Rollmaster questions...
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TECH Apprentice
Joined: Aug 2003
Posts: 335
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From: Vacaville, CA
Rollmaster questions... I put my rollmaster on yesterday and timed the cam with it, but I'm kinda confused as to whether I did it right or not. My cam has +3 ground in, so I wanted to retard it 2 degrees. There are 9 keyways: std timing (has a dot on it) then 2 - 4 - 6 - 8 adv and 2 - 4 - 6 - 8 rtd. It said the keys to the right of std are retard and the keys to the left of std are advance. I used the first key right of standard timing. I slid the crank sprocket on with the key in that keyway. Then I lined up the dots on the cam sprocket and crank sprocket. Is this right? Just use whatever keyway you want for how you want to time it, then line up the dots? That's what I did, I hope its right. Thanks for the input.
Joined: Nov 2001
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From: Texas and Qatar
No, if you advance or retard the camshaft, the original timing mark will not be right. You will need to make a new dot. Rollmasters instructions aren't clear on that. Basically every keyway you move the lower timing gear, you have to move the new timing mark about 2 teeth. The easiest way to do this is to put #1 cylinder piston at actual TDC and make a new TDC mark on your lower timing gear. If you need me to walk you through it by phone just PM me your number. 
If you use anything other than the advance that is ground into the cam then it is NOT "DOT to DOT" regardless if you go to the advance side or the retard side. 2 degrees is a very small amount when it comes to actual crankshaft rotation. You may want to draw yourself an illustration on paper to depict which keyway in the crank sprocket you intend to use and the keyway in the crankshaft to show where they line up. You will still keep the DOT on the cam at 6 o'clock. If the cam remains stationary then retarding crank has the effect of advancing the cam and vice versa. Just be sure that the crankshaft keyway has only moved a VERY small distance from its' factory DOT to DOT postion regardless of whether you go advance or retard.
Thread Starter
TECH Apprentice
Joined: Aug 2003
Posts: 335
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From: Vacaville, CA
Thanks guys. I realized that after I posted. I put it in the 2* retard keyway (1st to the right) and lined it up dot to dot and #1 was already on the way down. It was ALOT retarded. So then I turned the crank sprocket 2 teeth back counterclockwise and it looked alot better. Again, Joseph, thanks for getting things done with my parts.
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Joined: Aug 2002
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From: Ohio
Your playing with fire here. I would use a dial indicator and a degree wheel to install the cam correctly at 2 degrees retarded. Sure you may be able to get by using other methods. But what if you dont. The motor can spin over fine with a wrench even if you are off a tooth or two. but at 6500 rpm you may be looking at some bent valves, or worse messed up head even shatter a piston
Just my .02
Just my .02
TECH Veteran
Joined: Aug 2002
Posts: 4,055
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From: Hartsdale, NY
My first LS1 cam install with the Rollmaster double chain was striaght up and I just aligned the dots - it worked great. I used a smallish cam, however but I check it by rotating the engine a few times.
If I every do another install, however, I will definatley use a degree wheel and dial indicator and I will clay the valve clearences.... too many here have reported disasterous results from shortcuts that have gone terribly wrong...
"penny wise and pound (Euro?) foolish..."
I thought it is very common for cam manufacturors to grind in 3 percent; why do you want to install this at a different rate of advance?
If I every do another install, however, I will definatley use a degree wheel and dial indicator and I will clay the valve clearences.... too many here have reported disasterous results from shortcuts that have gone terribly wrong...
"penny wise and pound (Euro?) foolish..."
I thought it is very common for cam manufacturors to grind in 3 percent; why do you want to install this at a different rate of advance?
