gas for the price of a cam change
so run it for awhile
as Miller said do not even think of retarding a tooth
history
back with our 265 chevy wagon pure stocker we did retard a tooth then advance 4 degrees
really low gears and wound the snot out of it
no low end at all but more power shift to shift
came off the line near valve float
then they started allowing "cheater" cams

 

[Wietse]

Currently the camshaft is already advanced 1 tooth right?
If the dot on the crank sprocket is at the 12 o'clock position the cam sprocket dot has already passed.
How much degree does 1 tooth make? How many teeth on the cam gear?
At the other key way it looks like there is a little triangle instead of a "0".

To get this camshaft straight up, i should set it back 1 tooth right? Or am i mistaken?
I don't get it, to retard it 1 tooth back to the "straight up" position i could smash the valves with the piston, but advance or retard 4 deg by using the other key way slots can be done?
You cannot tell for sure how much valve clearance is remaining i guess...specially with 0.570" valve lift.

 

[AJ/FormS]

Ok, so when cranking 3-4 times i get 150-155 PSI.
When continue cranking until it the gauge will no longer increase i am gettin 175-185 PSI. (2-3 stroke pulses but no longer increasing)

The most correct numbers are the; crank-until-she-hits-two-consecutive-same/nearsame numbers. If gets there on 4 then that's all you need to crank. If it takes 8 or 10 then that's what it takes.
NEVER pre-oil the cylinders, this will artificially increase the numbers.
Never crank with gas-washed cylinders; thus will artificially lower the numbers.
This is the primary reason we do a compression test on a recently-run engine. It will have just the right amount of oil on it. This is also why the test is done at WOT; the numbers come up a hair faster and there is less chance of gas-wash.

So it looks like the new numbers are averaging 180, whereas the earlier numbers, IIRC were about 197. No matter, 180psi is still too high to swap to a smaller cam.

 

[AJ/FormS]

Comments in the quote

If it really had detonation it would have been a goner already i guess because i have been driving it over 800-1000 miles with the current setup.That kindof depends on the type of driving,and the quality of the parts installed
Only carb was changed recently.
But yeah, how to identity detonation, the only thing i can hear when the vacuum advance was connected is this tingling sound in the exhaust, sounds like there are some little stones inside rattling on the pipe. Was that at idle, part-throttle/part load or full-load-WOT?

And am close to sea level indeed, actually my town is probably at -1 meter below sea level That's kindof what I remembered from grade school; you know tulips,windmills, dikes, reclaimed land, and wooden clogs.

So the cold cranking compression is something to work with? Yes
It has not run for several weeks now so piston rings and liner will be "dry" of oil by now. Not so, there will be enough for the compression test and beyond.

@wyrmrider:
The cam seems 1 tooth advanced as in the pictures, when crankshaft sprocket is facing up the cam gear dot has moved along 1 tooth.
Chain has little slack but i guess not excessive.
I assumed the dots on the gears alway line up at the cyl #1 @compression stroke, Not exactly at, just near
that's why i figured how it is possible to be off but indeed it can be at any location really. Not any,lol. But yes one tooth out in either direction, and it will still run.
In the pic,to me, the crank-dot does not appear to be truly vertically in line, on the imaginary line that runs directly through the centers of both the crank and the cam. Tell me I'm wrong. But if it has rotated just a tiny bit past TDC, in the CW direction, then the cam dot will also have rotated too far in the CW direction. But, visually, the crank-dot moves to the right while the cam-dot moves left.
But I agree, the cam-timing appears off.
No matter, cuz degreeing it will tell the tale.


View attachment 819711

 

[AJ/FormS]

Mr. Wallace says
OK but first I have to qualify this; the Scr numbers were chosen to generate your preassure numbers,with the assumption that your cam is correctly installed at 4* advanced! If your cam is over-advanced to generate your cylinder pressures, then NONE of the following illustrations will be correct. Rephrased, that is to say; ALL of the following will be wrong.
So, Mr Wallace says;
in a stock boreNstroke 440, to make 196psi, you need an Scr of 12/1;
Static compression ratio of 12.0:1.
Ica of 68* @sealevel
Effective stroke is 2.80 inches.
Your dynamic compression ratio is 9.21:1 .
Your dynamic cranking pressure is ................................ 196.37 PSI.
V/P (Volume to Pressure Index) is 193

here it is with cam retarded 4*, from theoretically 4* advanced
Static compression ratio of 12:1.
Ica of 72*, sealevel
Effective stroke is 2.69 inches.
Your dynamic compression ratio is 8.89:1 .
Your dynamic cranking pressure is ............................... 187.60 PSI.
V/P (Volume to Pressure Index) is 178
Do not make the mistake of thinking your combo will do this because your combo may be over advanced as it is.

