TDC proper stroke and timing chain installation....

[fairlaniac]

First off I want to thank Blair Patrick for telling me I'm fine. I trust him but I want to understand what is going on and don't want to keep bothering him. So I appreciate all of your help Blair.

So my issue is I bought the Cloyes billet timing set with 9 position indexing. I also have a new cam from Bullet. in the few FE's I've ever assembled I always followed the Ford service manual. To position the sprockets I put the crank sprocket with the dot up. Then install the cam with the dot down opposing the crank dot. However the cam pin has always been on top or 180 degrees from the sprocket dot. My Cloyes cam sprocket has both the dot and the pin hole on the same side. So if the cam dot is down, so is the cam pin. So per Blair's "I'm ok" and what I think is right I am still thinking do I have it right? I'm having thoughts firing the engine up in a week or two and the thing just cranks and doesn't start.

With the #1 piston at TDC and both dots opposing each other when I start to rotate the crank the intake valve should be the first to begin to open, correct? That is how I have it.

What I have trouble getting straight in my brain is I have a comp timing set on hand as well. Should I have chosen to use it. It has the cam pin on top like I am use to. If I would have used it, I would have needed to rotate my cam 180 degrees to hit the pin. So in my mind if I use the Cloyes cam gear and for example the first lobe is pointed at 12 o'clock. If I chose to use the Comp gear I would need to rotate the cam 180 and that referenced lobe would now point at 6 o'clock. Had the Cloyes cam gear had the pin at top I probably would have moved on and never thought twice about it. This just has thrown be for a curve.

So as long as my #1 piston is at TDC and the #1 intake valve begins to open I am ok?

So if my #1 piston is a t TDC as above the ignition doesn't fire until the next 180 degrees when both valves are closed and the piston is coming up for compression, correct?

It's only 16 years since I assembled my last FE, it seems longer :-)

Thanks!

[CaptCobrajet]

Doug, if you line it up "dot to dot", and then make one turn of the crankshaft back to TDC.......take a look at your cam pin.  It will be at 12 o'clock on the cam.  If it makes you feel better, make yourself a punch mark on the gear that lines up with the dot that is "up" on the crank.  The crank does not care if you have the pin up or down, as long as you check your events. The indicator and the degree wheel will tell all.

[fairlaniac]

So if my damper is at TDC, the #1 piston is at TDC, the distributor is pointing at #1 cylinder, when I begin to rotate the engine the intake valve begins to open. Wouldn't the distributor have just fired the cylinder just behind the opening of the intake valve? Does the ignition not fire the cylinder after the intake valve just closed (charged)and the piston is TDC (compression).

I'm sure I'm over thinking this and just got my thoughts scrambled but I won't be happy with myself until I "get it".

thanks for your reply.

[CaptCobrajet]

The compression stroke is still the compression stroke.  Leave the distributor on the bench for a minute.  Once the cam is degreed, and the engine is all together, roll it around and set your valve lash.  Then, roll it around to TDC.  If you have both valves slightly open, you are on overlap.  Rotate again to TDC.  Both valves should have lash.  Now you are on compression.......drop the distributor in and line up #1.

The part you are struggling with has nothing to do with ignition timing.  The cam gear either positions the cam on overlap, or on compression stroke.  They are 180° apart, so rotating the crank one turn moves the cam 1/2 a turn......180°, so it does not matter where the pin is.....at 6 or 12 o'clock.  Rotate it one crank revolution and it will be opposite.  When you degree your cam, rotate the engine until the lobe is on the base circle before you start trying to read any numbers.  It will all take care of itself.

[1964Fastback]

Doug,

You say you have two different timing sets and the cam gears are different, right?  One has the pin and the dot on the same side, and the other has them opposite each other?  Have you looked at the bottom (crank) gears?  Specifically, the relationship of the dot on the crank gears to their respective keyways?  I'm wondering if different timing set manufactures do it differently.  What I'm getting at is you could use either timing set and be okay as long as the dots lined up.  But you couldn't (for whatever reason) use the top gear from one set and the bottom gear from the other.  Not sure if this is the case or not.

Pat

[blykins]

Same deal with camshafts with dual dowel pins.  You sit there wondering, so which way do I put it???  Like Blair said, it doesn't matter.  At this point in time, the engine doesn't know if it's on a compression stroke or exhaust stroke.  When you degree the cam, run the valves, stab the distributor, etc., it will all clear itself up. 

[fairlaniac]

It's starting to click now. I think I'll take a break and wait for the push rods to show and then go from there. Sometimes you get stuck on a thought and.........

Thank you all!

[BattlestarGalactic]

You can watch the lifters move.  Once the intake lobe goes down the #1 piston will be coming up.  That will be TDC compression.