Unleaded Avgas

[rvsxer]

Originally Posted by Carl Froehlich

I wish I could get 94UL! This fuel is simply 100LL without the lead, so all the costs of special blending, segregated transport and storage are eliminated.

Carl

Transport is not going to change. The quantity of fuel is so small it is not worth the losses of pipelining. This is right from our refinery rep at Flint Hills Refinery here in Minnesota, a leading producer of 100LL. Furthermore, just eliminating the lead content is not enough. If that was the case it would've happened years ago. Another anti-knock additive has to take its place.

[tspear]

Originally Posted by rv7charlie

Carl's post raises an interesting point. The fact that turbo'd and other high performance (typically business use) aircraft consume 60-80% of the avgas, means that they are timing out their engines a lot quicker, too. If they were given the option to use fuel that was even 5% cheaper, how long would it take for the vast majority to convert to lower octane engines at overhaul?

A long time. To get to a lower octane fuel you need one of three things.
1. EFII
2. Lower compression
3. Reduced performance

Try explaining and passing the first option to the FAA.
Or the second and third to the airplane owner.

Tim

[RV6_flyer]

Lycoming Service Letter 270 says that oil change interval can be doubled with unleaded fuel.

Switch to unleaded fuel and oil change is 100 hour instead of 50 with spin on filter or 50 hours instead of 25 hours with screen. We will still be required to change spin on filter every 50 and screen every 25. Many of us using unleaded fuel would end up changing oil every 4 months per Lycoming time interval instead of time in service.

I am one that wonders how many years it will take to get all the 100LL out of the tanks and only the unleaded replacement available.

[grubbat]

I've got a couple of wide band o2 sensors waiting to be installed when the unleaded thing comes along.