And to make 180 or so, requires 11.2
Static compression ratio of 11.2:1.
Effective stroke is 2.80 inches.
Your dynamic compression ratio is 8.62:1 .
Your dynamic cranking pressure is ............................... 180.25 PSI.
V/P (Volume to Pressure Index) is 178

But what you need, for your 95gas is about
Static compression ratio of 10:1.
Effective stroke is 2.80 inches.
Your dynamic compression ratio is 7.72:1 .
Your dynamic cranking pressure is ................................ 156.09 PSI.
V/P (Volume to Pressure Index) is 154

With a tight-Q design AND YR's compression expertise, you might get away with
Static compression ratio of 10.7:1.
Effective stroke is 2.80 inches.
Your dynamic compression ratio is 8.24:1 .
Your dynamic cranking pressure is .................................169.98 PSI.
V/P (Volume to Pressure Index) is 167

AND with the addition of Wyrmrider's cam experience, you might be able to get away with
Static compression ratio of 10.3:1.
Swap out that 68*Ica for next smaller 64*Ica
Effective stroke is 2.91 inches.
Your dynamic compression ratio is 8.22:1 .
Your dynamic cranking pressure is .................................169.45 PSI.
V/P (Volume to Pressure Index) is 173

At least on our (R+M)/2 gasoline you might.

Please notice the downward progression of the VP. Firstly with the current cam and it's Theoretical install of Ica=68, beginning at 193 and ending at 167. Which is still a excellent street VP.
Then notice that the next smaller cam at slightly less Scr, increases the VP to 173, which for an SBM is to die for.
VPs over 140 are a lotta fun, by 150 the tires and chassis have more or less given up.
I'm currently at 152VP with my 367, and wouldn't wish for more; it's ridiculously overpowering my 68 Barracuda; but is also ridiculously much fun.

Ok now, go back to the opening statement and reread it; then
lets suppose your cam is over advanced 8* from where it's supposed to be. It is supposed to be at about 4* advanced putting the Ica at 68*.
So let's install it at 60* and readjust the pressure to 180psi, and see what the Scr comes to. And I get;

Static compression ratio of 10.5:1.
Ica of 60* @sealevel
Effective stroke is 3.01 inches.
Your dynamic compression ratio is 8.63:1 .
Your dynamic cranking pressure is ............................ 180.52 PSI.
You just measured this as 180ish right
V/P (Volume to Pressure Index) is 191
Notice the Scr is now just 10.5!

Ok so let's assume for a second that this is painting a more accurate picture of your engine combo. This makes sense doesn't it? This is sortof what your timing experiences are pointing to.
OK then if your Scr truly is 10.5, just ponder it. Then lets go with 10.5 and put the cam where it's supposed to be and see what happens.
And I get;

Static compression ratio of 10.5:1.
Ica of 68* @sealevel
Effective stroke is 2.80 inches.
Your dynamic compression ratio is 8.09:1 .
Your dynamic cranking pressure is .............................165.96 PSI.
V/P (Volume to Pressure Index) is 163

How sweet would that be!

So, disconnect the battery. Then unpack your equipment and get busy,lol. If you have to or want to move the cam, don't forget about measuring the PV clearance. As you rotate the crank, you have to do concentrate very hard on feeling resistance when the valve kisses a piston. STOP! Back up: something is wrong. Figure it out.

 

[Wietse]

Wow....i have to read that a few times to let it sink in..
Thx for all the effort spend here to help me out.

So, how do i go to get this cam set at its normal timing?
Just move the cam sprocket 1 tooth back and make sure the dots align when the crank sprocket is at 12 o'clock, correct?
I also need to find out at what slot the key is at the moment, 0, -4 or +4 deg.
The one it is at now shows a "0", i noticed the other indicator at the other key way looked like a triangle shape. Is there a meaning on them?
How much degrees does 1 tooth off give?
You are talking about the ICA (Installed Centerline Angle), how/where does this number come from?

 

[Wietse]

But yeah, how to identity detonation, the only thing i can hear when the vacuum advance was connected is this tingling sound in the exhaust, sounds like there are some little stones inside rattling on the pipe. Was that at idle, part-throttle/part load or full-load-WOT?

I believe with the vac can connected on ported i would get this sound at very light throttle just off idle, and with it connected to manifold it would come at part throttle/part load.

And am close to sea level indeed, actually my town is probably at -1 meter below sea level That's kindof what I remembered from grade school; you know tulips,windmills, dikes, reclaimed land, and wooden clogs.

Yes, you forgot the Heineken beer and marihuana though!

So the cold cranking compression is something to work with? Yes
It has not run for several weeks now so piston rings and liner will be "dry" of oil by now. Not so, there will be enough for the compression test and beyond.

