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Discussion Starter #1
I know that top dead center refers to piston number 1- ie the first cylinder on the PASSENGERs side. I have to remove my DRIVERS side cylinder head due to a head gasket leak. Is there any way that I could determine top dead center from one of the Driver's side pistons. Or example one of the cylinders in 90 degrees off number one then I could bring that piston to TDC and mark it out on the balancer and calulate No. 1 from there. Any suggestions on this. I hope my question makes sense, it seems easier that the other ways of finding TDC. Thanks.
 

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Simple, just line up TDC on the damper! I don't understand why you need to find TDC to change a head gasket, also I wouldn't change one side and not the other. If one failed, chance are what ever forces that caused it to fail have also worked on the passenger side too. You'll have the intake and coolant removed anyway, not too much work now to do the second one....but a lot more work to do it later on!

Besides, we wouldn't want to see you end up with a dofus award on here for that.
 

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Sure...

Remembering engine rotation is CW, if you're running a traditional 289 cam, #5 (front DS) is right after #1 in the firing order. You'll need a dial indicator and degree wheel. Rotate engine until #5 is at TDC compression (both lifters down). Install pointer (bent piece of wire will do, bolted to the engine somehow) and adjust degree wheel to read 90 degrees. Then, rotate engine back (CCW) beyond 0 degrees slightly, then rotate back (CW) to zero.(Most degree wheels have multiple scales of degrees so this shouldn't be a problem...in any event, the dwell between the two TDC's is 90 degrees) Note where 0 timing mark on damper is in relation to stock timing pointer on front cover; re-mark if necessary or install timing tape.

A variation of this method can be used with a positive stop in the spark plug hole on #1 as well, taking the average degree reading between the stops to extrapolate the TDC point. That would save the cost of a dial indicator if you don't have one. You can also build a positive stop for #5 out of a piece of flat steel and 3 bolts, two of which bolt the flat to the block using the head bolt holes and one which acts as the stop for the piston...

Have fun!

Edited to add that, while composing this detailed response, other, more obvious ones appeared. It never occured to me that you would want to trust the stock timing marks and that you were wishing to determine absolute TDC. I prefer doing it on the front crank throw as crank twist can cause reading anomalies as one moves farther back on the crank...well, anyway, at least the method is in the archives *G*. And BTW, there's no need to disturb anything that's not damaged. We pull and replace gaskets on single banks all the time, whether on industrial V compressors or racing engines...
 
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Discussion Starter #6
Further Information- I already changed the drivers side head gasket, but while I was in it, I forgot to check and mark TDC (OK Stupid). But now I don't want to take that side off again, it was a real pain with the exhust and all. I can't just look at the damper because the marks are gone or incorrect.
 
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Discussion Starter #7
That is exactly what I was looking for. Six is at the top of its exhaust stroke when 1 is at the top of compression, or something like that. Anyone care to confirm?
 

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Just think about it - Firing order is 1 5 4 2 6 3 7 8 (early) or 1 3 7 2 6 5 4 8 (late). Since we're dealing with 720* of revolution, #6 will be 360* from #1, or 1 revolution..../forums/images/icons/wink.gif
 
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