Technical Timing on Stock 350 SBC

Hey everyone, I am trying to time my 350SBC and when I clamp onto No.1 cyl plug and then get my timing light hooked up and grounded, my timing marks on the balancer are WAY off from the pointer. As I look at the timing mark and compare it relative to the pointer bolted to the case I would say that it appears right around the 3 O'clock position while the pointer is at roughly 12 to 1 o'clock. If I loosen and rotate the dizzy to get the marks to move towards the pointer (so moving in a counterclockwise direction under the timing strobe) she starts to run like garbage and want to die once the mark gets right by the pointer. Any ideas as to what is going on here?

Best I can figure from the numbers, its a '71 350sbc and it would have originally been in anything from a C10 to a 3500.

 

depending on the water pump and balancer there are a few timing tab set ups for sbc that will screw you up.

if you can get a piston stop you can use the balancer and pointer of your choice and mark true TDC on the balancer
http://www.hotrodders.com/forum/true-tdc-using-piston-stop-78054.html
If you have a vacuum gauge you can get it close in the meantime, advance until the highest vacuum reading and then back it off 2 inches,

 

Unfortunately I don't have a vacuum gauge. I guess I'll have to try and find a piston stop.

I know I read somewhere about there being a 12 o'clock tab and a 2 o'clock tab...

 

the 12 o'clock tab is used with the long water pump so you can see behind it, with the short pump you cannot see as much there so they used the other one....

 

How do I tell the differemce between the long and the short pump?

 

This is what the waterpump and harmonic balancer arrangement relative to my timing tab looks like

 

And that is approximately where the timing mark hangs out wheni've got the strobe on it and thengun set to 8° BTDC

 

Quick way to tell a short or long pump is by putting your finger between the back of the water pump and the timing cover. A short pump almost touches the cover and a long pump has enough room to insert an average size finger.

 

it's a short pump, since the fan belt is up against the damper.

Since it's off that direction, maybe the damper outer ring slipped.

 

Just a thought, do you have an advance dial on your timing lite?
If so look and where its setting.

 

Looks life you have a mismatched balancer and timing cover. Just get a after market pointer and install on the two bolts on driver side time chain cover.

 

Silly question- are you checking for base timing with the vacuum advance still attached? If so, pull the vacuum hose off the distributor and plug it with a golf tee.

 

Ok if you don't know a long water pump from a short one you probably shouldn't be using a piston stop either. Not being mean or nasty but the old shop teacher me says that you are one of the beginners and not in the advanced class this year.

Do this:
Pull number 1 plug out.
After either pulling the coil wire out of a point style distributor or disconnecting the BAT wire from an HEI you will need to either bump the starter over with a remote button (best) or have a helper bump it over with the key while you hold your finger in/over #1 Plug hole and have the compression come up and blow against your finger. Do it right and it should be real close to top dead center. You should be able to look in the plug hole using a flashlight and see the top of the piston.
Now: put a socket and ratchet on the bolt on the crank and move the crank slightly back and forth until you can tell that the piston is at the top of it's stroke. You can probably use a heavy duty soda straw out of that 44 ouncer on the bench to hold against the top of the piston and watch it move up and down to figure out tdc.

Then put your mark on the damper to match the timing tab's "0" and you should be set to set the timing.