Cam DOT to DOT half a tooth off. Is that ok?
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Teching In
Joined: Apr 2007
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From: Los Angeles
Cam DOT to DOT half a tooth off. Is that ok? 
Cam is half a tooth off on an LQ9. Is this close enough to be ok? I'm having trouble rotating the engine because I'm building in without a engine stand.
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Joined: Dec 2017
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Yes, that looks right.
The 1st pic has the cam sprocket one tooth off, in the retarded direction. (no I'm not talking about mentally challenged)
Some crank gears have a variety of markings on them. However, the keyway is directly in line with the #1 & 2 crank journal, and should thus always point exactly 45° to the driver's side at #1 TDC. I.e. exactly along the #1 cyl bore.
Don't forget also, that dot-to-dot is NOT #1 firing. It is the OTHER instance of #1 TDC, where the #1 exh valve is just closing and the #1 int is just opening. It is actually #6 firing. We build them at dot-to-dot (#6 firing) because it's easier to see them line up than at #1 firing. If you rotate the crank exactly 1 revolution from where it is in the 2nd pic, the crank dot will be at the top again, and the cam dot will also be at the top. #1 & #6 will both be at TDC again, except this time, it will be where #6 valves are "changing over", and also #1 firing.
The 1st pic has the cam sprocket one tooth off, in the retarded direction. (no I'm not talking about mentally challenged)
Some crank gears have a variety of markings on them. However, the keyway is directly in line with the #1 & 2 crank journal, and should thus always point exactly 45° to the driver's side at #1 TDC. I.e. exactly along the #1 cyl bore.
Don't forget also, that dot-to-dot is NOT #1 firing. It is the OTHER instance of #1 TDC, where the #1 exh valve is just closing and the #1 int is just opening. It is actually #6 firing. We build them at dot-to-dot (#6 firing) because it's easier to see them line up than at #1 firing. If you rotate the crank exactly 1 revolution from where it is in the 2nd pic, the crank dot will be at the top again, and the cam dot will also be at the top. #1 & #6 will both be at TDC again, except this time, it will be where #6 valves are "changing over", and also #1 firing.
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Joined: Feb 2015
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The only way to know it's ok is to put a degree wheel on and see where the ICL is. Compare to cam card to get your answer. There's been more than 1 that have struggled with bad engine performance on here due to installing a cam "dot to dot" only to find it's 8* off. Hope this makes sense.
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That actually looks like 1 tooth off to me.
The cam looks like it's at about 5:45, not quite exactly 6. So if you rotate the crank just a touch to get the cam to come around just a hair, you'll see it's actually one tooth off.
