Would one of you experts verify my numbers please. My small brain always makes me second guess this. Also this should reinforce the do not "just line up the dots" theory.

Installed new regrind of an old cam in my sons Dart. Lined up my marks and proceeded to degree cam. Checking the at .050 numbers I was about 17 degrees off at both numbers. Double and triple check. Scratch head
So I decided to do the other method by checking the intake centerline and I came up with 92 degrees when it should have been 110 degrees. Way to far advanced. So I pulled the cam sprocket and retarded it 1 tooth which should be about 9.5 degrees (according to this site). Do my recheck and I came up at 106 degrees, when the card says 110. This is 4 degrees advance and that is where I planned to leave it. Do I have my thinker on straight? Thanks for the help.

This was the Erson .510 / 246 @ .050 / with a 110 LSA


Rick

Looking at Erson's off the shelf grinds most of their cams are ground 4° advanced so you're likely in the right spot, but if it were mine I would advance it to 102° on the intake centerline for more low end. You checked the #1 intake lobe and not the exhaust correct?

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Joshua

Yes Josh,

I did check the Intake valve. As a matter of fact I just came in from checking the numbers at .050 and they were both real close to 4 degrees advanced. Opening was 4 and the closing was 3. Thanks for the recommendations as well. If I go to 102 isn't that 8 degrees advanced? Most folks on here have recommended going about 4 degrees so I figured I was right on the money.

PS. This is going to be an occasional driver and the low end is not going to be a big deal to my son. The car is a 4barrel, headers, big valve head, 4-speed with 4:30 rear and OD. Any other recommendations are appreciated.

Rick

with those gears i would stay with the 106degs.

Thanks Terry

Based on my experiments on an almost identical cam, I wouldn't use over 102 deg. 106 will give you a lot of top end and not much mid/bottom. Maybe try it there and see how you like it. Terry is right that the gears will help you out up top.

Lou

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Home of Slant6-powered fun machines since 1988

Lou,

I tried to get them to do the LSA on a 106 or 108 degrees but they said the used cam would not allow for that when they checked it. So would you still try the 102 or leave it at 106 where it is. I was planning to button it up after Christmas, but I still have the wheel mounted so it can be changed without too much trouble. He would like some mid-range pull I sure.


Thanks,
Rick

Merry Christmas to all !!

You may want to remove the top (cam) gear and oblong the dowel pin hole .020 to .030 in the clockwise direction, to give yourself a couple of additional degrees of advance. (104 C/L)
Use the side of a 1/4 drill bit and some "in-out" strokes or a small rotory "burr" to make some room for the cam's dowel pin to move more clockwise, in relation to the gear.

Stick a shim (flattened piece of wire or ??) into the space on the backside of the dowel pin and cover it with the hold down bolt / washer.
I have successfully shifted the cam 2-3 degrees, using this simple method.
DD

Doc,

I have enough offset bushings to get it to 102 if I need that. Lou is recommending 102 and I'm at 106. Just not sure what's best. It sounds like you would head for 102 or 104 also?


Thanks,
Rick

Merry Christmas !!

if your son goal is to get max performance, et`s, then with an o.d. trans (3.09 first gear) and 4.30 out back, you will have lots of low end grunt. which means you need less advance in the cam timing , more straight up , so the top end will be there for a better top end charge and more mph.

If you are already set-up to use the bushings, then it is easy to try a different setting.
As for which setting is "best"... we are talking about personal preference at this point. I tend to like milder cams with more low end and mid range power, especially if the vehicle sees some street use. Others like to feel an engine that keeps pulling in the higher RPMs and to be honest, that is how you are going to get max HP from a small engine, keep it making power as you spin it higher.
DD