@wyrmrider:
The cam seems 1 tooth advanced as in the pictures, when crankshaft sprocket is facing up the cam gear dot has moved along 1 tooth.
Chain has little slack but i guess not excessive.
I assumed the dots on the gears alway line up at the cyl #1 @compression stroke, Not exactly at, just near
that's why i figured how it is possible to be off but indeed it can be at any location really. Not any,lol. But yes one tooth out in either direction, and it will still run.
In the pic,to me, the crank-dot does not appear to be truly vertically in line, on the imaginary line that runs directly through the centers of both the crank and the cam. Tell me I'm wrong. But if it has rotated just a tiny bit past TDC, in the CW direction, then the cam dot will also have rotated too far in the CW direction. But, visually, the crank-dot moves to the right while the cam-dot moves left.
But I agree, the cam-timing appears off.
No matter, cuz degreeing it will tell the tale.

Lol, i know not "any" location but when the shafts are in sync they could have used any position in the correct timing. Just assumed they are spot on on #1 TDC, but lesson learned!
See this picture, here the crank is at #1 TDC, 360deg later.
I actually should have turned the crank a tiny hair more on this one.
The dot sits now on top but again obviously is already past the top center.
The other picture seems a bit off, guess it is just the angle i was keeping the camera that it seems past the imaginary center line but it was "spot on".

 

[Wietse]

See the pics of the 3 locations for the key way, there are a "0" (where installed now), a triangle and a "D" or reqtangular shaped symbol.

I believe this kit is from Pro-Gear, i cannot find the mentioned numbers online, probably due to these are quite old.
I think the numbers are date codes of manufacturing, which are 1995 and 1999.

Crank sprocket: 109BA-B (9-95)
Cam sprocket: 108K-A (5-99)

I will keep trying to find something, maybe i can say for certain the adjustable degrees, and what indicator stands for what ( "0", +- deg)

EDIT:
Maybe not exact rocket science, but i measured along the shaft circumference the distances between the indicator and centre of key way:

Triangle: 13.5mm
Zero: 15.5mm
Rectangular: 17.5

So it is in the "0" position, so no advance/retard given by the sprocket.
The difference between them is roughly 6* when looking at the circumference of the shaft.
As the cam gear has 50 teeth a single tooth would give 7.2* advance/retard.
So according me it has been advanced 7.2* by moving it 1 tooth.

 

[miller]

Still on coffee, so bear with me...yikes, and stop! And get off the one tooth bit. Except, as the third photo shows, could be a tooth off.
The three markings on the crank gear, as mentioned, 4 degrees +-, straight up. Any one of them, dots would still be in line. I'm pretty sure looking at paperwork for any three slot gear set, the markings would be the same.
Only rely on a degree wheel!!! And, if you had it, the cam card.

I would pull the timing chain, first. Put the gears themselves back in place, and line the dots up, by hand. Then you can get the chain back in place, and go from there...

How much slack is in the chain? Measurement.

 

[Wietse]

The crank gear in that picture is 100% at 12 o'clock position, it is 100% sure the camshaft sprocket is located advanced 1 tooth with the current indicator.
Being wanted, being caused by chain slack, don't know but i know it is off 1 tooth.
Speaking chain slack, with all slack on 1 side i can push/pull it and see around 1/2" of travel, which i think is too much already.
There is no way it will jump a tooth but still seems excessive.

I am pretty sure the "0" mark on the crank sprocket will be the "zero" installation position and the triangle and rectangular shape are +4* and -4*. From what i measured it seems more +6* and -6* but that is very rough measurement and as i've seen normally these wheels have 4* offsets so guess 4 it is.
Also hand cranking it in normal (CW) rotation so it cannot be the slack is on the wrong side causing the misalignment.

So, i should get the sprockets and chain off, set it up with the marks aligned.
I stay with the current "0" key slot on the crank sprocket and reinstall it back.

 

[miller]

So, i should get the sprockets and chain off, set it up with the marks aligned.
I stay with the current "0" key slot on the crank sprocket and reinstall it back.

Yes.

The other guys will tell you true, if I'm off. But, IF the cam already has 4 degrees ground into it, and safe start would be straight up (0) dot to dot. But, you won't know squat, until you toss a degree wheel on it. That's the only way you'll know exactly where your cam events come in. More important on bigger lift cams.

While you have the gear off the cam, look at the front, for any possible #s. Or, trying to figure out what cam it is, find one same as, to look up a cam card. Guessing is great, but might not give you the results you want.

1/2" slack in the chain? Iffy...much variation on your distributor timing? Wait, to see what the other guys, with more experience say on that one.

Any rate, that's what I'd do.

 

[Wietse]

Just went through the manual for correct chain slack measurement procedure.
There it stat 3/16" of movement is the limit, i measure 2/32" on mine so seems ok.

