Ignition Timing

[JD1964]

I know there are factory settings but with mods and all that, sometimes adjusting ignition timing to other than factory settings can help performance.

I currently have mine set at 12 BTDC and it runs good with no spark knock on 87 octane. I was told by a particular tuner I can go up to 14 BTDC as long as I run high test gas.

What are your thoughts on performance differences at different timing settings? Will ignition timing that is advanced hurt top end? I don't expect a ton of bottom end tq from a 5.0 so I'm wondering if there is a trade off. My point is, why would you want to make an adjustment that would compromise top end on a smaller motor such as 5.0 that depends primarily on top end to get the job done?

I guess to be more specific. Will difference timing settings affect either top or bottom end power/tq?

 

[mikestang63]

The factory sets the timing conservative because the cars are made for the masses and for emissions. However, on a stock or nearish stock engine, the difference between 12 and 14 BTDC may be negligable and not worth the increased price of premium gas. I wouldnt run 14 or more degrees on anything less than 91 and keep an ear out for pinging or excess temperature. The inreased timing will help lower end performance and most of us don't spend most of the time at top end in our daily driving.

 

[Grabbin' Asphalt]

I guess to be more specific. Will difference timing settings affect either top or bottom end power/tq?

Another thought also, ...when you max out a performance timing set up, you are very sensitive to climate change etc.. Unless you like to change the timing a lot on a DD, get it kinda close but leave a little room so you're not under the hood all the time doing the same thing.

 

[reldla1996]

Taking data out of a book entitled 5.0L Ford Dyno Test, written by Richard Holdner, he performed a dyno test on a stock 5.0 except for flowmaster mufflers, and changing the timing from stock 10 degrees to 15 degrees increased power by 1 hp at 2500, 3 hp at 3500, 7 hp at 4500, and 6 hp at 5500. I've always ran mine advanced, ran premium gas, and enjoyed the difference. Can't say I ever had to change timing with weather differences, but all engines are different.

 

[JD1964]

I think I'll try 14 with high test.

 

[mikestang63]

Taking data out of a book entitled 5.0L Ford Dyno Test, written by Richard Holdner, he performed a dyno test on a stock 5.0 except for flowmaster mufflers, and changing the timing from stock 10 degrees to 15 degrees increased power by 1 hp at 2500, 3 hp at 3500, 7 hp at 4500, and 6 hp at 5500. I've always ran mine advanced, ran premium gas, and enjoyed the difference. Can't say I ever had to change timing with weather differences, but all engines are different.

Exactly my point. For the majority of time, you are driving under 4000 rpm in normal daily driving. It's up to each person to decide if 3 hp worth the extra 30- 50 cents a gallon. If you drive 15000 miles a year and average 18 mpg , that's a lot to pay for 3hp- almost $400.

Now, to provide full disclosure, I run 14 degrees and run 93, but I put less than 8k miles on my car a year so the cost is not as much as a DD. If it were still a DD, I'd back it down to 10-12 and run 87 and save the money for other go fast parts.