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Hi guys have a question on the first ever motor i did a timing chain job on.

so i have a 1972 pontiac 350. i installed a timing set on it and the only one availbale at the time when i was doing the job was an edelbrock double roller chain set.

so this being my first time i didnt realize the the 3 key way slots on the crack gear were or -4, 0 or +4 degrees if timing. now im not so sure which position i put it in. the car starts up and drives fine, i have it timed at 14 degrees and it idles good. there is a slight stumble if i go full throttle but im not sure if its a carb issue with my edelbrock.

so my question is how do i find out if it is advanced, retarded or at 0 degrees without taking the cover off? at the time i had a garage, now we rent a house and our landlord would not be ok with me having the front of the motor taken apart in his driveway. is there any test i can preform

many thanks
 

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You would have to degree the cam , and it would be more trouble than a teardown because that engine is easy to get the timing cover off.
If you know what cam you have you can check the duration (degree the cam) against the advertised duration to see if it is advanced or not. However with the possibility of error at the damper timing mark, and tolerances in machining of the cam that is in it, and the fact that checking the advertised duration is tough as you will be checking on top of a valve retainer as the engine is assembled, and there could be substantial movement of the cam before the valve starts to move , skewing the measurement.
Short of putting on a degree wheel, using a piston stop to zero it, and checking the lift there isnt much of a way to know without a teardown.

the margin of error could be as large as the 4 degrees error that you are trying to identify , by degreeing it, and if youre not familiar with the process, it could be a lot of frustration and wasted time.
 
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