Degreeing a Cam vs. Lining Up the Dots

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longarm said:
What I meant to say was each cam will be ground a little different
and it should have a card specific to that cam.
That's not how I've found it to be unless a custom grind.
If you get her zero'd in it will pay in spades.
I'd also check the balancer and housing pointer for TDC, mark the hub and ring
on the balancer, dizzy height and run a bronze gear on the
diz shaft if you can.
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I did check the balancer, it is "reconditioned" the machine shop furnished (my original was about to go). I found it off about seven degrees and remarked the balancer.
 
hi, ok when you line up the dots , cam dot down,crank dot up, you are on # 6 TDC, not # 1 !!!!! rotate the crank untill both dots are at the top, now you are on # 1 TDC. now you can degree the cam correctly!!!if you look down at the cam with dots lined up, the# 1 int lobe and exh lobes are both up, which means you're on # 1 overlap. # 6 will show both lobes facing down,which is TDC!!! after both dots are at the 12 o'clock , you will find the cam will degree in correctly. this applies to mopar , gm , amc engines.
 
perfacar said:
hi, ok when you line up the dots , cam dot down,crank dot up, you are on # 6 TDC, not # 1 !!!!! rotate the crank untill both dots are at the top, now you are on # 1 TDC. now you can degree the cam correctly!!!if you look down at the cam with dots lined up, the# 1 int lobe and exh lobes are both up, which means you're on # 1 overlap. # 6 will show both lobes facing down,which is TDC!!! after both dots are at the 12 o'clock , you will find the cam will degree in correctly. this applies to mopar , gm , amc engines.
Click to expand...

Then why does Cloyes instructions have you line them up like this?
 

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The piston don't care what tdc it is on, the cam decide which on it is on.

With the dots point at each other it just easier to see.

Rotate the crank 360* and now your on #1 compression stroke dot facing up.
 
clifftt said:
Ok, here you go:
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To me, the "open-close" numbers don' t add up, assuming you measure them at .050". I think these numbers are measured at some other lift measurement, like .006" or something. I think I'll sit back and wait until they re-open next week.
You guys are great, I appreciate all your ideas, experiences, and inputs. Thank you!
 

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If you install the gears with the dots facing each other, be sure your distributor rotor is facing the firewall and not the #1 cyl when it goes in.
 
cam manufacturers used all kinds of @ numbers, .050, .006, etc. MP used some crazy formula but most nowadays use .050. I am suprised your damper was 7 off. thats huge but good catch. My Mazda had different colored links that you line up with the dots. pretty ingenious and when they were lined up at crank TDC, the cam key pointed straight up. Wish they could all be that logical.
 
What the guys are saying about timing marks is correct. With the marks together, it's no6 ready to fire, not no1.
 
They are not @0.050 number, they are seat to seat numbers. Looks like its ground on 110 LCA. you can also degree it in using the lobe center method.
 
That sure is a tiny baby *** solid cam. Why in the world did you go with that?
 
Bakerlite said:
They are not @0.050 number, they are seat to seat numbers. Looks like its ground on 110 LCA. you can also degree it in using the lobe center method.
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How can you tell that cam is ground on a 110 LCA?

Even if it is seat to set number, that sheet of paper still shows 0 overlap......yes? no?

Educate me.
 
OK maybe i have figured this out on my own

Intake opens 22.5 BTDC, int close 62.5 ATDC, rotates up to tdc and fires, ex opens at 62.5 BBDC and close 22.5 ATDC.

Over lap would be be 45 degrees.(22.5 before to 22.5 after tdc) sound about right for a small cam like that.

Them matching ## just through me off.
 
I think your right on the money,
they did not add the extra info so
you would definitely have to measure
to find the centerline.
Probably so they could be sure it was
installed correctly.
 
You go Kevin!

swinger340 said:
My x bro in law installed a Mopar performance .508 in a 340 dot to dot. Biggest dog you ever did see. Ended up being close to 16 degrees retarded. After everyone messed w it i straightened it out. I knew something was up when it only had 110 psi in ea cylinder
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RustyRatRod said:
That sure is a tiny baby *** solid cam. Why in the world did you go with that?
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I wanted to run a cam close to the stock 4bbl cam. The numbers are (supposed to be) a little bigger than that. This a weekend driver, Rusty, no race horse that you might build. Love your avatar, always makes me look!
 
I think you might have the events a little off and I think my math is sound...
It's a small cam so I don't think it's opening during the exhaust stroke. If that's the case & using these numbers: intake opens 22.5 ATDC, int close 62.5 ABDC
exhaust opens at 62.5 BBDC and close 22.5 ATDC

Doing the math on the intake stroke: 180 - 22.5 = 157.5
157.5 + 62.5 = 220 / 2 = 110°
On the exh stroke: 62.5 + 180 + 22.5 = 265 / 2 = 132.5°

overlap is 0.
 
lil red said:
...moper...you never cease to impress me...just sayin....
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Moper must have an MBS in Math. Got a chance to do some wine tasting in the Wine Country today. I think the intake opens BTDC. I'll recheck it tonight when I get back.
 
RustyRatRod said:
That sure is a tiny baby *** solid cam. Why in the world did you go with that?
Click to expand...

OK, to momentarily change the subject, with a statement like that, and as our driver is going from one winery to the next, I'm pondering what cam you would use. Basically stock Formula S Barracuda, 4 speed, stock 3.23 Sure Grip, fun to drive, don't plan on racing it.
 
moper said:
I think you might have the events a little off and I think my math is sound...
It's a small cam so I don't think it's opening during the exhaust stroke. If that's the case & using these numbers: intake opens 22.5 ATDC, int close 62.5 ABDC
exhaust opens at 62.5 BBDC and close 22.5 ATDC

Doing the math on the intake stroke: 180 - 22.5 = 157.5
157.5 + 62.5 = 220 / 2 = 110°
On the exh stroke: 62.5 + 180 + 22.5 = 265 / 2 = 132.5°

overlap is 0.
Click to expand...

Intake open 22.5 btdc exhaust closes 22.5 atdc so it 45 degrees overlap
advertised duration would be 22.5 + 180+ 62.5 =265 degrees
 
Without an Intake centerline number your opening/closing events won't be useable without the "at .050 or .006" numbers.

I would wait and ask them, the duration at .050" MAY be what they use on all the degree numbers, but I would not guess.
 
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