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Trying to put my HEI on my 54 3100. and I need to put #1 cylinder on top dead center.

I cleaned the ring on my fly wheel and found a mark then a circle then 2 marks and then a triangle...all within acouple of inches of eachother...? What mark is TDC and how do I know it's compression not exhaust?
Thanks

Put your finger in the #1 spark plug hole. When you feel the pressure it's coming up to TDC on the compression stroke.

I don't have any power to the motor yet.....Can you get the same thing with turning by hand? and how many plugs in ?
Thanks

Jimmi take plugs out to turn it by hand , when you are turning the engine over by hand with the fan belt watch the 2nd valve from the front close and keep turning engine till the stamped triangle on your ring gear lines up with the pointer in the timing hole in your bellhousing.That will take about another 1/3 turn. That will get you to tdc. There should be a raised ball on your flywheel or what I called a ring gear , that is your timing mark that you set with a timing light once the engine runs. I had to go through this a couple months ago. Murray

When i was trying to find TDC on mine, i had all the plugs in except #1, get somebody to crank the engine by hand and have your thumb or finger over #1 hole.
As to which mark is correct... im still trying to figure that out for myself.

Good luck

Here is the procedure from the 1954 Shop Manual. I've always followed a similar procedure, but I've used the embedded ball (aka bb), instead of the "U/C" mark, with good success. According to the manual, the triangle is to be used for checking valve timing.

The triangle is for checking cam timing, the ball is the timing mark most cases.
The ball is not TDC in most cases but 3-5 degrees advanced depending on the year.
261s have the ball at TDC at least in some years.
My 55 Shop Manual says to set the timing at the first radial mark past the ball.
This gets confusing I know but in the end timing by ear or with a vacuum gauge is best since parts get mismatched through the years.

How does a vacuum gauge help find proper timing?

Here's some explanation on using a vacuum gauge for timing and carb adjustment (etc).

The resultant settings are apparently not optimum but they are close.

Other explanations:
http://automotivemileposts.com/garage/v2n8.html
http://www.tuningmadeeasy.com/tuning/vacuum-gauge-the-wonder-tool/
http://books.google.com/books?id=Ai...=0CEgQ6AEwBg#v=onepage&q&f=false

Jimmi, on the relatively few engines I have assembled I have checked the factory TDC marks and found that they are not always accurate. That check is done by making a positive stop that contacts the #1 piston before it reaches TDC and rotating the engine gently by hand until the piston contacts the stop. A mark on the flywheel or harmonic damper is then made at that point.

Then the engine then is rotated in the opposite direction until the stop contacts the piston and another mark made. Actual TDC is midway between these marks.

Most I have checked have factory marks that are close but it's nice to know where actual TDC is. When degreeing in a camshaft it is essential to know the location of TDC to verify that the camshaft is in the correct pocition in relation to the crankshaft.

To some that may be an unnecesary step. However the camshafts I have bought from Crane Cams and Competition Cams for my daily drivers and street rod came with instructions that strongly recommend degreeing the camshaft in rather than relying on marks on the timing set and harmonic damper. So far the camshafts I have installed checked within a fraction of one degree of the desired position.

It's easiest to make the piston stop for a short block. With the heads installed I knock the porcelain out of a spark plug, thread the hole and install a bolt to create an adjustable stop.