Timing problems

[paulsv8manta]

Hi guys, finally got the engine running for the 20 min cam run in.

Now trying to set the timing with a strobe light, when i set the timing to 2 degrees btdc the engine runs really rough with the occasional popping.

When I turn the distributor back further to what looks like 30 degrees btdc the engine runs a lot smoother with no popping!

What am I missing?

[Darkspeed]

Hi guys, finally got the engine running for the 20 min cam run in.

Now trying to set the timing with a strobe light, when i set the timing to 2 degrees btdc the engine runs really rough with the occasional popping.

When I turn the distributor back further to what looks like 30 degrees btdc the engine runs a lot smoother with no popping!

What am I missing?

Fuel - By way of it sounds like not enough - the weaker the mixture the more timing you will need - Also Popping !! - I take it you mean spitting back.

A weak mixture takes longer to burn than a rich one as the flame travels slower due to the lower charge density. Richen up the mixture and you need less timing.

2 degrees is however ridiculous - Unless for cranking (50rpm) on an ECU.
For idle timing 10-12 but this depends on the type of equipment.

My advice - 12 degrees and richer.

I ran 14 on mine but I had a non Vac dizzy stopped to 8 degrees dizzy advance.

[DaveEFI]

Hi guys, finally got the engine running for the 20 min cam run in.

Now trying to set the timing with a strobe light, when i set the timing to 2 degrees btdc the engine runs really rough with the occasional popping.

When I turn the distributor back further to what looks like 30 degrees btdc the engine runs a lot smoother with no popping!

What am I missing?

It may be a silly question - but are you driving the timing light off the correct cylinder?

No1 is the front nearside one. If that's correct, I'd check the TDC mark is actually at TDC.