Cam Timing Question - tensioning timing belt
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From: Helsinki, Finland
9201 was made to measure 944 cam and balance shaft belts. It was taken into use for 928 cam and alternator belts too as dealers needed it for 944 anyway. 32V 928 needed new tighter specs but that was several years after 9201 was introduced.
Its true that according to comparison test Kempf needs to be on tight side for 32V.
Its true that according to comparison test Kempf needs to be on tight side for 32V.
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Three Wheelin'
Joined: Dec 2001
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From: Florida
Here are the pics with crank at precisely TDC.
Pic 1 - TDC reading
Pic 2 - driver's side cam
Pic 3 - passenger's side cam
It is hard to see from the pic, but the passenger's side cam notch is just over the left edge of the raised part of the sprocket, to the left of which is the 'valley' of the sprocket that has the notch.
Pic 1 - TDC reading
Pic 2 - driver's side cam
Pic 3 - passenger's side cam
It is hard to see from the pic, but the passenger's side cam notch is just over the left edge of the raised part of the sprocket, to the left of which is the 'valley' of the sprocket that has the notch.
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Three Wheelin'
Joined: Dec 2001
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From: Florida
Zoom of passenger side cam notch and drivers side cam notch. You can see that the passenger's side notch is off by less than 1/2 of belt tooth. I guess that there is nothing that I can do to address that, is there?
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The cam gears are slotted, with a ±1 tooth range, so the small notch may never line up exactly. That's why the front notch is so wide.
The factory settings retard the 1-4 side by 2°, in an attempt to compensate for engine expansion when hot, which advances the timing.
The factory settings retard the 1-4 side by 2°, in an attempt to compensate for engine expansion when hot, which advances the timing.
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From: Glen Mills, PA
Cameron,
"Slightly to the tighter side of the middle" is still WAY too loose for a 32 valve engine, especially a GT. Before you button it up, go all the way to the top of the notch.
"Slightly to the tighter side of the middle" is still WAY too loose for a 32 valve engine, especially a GT. Before you button it up, go all the way to the top of the notch.
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Thread Starter
Three Wheelin'
Joined: Dec 2001
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From: Florida
I went all the way to the tight side of the range on the Kemph tool as per Earl's advice. Unfortunately, I did not see the advice of flushing the tensioner. I thought about the tensioner myself but ignored my curiosity since my wife was on me about our BBQ commitment this afternoon.
Thanks for all the advice, guys. I will let you know if I still get any warnings.
Thanks for all the advice, guys. I will let you know if I still get any warnings.
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From: saratoga, ca
my timing is exactly like this. remember, i set the cams to 2mm a side as well. (as opposed to the 1.7mm passenger vs 2mm driver side spec) If you think about it, the line up has nothing to do with cam timing, its the relativity of the two cams, and all the stuff it wraps around. at TDC, thats where the belt grabs both cams with their pulleys. changing timing wont do anything here as the cams move inside the hubs of the cam pulleys.
actually, it looks like about a 1/4 tooth pitch issue. again, it doesnt matter as long as the cams are timed correctly, and the alternative is to be much further off in the other direction.
mk
actually, it looks like about a 1/4 tooth pitch issue. again, it doesnt matter as long as the cams are timed correctly, and the alternative is to be much further off in the other direction.
mk