351W Distributor install sanity check

[foothilltom 33]

Hi guys, wondering if this is the best I can do when installing the diz.  The crank is at 0 TDC and I can never seem to get the rotor to line up with spark plug #1.  Obviously, the rotor rotates backwards when dropping in the gear, but no matter how I seem to set up the thing, the rotor is either past #1 or ahead of #1 (like shown in the picture).   Is this "close enough" that can be fine-tuned with rotating the diz after the fact? 

My brain tells me #1 should fire around 10 degrees BEFORE TDC so I would think the rotor should be slightly PAST #1 when installed at 0 TDC.  Wondering if I'm explaining that well.

To simplify, what side of #1 on the distributor should I err on when I'm installing the diz since it never seems to want to drop exactly in.  Here is a diagram of what I have right now.

Thanks!

Tom

[Vicfreg 771]

I set my #1 cylinder at TDC with the cap on. I install the distributor, and mark the outside of the distributor housing where the #1 plug wire is.  

distributor rotates counterclockwise

I usually start to the "left" of #1 cylinder and try to get the distributor to rotate clockwise to land right on #1.   If you try it a few times, it should work.  

Also make sure your #1 is at TDC....I do that with my valve cover off and watch for no rocker arm/valve motion

 

[barnett468 418]

You likely need to rotate the oil pump drive shaft a little.

[Vicfreg 771]

Yeah, right...good point

[foothilltom 33]

Thanks guys.  I have a little gizmo to rotate the oil pump shaft.  I'll see if I can get it "nuts on" again tomorrow.

[barnett468 418]

You want your rotor (the red arrow) to be be exactly where it is in your drawing in relation to the cap, because the rotor rotates counter clockwise and the spark actually jumps a small gap from the leading corner on the rotor contact to the closest corner on the distributor. If the red arrow was lined up dead center with the 1 on the cap, it would have way too much advance.

After it is installed, you can connect number 1 plug wire only and check the timing with the ignition key on while you jump the large front post on the starter solenoid to the small post right next to it with a screwdriver or similar. If the engine is completely stock, 8 degrees of advance is a good place to start, if it has a performance cam 10 degrees is a good place to start.

 

 

 

[barnett468 418]

9 hours ago, foothilltom said:

Thanks guys.  I have a little gizmo to rotate the oil pump shaft.  I'll see if I can get it "nuts on" again tomorrow.

Try rotating it just 1/8th of a turn unless your rotor lines up just like your drawing, in which case, it is already corect.