I recently traded a tired out jeep for a decent 79 Z28 with a previous engine rebuild. I believe that the car has a performance cam. I'm thinking that the timing chain may be off a tooth, I'll have to check. The Haynes manual says to line the dots up (this is normal) The Chilton manual says to line the dots up, but to make sure that the cam shaft gear's dot is pointing torward the top of the engine. I'm real confused with the different information. I normally line the two dots close together and life is good. Am I not thinking this out or are both ways correct????? Any help is appreciated.

They're both correct. You line up the dots together (cam gear dot down, crank gear dot up) to make sure the cam timing is correct. However, this is not TDC#1; it's TDC#6. If you turn the engine over one full revolution both dots will be straight up which is TDC#1.

Jody

It seems many cams are to be installed , say, 4 degrees advanced. Are they ground so that you still line up the dots? I don't need a detailed explanation - I'll research is I need to but this winter I'll be pulling the heads off and it's a good time to look at the cam, too.

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Rick Dorion
69 RS Conv,355,M20,4:10

You need a degree wheel for anything other than straight up...

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...Dennis
'69 RS Convertible w/SS trim (http://www.camaroslimited.com/memberscars/den.htm)
'96 Z28SS #1679 of 2410 (http://www.camaroslimited.com/graphics/memcars/96ss.jpg)
"The Club" (http://camaroslimited.com)

Comp Cams grinds their cams (at least every one I've purchased) with 4 degrees advance in them. If you install it straight up with the dots, you're really advanced 4 degrees. They do it that way on purpose, that's where they say their grinds perform best. Unsure about other manufacturers. Of course if you use a degree wheel, you will always know for sure.