5 replies to this topic

[nobbycameron]

hello, im having a bit of trouble finding where i should set my ignition timing.

ive got a 1380 with sw5 cam, metro electronic ignition and stage 3 head, does anyone have any ideas where to set the timing,

ive got a timing light but dont where the best place to set it is,

any help would be appriciated

cheers

[dklawson]

Others will chime in about so many degrees this-or-that before TDC. I will not.

Is your timing light an advance type (knob on the back with numeric scale) or regular? If you have an advance type light, connect it to your #1 plug wire and start the engine. Bring the engine RPM up (using the idle screw on the carb linkage) until the engine is running at 4000 RPM. Leave the engine at this speed and set your timing light to "32" degrees. Point the light at the timing pulley and move the dizzy housing until the timing light shows the ZERO mark and POINTER lined up, then lock the dizzy down. Return the car to its normal idle speed and for reference, use the timing light to determine your idle advance. Record the idle advance value and the RPM.

Test drive the car. Put it under load by selecting a HIGHER gear to accelerate uphill (or similar). You're trying to make the car knock and ping. If you hear any pinging, hook your timing light up again and retard the timing about 2 degrees from where it was. You can do this at idle based on the numbers you recorded above. You do not need to do the 4000 RPM check again. Repeat the test drives and adjustments as necessary until you can put the car under heavy load and NOT hear any knocking or pinging.

Using this method you determine the MOST advance your engine can handle (for its specific condition, state of tune, and quality of gasoline) without pinging.

If you do NOT have an advance type timing light (no knob/dial on the back) then you have to take the additional step of making a 32 degree mark in paint on the timing pulley. I can add details on this in a future post if necessary.

[nobbycameron]

Thats great advice, thanks, my timing light has a dial at the back so i will be able to set it to 32 degrees. I will have a play on sunday and let you know how i got on, thanks again

[lrostoke]

I read of a way the other day using a vacuum gauge..

Connect the vaccum gauge to the inlet manifold, I used the brake servo take off.
Then its dead simple, advance the dizzy till the vacuum gauges gives the highest reading, then retard the dizzy so the reading drops by approx 1/2" of vacuum.

http://www.classic-c...acuumgauge.html

Tried this method on 2 Mini's so far seems to work a treat.

[Grimmy@JHE]

what about a standard 1275 on electronic ignition with a hiff 44? carb is running rich though but i was told to set the ignition timing first and i dont think it will rev to 4000 and stay there. what do i do? i have an ignition timing light with the knob on the back.
many thanks

[dklawson]

Vacuum tuning can be done for both the mixture and the ignition timing. However, like the method I described above, you must do a driving test and make corrections to the timing after setting the ignition this way. It's imperative that you retard the timing if any knocking or pinging is heard under load.

Grimmy, if your engine's condition is such that you don't think it will even rev to 4k RPM, I'd start with a basic static timing setting between 5-8 degrees BTDC. That should allow you to make your carb adjustments. After that you should be able to rev higher and perform the high speed (max advance) timing setting.