can't time my fresh motor

[DarkoStoj]

I don't know what the problem is, but I can't get the motor to run unless I am above 30* BTDC at idle.

Here is a rundown on the motor

68 302 block punched to 306
mild to medium cam
world windsor sr. heads w/ 1.7 rockers
victor jr intake
mallory unilite dist
speed demon 750 double pumper carb.

The motor will just simply not run when I try to bring it under 30* BTDC, and it is running incredibly rich right now also.

 

[GoinBroke]

It sounds like the balencer is not matching true TDC, pull the #1 plug and verify if it is correct.

 

[Max Power]

Dizzy off?

Vacuum leak?

 

[xoxbxfx]

are you sure you are not off a gear on the dist?? Or two? I would check TDC again and verify the pointer is pointing to 0*

 

[DarkoStoj]

i checked to make sure tdc was correct on the balancer when I was putting the motor together.

no vacuum leaks, dizzy isn't a tooth off.

 

[gsxrken]

This may sound too easy, but maybe you need to crank in more idle screw. Did the carb come with a spec about how much transition slot should be showing?
Once you can idle with about 12* advance, run around adjusting your mixture screws with a vacuum gauge to obtain the most vacuum.

 

[jcode68]

Are you using a multiple spark box like MSD or Crane? I have read that these boxes can provide somewhat false timing readings due to the number of sparks performed at lower RPM's. I know my Crane Hi6 causes the timing light to "dance around" by a couple of degrees. Crane has the ability to disable the multi spark with the turn of a knob, allowing users to set the timing. Not sure this applies to your setup, but seems like you have a strange problem and maybe it's relevant.

 

[SoCalCruising]

I like the idle speed input. If it's too high, you will be adding mechanical advance to your base timing and getting a higher-than-actual reading.

If you have an MSD/Jacobs/etc. multispark box, plug off the vac advance, and then time the engine at 3500RPM to whatever you are targeting (32-36*, typically). The base timing SHOULD then be okay, if your dizzy is working correctly (i.e., mech. advance is working properly).

Otherwise, this is strange.

 

[dodgestang]

mild to medium cam

Check firing order on cam card.