Degreeing cam...how do I hold the wheel in place...how to make it where I can rotate?

[5spd GT]

Here are the instructions I'm going to use...

http://www.holley.com/HiOctn/TechServ/TechInfo/IECCTech8.html

Thanks...

David

 

[HISSIN50]

i bet Michael gives you a nice long reply. i believe he has covered it before if you are up to searching.

 

[Zombietime]

Here are the instructions I'm going to use...

http://www.holley.com/HiOctn/TechServ/TechInfo/IECCTech8.html

Thanks...

David

In step 10 of those directions "your cam is retarded"

(i know what it means, i just find it still funny after all these years)

 

[tmoss]

After tightening the wheel tight enough to keep it from comming loose, it will probably move a degree or two - no big deal, just recheck it to see which way it's off and add/subtract that amount to the results you take off the cam.

 

[Michael Yount]

If the motor's out of the car, after you've tightened the degree wheel, rotate the engine from the back using one of the flywheel bolts. If the motor's in the car so that you have to use the crank bolt for rotation, the easiest way to not loosen the degree wheel is to only rotate the engine clockwise. For most measurements, you should only rotate clockwise anyway because that's the way the engine turns and any slack in the timing chain will be taken up the same way it would be when the engine's running. If you slightly rotate past where you wanted to, just rotate around 360 and try again. Of course, remove all your spark plugs (if they're in) to make small rotational changes easy. If find that if you get to within a few degrees of the mark, and then just bump the ratchet handle with your hand to ease it to the particular reading your'e after.

 

[5spd GT]

Alright...well I got it were the degree wheel would stay still...

I got a measurment of 30 (clockwise) and 31 (counterclockwise)...so which way do I need to move the wheel (or pointer)...to the left .5 or to the right .5?...this is looking at the degree wheel from the front...

 

[Michael Yount]

I always mark my wheel with a felt tip, and I indicate the direction of rotation for each mark - so when I rotate it up and stops at 30, I draw an arrow in the direction of tdc, and the same thing coming the other way. The two arrows will be pointing at each other - and it's half way in between 30 and 31 in the direction of the arrows. If the head is off the car, simply remove the stop and rotate til the piston is near the top - then find the halfway point between your two marks. Just to be sure - setting the pointer at the calculated halfway point on the wheel is how you find tdc. Seeing the piston at the top confirms it. If you pick the other halfway point the piston will be at bdc - so you can't really screw it up if you check piston location.

 

[5spd GT]

OKAY...PLEASE READ ALL (VERY IMPORTANT STEP )...

This is from the front of the wheel...

I put my dial indicator on the lifter...

(middle) TDC - BTDC (right)

@.050 lift I got a reading of 3* (closer to 4* than 3*...this is to the right of 0*) and my cam car shows open at 5* BTDC...so know what do I do...advance or retard it 2 degrees? do I even need to advance or retard...it is the equivalent of 3.8*...

Also a FYI (don't know if it matters)...but the reading was taken during the exhaust TDC? (not compression stroke)...if that matters? or makes the readings inaccurate...

Also Ed OUTLINED the 107 intake centerline that opens at 5* BTDC

The 109 opens at 3* BTDC as I got (closer to 4* (3.8* actually)...

Is the 3.8* close enough to not advance or retard it or it would be in my best interest to do it...?

Hope that wasn't to confusing...ask me and I'll rephrase myself...

David

 

[Michael Yount]

If you're saying the intake is open .050 at 4 btdc instead of 5 btdc, I'd advance it 2 degrees so it opens at 6 btdc -- moving it a bit in the advance direction will have it right at 5 when the chain gives/stretches a bit with time.