www.ColoradoClassicBroncos.com

I was out in the garage tonight fiddling around with things and decided to pull a spark plug on the Bronco. Here are three plugs from different sets I've installed:

- Plug on the right was the original that the PO installed and was run only on the carb. The carb was tuned as well as could be with the old cam.
- Plug in the center was run with the carb and later switched to early EFI and different cam. The insulator was slightly cleaner. Honestly though, I was disappointed and started to doubt whether Megasquirt could accomplish my goals.
- Plug on the left was just pulled tonight. It has been installed for several thousand miles. The insulator is still like-new clean. I'm not sure they will stay that way, but the ground electrode has a nice light tan coloring indicating good burn characteristics.




This was really encouraging since I have been banging my head against the side of the truck most days trying to get this system perfect. I don't have hard numbers yet, but mileage was a solid 10-11 mpg average with a carb and aggressive cam and now is an indicated 15-17 mpg average with EFI and a mild cam. Even if the real average ends up being 14-15mpg, that is still a 40% improvement along with other EFI benefits.

Wow, that is an amazing improvement.

Agreed, wow. How much of that was the ability to finely tune it?

Sent from my SM-N920V using Tapatalk

Justin wrote:Agreed, wow. How much of that was the ability to finely tune it?

Sent from my SM-N920V using Tapatalk

It was most of it. The carb didn't have the ability to tune for every condition, so the tune was a compromise to make it run well and that compromise usually error-ed to the rich side of things.

Megasquirt has been a pain to tune because there is so much control and I have no starting point and poor documentation. But persistence seems to be paying off.

I have hope now of meeting my goal of getting a catalytic converter on there some day and not ruin it with a poor tune. My wife was already excited that the garage doesn't smell like gas every time I come home from a drive.