Cam degreeing help me understand!

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dartfreak75

dartfreak75

Restore it, Dont part it!
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Ok started on degreeing my cam this morning and im no where close I have done it over and over and over... and keep getting the same results so I think I'm doing in constant. I used lunatis instructions they are straight forward find TDC rotate until you get .050 valve lift on the number 1 intake and compare it to the card. That's where my trouble comes in. My cam card says 2 degrees BTDC. I'm getting nothing btdc my dial is still at zero up until I im past tbc! At .05 lift im 22 degrees ATDC! I don't understand what im doing wrong i don't think the came is off 180 because then the lobe would be on the other side wouldn't it? Thanks i appreciate your input

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I follow this guy on Youtube. THere are a lot of how to degree videos.
 
When you started, where were the positions of the marks on the cam and crank sprocket? 6 on the cam and 12 on the crank? If so, that's tdc compression stroke for #6, not #1.
 
RammerJammer75 said:
When you started, where were the positions of the marks on the cam and crank sprocket? 6 on the cam and 12 on the crank? If so, that's tdc compression stroke for #6, not #1.
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Yes I set it up 6 and 12 and turned it over to 12 and 12 to be on the 1 compression
 
RammerJammer75 said:
Did you verify TDC with a dial indicator? Just trying to go thought the steps with you to see if we can find a problem. I don't know if I've ever seen a timing set 24* off before. I guess it could happen though.
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Yea I set TDC and double checked it i could understand 2 or 3 degrees but 24! I don't get it.
 
Just in case yall see something I don't here is the timing chain when I first installed it. The last one was after I turned it over to #1 compression

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Maybe off one tooth? I don't think so but maybe I'm wrong?
 
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'Looks' okay, but the symptom sounds like the sprockets are a tooth off with that much....try advancing the cam one tooth and see how it comes out. Easy test. It's not common, but if they mark that cam sprocket just a little bit off...it screws you up. It's happened.
What I like to do is lay the timing set on be table first, line up the dots and then move the cam sprocket one tooth in either direction, to make sure the dots are in their best alignment position. Then I take a sharpie or something like that and make another mark closer to the edge so that once it goes on the engine there's no chance of misaligning it.
 
Another thing to check, just in case... Make sure the dial indicator plunger hasn't run out of travel, and the plunger or your lifter aren't hanging up a little.
 
You shoud be right the way you have it set now using the single keyway lower sprocket, kind of like a factory setup.

Using multiple keyway lower gears multiplies the chances of getting it wrong, so you have to degree it to make sure it is correct, and not 4° retarded as such.
 
Im using one of those printed degree wheels off the interwebs is it possible it could be off that much?
 
Im seriously thinking im just doing it wrong but i cant figure out what id be doing that wrong!
 
A thought comes to mind........are you on an intake lobe or an exhaust?
 
I see nothing wrong with the pictures. I would challenge the process of the degree wheel.
 
George Jets said:
Here is the factory correct setting firing on number one cylinder.

View attachment 1715619923
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Yep that's what mine looks like. My way of thinking it shouldn't matter either way where you start as long as the dots line up. The crank makes 2 full rotations to one cam rotation so no matter where you start 12 and 6 or 12 and 12 the cam timing will be the same. Once you crank the crank over the cam goes with it so eventually you will get back to number one
 
How are you trying to find TDC? Use a piston stop. That's the best, most positive way.
 
What I would just to see if you are even in the ballpark is roll the engine to TDC firing, and then rotate it 180 degrees so you are on overlap.

Then look at the lifters. If the exhaust lifter is higher than the intake, the cam is retarded. If both lifters are the same height the cam is installed split overlap, or straight up. If the intake is higher, the cam is advanced.

Also, I’m not sure what you have the dial indicator riding on, but I would find an old pushrod or something and cut it off above deck level and get the DI up away from the block like that.

The other thing is I look at the intake centerline first. Once that is correct, I verify what then at .050 number is.

Cam timing is simply doing nothing more that putting the cam in the correct location relative to the crank.

I care way more where the cam is at max lift than I do what’s happening at .050. They should both match the cam card, but lifter bank angle anomalies can affect that .050 opening number.

Some guys were themselves over that number. Some guys claim their lobes are so different that the ICL doesn’t matter. It does matter.
 
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