can't time my fresh motor

DarkoStoj

Founding Member

Sep 4, 2002

929

13

39

Detroit

Aug 8, 2006

#1

• Aug 8, 2006

• #1

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

New Member

Jul 13, 2006

109

0

0

Joliet, Il

Aug 9, 2006

#2

• Aug 9, 2006

• #2

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

 

Max Power

Active Member

Jul 31, 2003

1,774

1

36

St Paul

Aug 9, 2006

#3

• Aug 9, 2006

• #3

Dizzy off?

Vacuum leak?

 

xoxbxfx

Founding Member

May 9, 2001

3,959

0

0

Southlake, TX

Aug 9, 2006

#4

• Aug 9, 2006

• #4

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

Founding Member

Sep 4, 2002

929

13

39

Detroit

Aug 9, 2006

#5

• Aug 9, 2006

• #5

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.

 

G

gsxrken

Member

Sep 12, 2005

206

1

18

Weschester County, NY

Aug 9, 2006

#6

• Aug 9, 2006

• #6

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

Active Member

Jul 15, 2003

892

1

29

Massachussetts

Aug 9, 2006

#7

• Aug 9, 2006

• #7

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

Founding Member

Jul 25, 2000

2,437

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47

SoCal

Aug 9, 2006

#8

• Aug 9, 2006

• #8

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

Active Member

Dec 15, 2003

1,360

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37

Cecil County, MD

Aug 9, 2006

#9

• Aug 9, 2006

• #9

DarkoStoj said:

mild to medium cam

Click to expand...

Check firing order on cam card.