OK, I know our low compression engines don't require anything higher than 87* and I've always been a firm believer that higher octane in a low CR engine is just a waste of money, however, I know quite a few here (me included) have noticed some SOTP performance gains in their rigs by advancing the timing a few degrees
I'd like to get a little discussion going on our own personal experiences
When I first got my 80, she was originally set ~5*
After replacing a leaky O-ring, I figured I'd try the stock 3* setting, but she turned out to be a total dog and got even worse gas mileage (didn't think that was even possible lol)
A few days later, I bumped her back up to ~6* and she felt a bit peppier than before (much better than the OEM setting)
I later bumped her up to ~8* and she felt only slightly better power wise, but then I heard some light pinging under part throttle.
Rather than dial it back, I instead filled her up with mid grade (89*) and the pinging vanished.
Went through a few tanks this way and noticed I was getting around 20-30 more miles between fill ups.
Not much of a gain in mpg, but with the added power, I felt it was well worth the extra few bucks at the pump
Drove her like this for a while and would switch back and forth between 87 and 89 octane depending on weather and vehicle load.
Not surprisingly, the few times I was able to fill her with non-Ethanol 87*, she performed even better without a hint of pinging regardless of load and got almost 50 miles more per tank
Since non-ethanol fuel is getting harder and harder to find and fuel prices just keep going up, I dialed her back to ~7* a few weeks ago and that seems to be the limit for running Ethanol 87*
Anyways, after playing around with the timing on my '69 Road Runner for the past few days (apples to oranges, I know), I found she made the most power and got the best gas mileage running as much timing as possible on pump gas, but still under the factory total timing setting, so she still has a bit left for when I fill her with race gas.
So now this has me thinking about pushing the limits of timing on my Cruiser and possibly stepping up to 91* or even 93* just to experiment
For those that have messed around with your timing settings, post up your experiences.
How much advance?
Fuel type used?
Performance gain?
MPG?
Lighter wallet?
I'd like to get a little discussion going on our own personal experiences
When I first got my 80, she was originally set ~5*
After replacing a leaky O-ring, I figured I'd try the stock 3* setting, but she turned out to be a total dog and got even worse gas mileage (didn't think that was even possible lol)
A few days later, I bumped her back up to ~6* and she felt a bit peppier than before (much better than the OEM setting)
I later bumped her up to ~8* and she felt only slightly better power wise, but then I heard some light pinging under part throttle.
Rather than dial it back, I instead filled her up with mid grade (89*) and the pinging vanished.
Went through a few tanks this way and noticed I was getting around 20-30 more miles between fill ups.
Not much of a gain in mpg, but with the added power, I felt it was well worth the extra few bucks at the pump
Drove her like this for a while and would switch back and forth between 87 and 89 octane depending on weather and vehicle load.
Not surprisingly, the few times I was able to fill her with non-Ethanol 87*, she performed even better without a hint of pinging regardless of load and got almost 50 miles more per tank
Since non-ethanol fuel is getting harder and harder to find and fuel prices just keep going up, I dialed her back to ~7* a few weeks ago and that seems to be the limit for running Ethanol 87*
Anyways, after playing around with the timing on my '69 Road Runner for the past few days (apples to oranges, I know), I found she made the most power and got the best gas mileage running as much timing as possible on pump gas, but still under the factory total timing setting, so she still has a bit left for when I fill her with race gas.
So now this has me thinking about pushing the limits of timing on my Cruiser and possibly stepping up to 91* or even 93* just to experiment
For those that have messed around with your timing settings, post up your experiences.
How much advance?
Fuel type used?
Performance gain?
MPG?
Lighter wallet?