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Strange cam timing issue; Engine runs better with timing set wrong
Topic Started: Apr 16 2011, 06:28 PM (679 Views)
Tofuball
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Strange Mechanic

1994 xfi. Bone stock.

Ive checked very carefully, but in every orientation of the cam gear, I have bad vac flutter, poor low end, and get 40mpg max.

Today I set the gear a whole tooth advanced. Flutter was cut in half, low end was greatly increased, and by the mpguino I got 50mpg on the way home.

I am thinking of advancing it another tooth. Any idea why my cam gear is so wrong? Or how I can find out where it is supposed to be?
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Good bye


Make sure the dowel pin is down when checking cam marks. Your cam gear has two sets of marks. Use the mark that is up when the dowel is straight down.
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mwebb
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FOG

make sure the crankshaft pulley key has not sheared and allowed the crankshaft pulley to spin a bit in relation to the crankshaft , if this has happened , you would not be able to correctly set cam timing.

i never saw this on a Metro , but Woodie has
i have seen this on other engines , it is an engine killer as the crankshaft is destroyed by the event
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Tofuball
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Strange Mechanic

me and my metro
Apr 16 2011, 06:38 PM
Make sure the dowel pin is down when checking cam marks. Your cam gear has two sets of marks. Use the mark that is up when the dowel is straight down.
Tried it both ways and it seemed to behave exactly the same either way.

The key has not sheared, but that is a good thing to check for.
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