The other guys will tell you true, if I'm off. But, IF the cam already has 4 degrees ground into it, and safe start would be straight up (0) dot to dot. But, you won't know squat, until you toss a degree wheel on it. That's the only way you'll know exactly where your cam events come in. More important on bigger lift cams.

That's how i was thinking, the cam might have an advance ground in it.
But regardless of that, they might have advanced it 1 tooth to reach what they wanted.
Using the 4* advance with the crank sprocket was not enough, maybe therefore they went with 1 tooth off to get 7,2* extra instead of buying another crank sprocket that has multiple degree slots.
(fuckers might have went cheap on this.)

I will set the timing in line (dot to dot), rotate by hand slowly a few times to check if any valve is being hit.
Then i will setup the dial gauge again and check the same valve events at 0.005", 0.050", 0,100" and 0,200" and centerlines.

I am hoping there will be something as part number on the shaft indeed.

 

[Wietse]

Ok...i know... "YOU SHOULD HAVE DONE THAT EARLIER....i know..

So it's a Hughe Engines HE3844 BL camshaft.

I moved the cam sprocket 1 tooth across and let them align at the 12 and 6 o'clock position.
It did not hit anything when rotating but now need to find out how to position it as per the above readings.
I just retarded my figures 7*, from my measured figures at 0.050" i am still around 6* advanced.

 

[AJ/FormS]

Miller has yo covered.
Indeed the the alternate key slots are just there to help you achieve the proper install, without having to resort to special offset keys.

The only measurement that means anything is the installed centerline. All other exercises are done to find the current Installed centerline. Then, if it ain't right,the exercise points you to the direction and amount in which it needs to go. Then you use one of the slots to get you as close as possible. Then you repeat the degreeing exercise to see how close you got. It is generally accepted that if you are within 1 or 2 degrees of the target, you are close enough.

But in your case, with the unusual pressure readings, before buttoning up the front, I would repeat the compression test. If the numbers are still so high, then you might want to retard the cam slightly from the recommended installed centerline. This is not generally done in a streeter because of the loss of pressure, and the attending softness at low rpm. However your case is sprcial; with the BB and the already excessive pressure, your bottom end will get softer that's a fact, but that softness will be a good thing. On account of the tires can't take a VP of over 160 anyway, and it will make finding the optimum ignition timing easier as well. 4* retard in your case , will only move the power peak up about 200rpm.
So then, after correcting the one-tooth-out, all that remains, is to find the resulting installed centerline, and deciding if it needs to be moved.

According to the spec you provided, Hughes wants that cam to be installed at 105 which is 3* advanced.

 

[Wietse]

So, my original measurements @ .050" were as follows:

Exh open: 66* BBDC
Exh closed: 1* BTDC

Int open: 27* BTDC
Int closed: 29* ABDC

Now i moved it to:

Exh open: 59* BBDC
Exh closed: 6* ATDC

Int open: 20* BTDC
Int closed: 36* ABDC

Due to the measurement margins, aka "my ****-ups in measuring" there were differences of 12-15 deg between my original measurement and the cam card specs.
2 of them showed 13* difference, 1 showed 12* difference and 1 showed 15* difference.
So think 13* advance was put on this cam by the builder, i just removed 7* by setting the cam timing sprockets dot-to-sot.
I should get another 4* (or 6*) out of installing the crank sprocket on the other key way, but which one?
According me i should be at the rectangular shaped indicator.
Better check with you guys to prevent going the wrong way and do hit a valve with the piston by accident.

 

[AJ/FormS]

You cannot proceed until the degree-wheel shows repeatable results. Which, with the heads on, can be a chore.
Before I had made the solid lobe follower with flat and parallel faces, Sometimes,I would flip the lifter upside down, to get the indicator out of the pushrod cup. Then you only have the lifter's concave foot to deal with, and you can pretty much take care of that by setting up the indicator tip to be and stay in the center of the upside down lifter.
As for the symbols on the crank gear, I forget which one does what.

 

[Wietse]

Ok, so now is should do a few rounds verifying the valve events as it is currently setup?
I will install the lifter upside down as well, hopefully that will give clearer readings.
At worst seems like i have been off only 1-2*, not bad for a first time measurement....disaster error for a pro but hey, hopefully next round i will come out clean

 

[miller]

Miller has yo covered.

What?? Ya mean I got something right?

You cannot proceed until the degree-wheel shows repeatable results. Which, with the heads on, can be a chore.

Spot on. Bear in mind, as on a fresh engine build, first thing you do once the crank, and cam are installed, the cam degree wheel gets zeroed off the top of the piston.
That's before the heads go on!

Even being a degree, or two off, is fairly common, and doesn't hurt. (Close enough for government work!) Being as accurate as possible, is what makes the difference. I went through 3 complete rounds, of dialing in my Crower, before I was satisfied.