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Discussion Starter · #341 · (Edited)
MORE BS - where does this all come from????? Argh!

Ignition timing ONLY has to do with when the spark plug lights. The distributor may be driven by the cam gear BUT, the distributor rotates freely and can be rotated in any position to set the timing wherever you want, regardless of whether the cam is advanced, retarded or straight-up. Just because they share the same word of "timing" doesn't mean they are referring to the same MEANING of what "timing" is.


I know exactly what you're saying. My builder is just saying that whether the cam design is advanced or retarded, then the spark advance may need to be set differently for best performance.
 

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Discussion Starter · #342 ·
I'm pretty sure that the paperwork that comes with the Comp Cams also indicate a 4 degree advance on their Pontiac grinds. That's what I remember from when I put my engine together. Based on communication from the builder, it sounds like the cam was installed this way. Depending on the timing set, you can select a bunch of options for advancing or retarding the valve timing. Now the question is was it set just 4 degrees retarded from the straight up position or 8 degrees off from straight up to make it 4 degrees retarded. I'm not an expert on this but this could be the reason for lower than expected vacuum.
My paperwork doesn't show 4 degrees. It only says specs are for the cam installed at 106 Intake Center Line.
Not sure how that correlates to 4 degrees.
 

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Discussion Starter · #347 ·
I'm almost back to the point where this whole thread started. Frustrated that I can't find the problem and stuck between my lack of knowledge and tools and taking it back to the builder who I don't want to deal with.

Although with everyone's help here I am able to do a whole lot more than when I started. And together we found and fixed a MAJOR problem.

I would have never thought I'd be adjusting the valve lash with the engine running and valve covers off. Not to mention adjusting the toe-in, installing a fuel regulator, and replacing the turn signal switch.

You all have been GREAT. I've also learned a lot from searching and reading the forums too so it hasn't just been this one huge thread teaching me.

I just need to keep plugging away. Several car shows coming up. Maybe I can find resources there too. Maybe even someone who will see what it's doing and know right off what's wrong. :)
 

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I'm almost back to the point where this whole thread started. Frustrated that I can't find the problem and stuck between my lack of knowledge and tools and taking it back to the builder who I don't want to deal with.

Although with everyone's help here I am able to do a whole lot more than when I started. And together we found and fixed a MAJOR problem.

I would have never thought I'd be adjusting the valve lash with the engine running and valve covers off. Not to mention adjusting the toe-in, installing a fuel regulator, and replacing the turn signal switch.

You all have been GREAT. I've also learned a lot from searching and reading the forums too so it hasn't just been this one huge thread teaching me.

I just need to keep plugging away. Several car shows coming up. Maybe I can find resources there too. Maybe even someone who will see what it's doing and know right off what's wrong. :)
If you can install a turn signal switch, you can do anything lol.;)
 

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This IS a great forum and I've learned so much and still learn something almost everyday. So do you think the builder would fix the cam problem seeing all this information or is he going to say I didn't install the cam wrong I just did it a different way? You could take him for a ride and ask "do think this is right" a car with that motor can't make it up a hill. And all this time he thought the carb was the problem...doesn't sound like it now. Maybe it's time for a little break like was suggested before but don't give up, these smart guys here got your back...I'm just not one of them....yet 👍
 

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Discussion Starter · #356 ·
I think the next step is to clarify with the builder that the cam was installed correctly, dot to dot, and that his statement "the cam is retarded" is merely him referring to what he believed was built into the cam.
I think you are right.
I will have to get the contact information of the engine builder. I don't think my builder really knows any more than the cam part number from CompCams.
 

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Cameo Ivory 1967
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So do you think the builder would fix the cam problem
We havent determined that theres a cam problem. There's a lot of information flying around here and it's easy to go down a deep rabbit hole. As I said early on, lets pull out the splinter before we decide to amputate.
 

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Cameo Ivory 1967
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I think you are right.
I will have to get the contact information of the engine builder. I don't think my builder really knows any more than the cam part number from CompCams.
As Jim mentioned, cam manufacturers build timing into the cam and then state that on the card/ instructions. This is easy to confuse and easily misunderstood.

There are three guys on this forum right now, trying to run dizzys on the street, without vac advance cans, and chasing their tales because their cars dont run right... This is definitely a case of where the internet is not our friend.

This is not the time for old wives tales and hearsay, it's time to systematically check each part of the equation until the error is revealed, That will determine the repair.

Picking up a wrench without first having all of the appropriate data, test results, and planning, is just asking for a lot of big problems.
 

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Cameo Ivory 1967
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So would using a piston stop to find true TDC shed any light on his cam position?
I suppose that's a round about way. The piston at TDC should put the timing mark at zero. The cam couldve been degreed? It's hard to imagine that anyone with the skill to degree a cam, would install rockers without verifying clearance.
 
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