I just came in from the shop,...frustrated!
I am freshening a 440 that somone else built,and will have it on the dyno in a couple of weeks.
I bought a different camshaft and timing set to go with it,thinking I will see some decent gains with the cam swap.
The old camshaft/timing setup was installed dot to dot,and checked in at 6 degrees advanced which is where it's recommended installed centerline is.
I mocked up the new camshaft/timing set to see where everything needs to be,so it is easier once I get it on the dyno to make a back to back test.

It was 20 degrees retarded when lined up dot to dot!! I had to check my work three times because I could not believe it! Advancing the timing set 8 degrees brought it exactly 8 degrees closer,so now only 12 degrees retarded!
And some people say lining up the dots is close enough??????
ALWAYS check the installed centerline!!! I can't imagine how poorly this would have ran if it was put together that way. I will have to try another timing set and see if the "dot" on the cam gear was in the wrong spot,or if it is the camshaft itself.
Keith

Anything made by us mere mortals can be screwed up or we can screw it up even if we didn't make it.

being 20 degree's off sounds more like your off 1 tooth. advance the cam 1 tooth and you'll have enough to be within the amount the timing set will correct.

When I first built mine 340 the cam key way was off
27*... I did the dot to dot to get a base line and
couldnt understand why the valve was hitting the piston...
the cam worked fine once I degreed it but forget that
dot to dot stuff... like you said I dont know how some
guys do the dot to dot and call it good

Kind of figured they just missed it by a tooth when they marked it,just trying to warn people.
I never run them with just lining up the dots,but you have to start somewhere.

Keith

That's amazing ( if it aint off a tooth ). I always degree in my motors, using the dots as a starting point. Never found one off more than 2 degrees, and most are dead on. Just did my 5th
Hughes cam last week. All were dead nuts on.

I bought my Dart many years ago with a 340 in it. Sounded funny. Cam in one tooth advanced. Ran better straight up!

Yes, always check the cam installed centerline position.
One tooth off on the timing set is about 12-14 degrees.

I have seen cams marked/ground right on, 2,4, and even 9 degrees off from the recommended installed position (typically 4 degrees advanced from LSA). And all those were with the same timing set, block, crank, etc.