Base timing bump 5.0 Ford...

In reply to ebonyandivory:

Its been happening over multiple tanks. I just checked timing and it is 12deg. It happens at light throttle, 5th gear going up a slight incline mainly.

CGLockRacer wrote: Its been happening over multiple tanks. I just checked timing and it is 12deg. It happens at light throttle, 5th gear going up a slight incline mainly.

Check the spark plugs. I have a 3.8 which is a lot different but it started pinging just like yours. Flooring it stopped the pinging. Changing octane, gas brands and additives did nothing. I found #6 spark plug had some ash on it. I finally found out that the valve cover had a defect that let oil into the PCV system causing that one plug to ping. A oil separator in the PCV line fixed the problem.

Yes, my guess is that there is something in the combustion chamber lighting off the incoming air/ fuel prematurely.

I guess the cheapest possible fix is new plugs.

Edit: Or even cheaper is retarding timing to factory setting and try that.

I run base timing of 16 btdc in the summer; 18 in the winter. We altered the wide open throttle advance curve via tune/chip to limit total advance to 34 degrees. Aluminum heads (on mine) and premium fuel help manage detonation which is pretty much non-existent. Stock short block (100k mile), AFR165 heads, bigger throttle body, maf, 24lb injectors, ported lower Explorer intake, 1 5/8" shorties with dual 2.5" system, custom cam with similar valve events to CompCam XE258, 1.7 roller rockers -- and it consistently gets 16-18 mpg around town and 25-27 mpg on the highway. The advance move from 10 to 16-18 degrees makes a huge difference on mine in bottom end torque, drivability and fuel mileage. FWIW

In reply to MichaelYount:

Thank you! I guess I'll have to buy a new timing light and do it myself!

I run a 5.0 that is mostly stock from a 89 fox. only difference is I have a e303 cam (slightly hotter than stock), and a lightweight flywheel.

I usually run about 16 base. I have run more without issues with pinging, but then my cold idle surge is worse and it develops a warm idle surge. (idle surge may be a different issue altogether, but point is that base timing can affect other things you may not intend as well).

Really good reading for understanding the computer programming of the era:

www.veryuseful.com/mustang/tech/engine/EECIVInnerWorkings

Good thing I checked, I guess. Mine was set to 20 degrees btdc. oooops.

You pulled the spout out (disabling computer control of timing) before checking it with the timing light, right?

In reply to MichaelYount:

This seems to happen a lot in my experience. SPOUT has to be pulled. HAS TO!

Yup. I think what happened is that while installing the engine I marked every 10 degrees on the crank pulley with a white marker, and I marked 10btdc with a red marker. You know, since that's the important one right? Then when I actually went to time it up, I forgot what the marks meant, and assumed the red mark was TDC, so I went one mark over from that.

funny thing is I never heard any pinging at 20 btdc, even on E36 M3ty gas and pulling 7000lbs.

I moved it back down to around 14 btdc. It's different now. Not really better or worse though. A little more idle surge, oddly enough.