5 replies to this topic

[minivanman8]

1275 a+ block, a series head with stage one.

What timing figures should I be looking for?

[cal844]

8-10 i believe, my dad sets it by ear( it runs better than setting with the light)

[minivanman8]

I assume at 1500 revs without vac connected?

[dklawson]

There is not a one-size-fits-all answer to timing.  Each engine will behave differently depending on its condition, state of build, and the fuel you use.

 

I suggest that if you do not already have one, buy an "advance timing light", the type with a knob or digital display that is used to "move" the time the strobe fires.  Bring the engine to operating temperature and set the timing light for 32 BTDC.  Increase the engine sped to 4000 RPM using the idle adjustment screws then shine the light on the timing marks and turn the distributor body until the ZERO marks line up.  Lock the distributor down and return the idle speed to where you want it to be.  

 

Test drive the car by placing it under a heavy load.  Accelerate up hill in too high a gear.  During this test drive you are trying to make the engine knock and ping.  If you hear any such noises, stop and retard the timing 2 degrees from where it is (this can be done at idle, you don't have to take it back to 4k RPM).  Then repeat your load test.  When you reach a point where the engine no longer makes bad noises you have reached the maximum advance your engine can handle for its combination of components and the fuel you are using.  If you change the engine parts or the grade of fuel you buy you will need to do this timing and load test again.

[minivanman8]

Thanks for the info, I'll give it a try.

I guess I'll have to set to to 32 at 4k first and adjust later as I have no MOT at the minute!

[minimender]

As dklawson says, advance till it pinks under load then knock it back a bit, you will probably go to 34  depending on compression.  Not best to set it by numbers as wear in timing chain and dizzy parts make all engines slightly different regarding timing.