Help with cam timing

[fivepointhustla]

Is there a degree or measure per tooth on the cam sprocket?

I want to retard my cam 8 degrees and am trying to do it without a degree wheel.

Is there a general rule of thumb like 2* per tooth or something like that?

This on a 3.1 iron head

[bszopi]

On the 3100, each tooth is 7.2º. Its actually quite each to figure it out... Simple math tells you to count the number of each, divide that into 360º, and what do you know... degrees/tooth.

[rickykline]

why do you want to retard the cam 8* from stock?

[fivepointhustla]

I have a comp 260 and it is advanced 4* I run juice so I have no need for a super torquey cam. I like the cam but the powerband is 1-5k I want 2-6k or as close as possible.

[geoffinbc]

Duration is going to affect the RPM range the most. More so than the intake closing event, which is the key event you are trying to alter when adjusting your cam timing.

I am sure you already know that a 270 cam would better suit your needs but I was just stating for other peoples benefit.

So follow Brads math advice for timing adjustments. But also know that altering your cam 8* is alot and you should consider what you are doing to the timing of the other valve events versus piston location. You may be screwing it up more that you are improving it.

[rickykline]

yeah 8* could mean a battle between the valves and pistons..

[fivepointhustla]

I only want 4* retard as the end result. Does that matter? I mean if my timing gear has the same amount of teeth as the 3100 and I happened to install it wrong with 1 tooth retard then I can't see that being a problem.

[CNCguy]

It is early for me but wouldn't that be 7.2º at the cam which would be 14.4º at the crank?

[SappySE107]

Thats what brad and I are working on with this template deal. When you degree the cam, thats crank degrees right? I have the timing wheel on the crank and came up with 113.5 ICL and I want 108. So I would need 5.5 crank degrees or cam degrees? If its 5.5 crank degrees, then I want 2.75 cam degrees?

[CNCguy]

Thats what brad and I are working on with this template deal. When you degree the cam, thats crank degrees right? I have the timing wheel on the crank and came up with 113.5 ICL and I want 108. So I would need 5.5 crank degrees or cam degrees? If its 5.5 crank degrees, then I want 2.75 cam degrees?

It can be confusing at times since all events are measured in lift at the cam, degrees at the crank and there is a 2:1 gear ratio. You would need to change it 2.75 at the cam.


On a different note, I am having a few sets of TC cover spacers made and they should be finished next week. They are made from 1/8" thick stainless and each set includes spacers for the TCC, dampner and FWD right head to move the ALT. These should allow the use of a double row TC but do not address the issue of AC comp location. Doesn't the DRTC setup have provisions for timing adjustment?

[SappySE107]

Yes it does, but only in +-4 degree. We don't get the really nice setups but it would still be better than stock. Thanks for the update. I don't know if I have enough time for that on this motor but I really hope so. I want it for my 3500 though so send me a set as soon as you get them done

There is still 1 problem with the double roller setup. I will take some pics here in a bit.

[SappySE107]

http://60degreev6.com/gallery/browseimages.php?c=35

[Arns85GT]

I'm not running boost or juice, and I have the GM HO cam. I'm considering advancing the cam 4* to lower my power band from 4200 - 5800 down to 3500 - 5200.

If you have a cam with built in 4* advance, and you retard it 8* are you not going to rob your bottom end quite a bit and raise your power band alot?

Arn

[fivepointhustla]

That is kinda what I want

[fivepointhustla]

How do you post screen shots?