jwaked

I live in Panama city, Panama and is really hard to find race gas. Has anyone tried air plane gas on their NA LS1? Any comments? Is it good or bad and how would you mixed it? What octane does it have?

Thanks

Jay

Rich in NC

Well, here's the problem with AV gas.. It's leaded.. even the low-lead and many of the UNleaded gas still has some lead in it, because of the valve seats in airplane piston motors, plus IIRC it has a octane boosting effect. I would not recommend it for a car with cats or o2 sensors, unless you like replacing them! <img src="images/icons/rolleyes.gif" border="0">

jwaked

But my cats will be replaced by an off road pipe soon.

Jay

RPM WS6

iTrader: (3)

Try talking to some GN/Turbo Regal guys (www.turbobuick.com). I know they regularly use AVGAS when running high (like 20psi) boost levels.

Big Mike

iTrader: (4)

[quote]Originally posted by jwaked:
<strong>But my cats will be replaced by an off road pipe soon.

Jay</strong><hr></blockquote>

You still have 2 O2's on the headers. If you run leaded gas, you'll roast them.

Nightclaw

Something else to consider is the possibility of building lead deposits on the valves and cylinder walls. Frequent and/or prolonged use of leaded fuels will leave these deposits, causing "hot spots" in an engine, thus possibly causing pre-ignition. I don't know how much of a problem this would be with 100LL (blue dye), but regular 100 avgas (green dye) will definitely cause lead deposit problems over time.

Oh, and for the record, avgas comes in the following flavors:

80 octane unleaded (red dye - practically extinct)
100LL octane (blue dye - LL="Low Lead")
100 octane (green dye - regular lead)

I think 110 is available at some airports, but I've never seen it so I don't know what color dye they use.

[ December 11, 2001: Message edited by: Nightclaw ]</p>

Trevor @ Texas Speed & Perf.

iTrader: (3)

I wouldn't recommend running avgas in a car at all. An airplane engine NEVER sees the RPM's that we do (6,000+), and the fuel has a much slower burn rate than unleaded pump gas. I've seen cars run slower with more octane because you do run into a slower-burning fuel without an engine that can really utilize the added octane (i.e. higher compression, etc.). I don't think avgas was formulated to turn the kind of RPM's we do, and you have to remember that an airplane is burning this fuel at high altitudes. Just some stuff to think about. Take it for what it's worth. <img src="graemlins/gr_xmas.gif" border="0" alt="[santa]" />

Visceral

iTrader: (1)

I used to run 116 leaded in my Syclone at the strip. I had a second 02 sensor that would last about 1 year of a track session about every two weeks. (in other words, not all that long).
I would put regular O2 sensor in it when I went back to the tank of Unleaded.

THis was really easy on the Sy because the aftermarket downpipe 02 bung was in plain vew under the hood. I could change it at the gas station with the wrench I kept in the truck in about 2 minutes.

If you arent willing to go through the process of changing out the O2s really often, I wouldnt do it. o2 sensors are still spretty spendy these days.

chris

Visceral

iTrader: (1)

Typical AVGas is 100 octane leaded BTW.

haole_boySS

iTrader: (1)

I have to drop my .02 in on this one. I lived in Hawaii for 6 yrs. My neighbor and his brother both had Vega's that they raced. Both of them were running 400 sm blocks that were destroked to 377 cubes. They were running 12.5:1 compression and burning Aviation fuel. The octane on the fuel they ran was 112. I didn't know if this was average or not but I had never heard of running AV fuel before anyway.

But like everyone has said, leaded fuel will roast the O2 sensors.

Andy

ChrisB

The leaded part isn't the biggest deal - like visceral pointed out you can get a suprising amount of life out of sensors - but you will replace them and it will be an extra cost eventually.


Trevor hit the nail on the head - Av gas isn't forumlated for use under the same conditions a car sees - airplanes operate at much lower rpm's, at more of a continuous load, and the air is *much* thinner. Also the 100 octane rating more than likely isn't the r+m/2 you are used to, so you may not even be getting that.

Not that it was your question, but you probably don't need to be running high octane gas anyway - not on any kind of NA ls1 unless your compression is up there.


Chris

roy

I doubt this engine operates much lower , in fact i bet its stesdy stste rpm is way higher than most folks are willing to turn for an extended time.

Bill

Aviation fuel has additives to prevent freezing at high altitudes which lead to nasty deposits in the motor. I know this only from the advice of a top fuel pro drag racer who called it "Black Death" because of the deposits left on the heads. Most GN cars do not run this, a few do.