high octane fuels

[mousecatcher]

I received this email this morning from "Sunoco Race Fuel Tech" (srftech@sunocoinc.com, the technical contact listed on Sunoco's website):

You're on the right track. Basically, there is no link. Octane and
flame speed are related to composition, not each other. A certain
octane does not dictate a certain flame speed.

Mike / Sunoco

 

[FlorIdaho Chris]

Does anyone have experience using Aviation 100LL in their cars? I have a tanker trailer of the stuff at my house for..ah..other purposes and am thinking about running it in the TT Camilo/Heffner car. Thoughts?

 

[BlackICE]

I have read that AV gas shouldn't be used in cars because is is designed for lower temperature operation in airplanes, thus has a lower vapor pressure that is not optimal for cars, unless you drive during the winter time in MI, or ID. Definitely not good for FL :lol

 

[Tipo874]

100LL is Low Lead not No Lead so I wouldn't run it with a catalytic convertor or in a state that still does the swab test for emissions to test for the presence of lead in the filler neck if any state still does that.

 

[FlorIdaho Chris]

No cats. And, Idaho is a free state. We don't believe in no federally mandated emissions BS. Hell, most folk don't even pay taxes. :lol

 

[BlackICE]

Hell, most folk don't even pay taxes. :lol

Now I thought that was in FL. At least when it comes in state income taxes.

 

[bonehead]

Running 1/2 mile roll-on races this Saturday in Coalinga (for those in CA, you may know of it because of Harris Ranch). Stock except the rear exit headers. Going WOT hopefully many times down the runway in 90 degree weather. I have a 5 gal pail of VP MS109 that I have stored in my garage. Any real benefit in using it? Not looking for more power, just more insurance against detonation. Any downsides?

 

[Mullet]

Running 1/2 mile roll-on races this Saturday in Coalinga (for those in CA, you may know of it because of Harris Ranch). Stock except the rear exit headers. Going WOT hopefully many times down the runway in 90 degree weather. I have a 5 gal pail of VP MS109 that I have stored in my garage. Any real benefit in using it? Not looking for more power, just more insurance against detonation. Any downsides?

Put it in the tank, it can't hurt

 

[BlackICE]

Running 1/2 mile roll-on races this Saturday in Coalinga (for those in CA, you may know of it because of Harris Ranch). Stock except the rear exit headers. Going WOT hopefully many times down the runway in 90 degree weather. I have a 5 gal pail of VP MS109 that I have stored in my garage. Any real benefit in using it? Not looking for more power, just more insurance against detonation. Any downsides?

Without a tune it might even go a little slower. For insurance use putting 1/2 to all of the 5 gals into a tank of gas will lesson the chance of detonation, but since your car has a completely stock drive train and tune, even that is probably not needed. The OEM Ford tune is conservative and you shouldn't have any problems running it with pump gas.

 

[Vince H]

Running 1/2 mile roll-on races this Saturday in Coalinga (for those in CA, you may know of it because of Harris Ranch). Stock except the rear exit headers. Going WOT hopefully many times down the runway in 90 degree weather. I have a 5 gal pail of VP MS109 that I have stored in my garage. Any real benefit in using it? Not looking for more power, just more insurance against detonation. Any downsides?

Look at this guy. I like it Ed. I hope you have some great runs.

Vince H

 

[bonehead]

Without a tune it might even go a little slower. For insurance use putting 1/2 to all of the 5 gals into a tank of gas will lesson the chance of detonation, but since your car has a completely stock drive train and tune, even that is probably not needed. The OEM Ford tune is conservative and you shouldn't have any problems running it with pump gas.

This is one of the things I'm concerned about. Why does this occur?
The concern with detonation is only because although we technically get '91', gas all over CA is generally sh*t. Who knows what the actual octane rating may be......

 

[BlackICE]

This is one of the things I'm concerned about. Why does this occur?
The concern with detonation is only because although we technically get '91', gas all over CA is generally sh*t. Who knows what the actual octane rating may be......

I was told by some Ford engineer since the car doesn't have any knock sensors, it is tuned so that it even can run on 87. Now I wouldn't try that and pound on the car.

Higher octane gas burns slower so running higher octane gas with a stock tune the may move the optimal peak cylinder pressure to a less favorable crankshaft position, yielding lower torque and horsepower.

 

[bonehead]

I was told by some Ford engineer since the car doesn't have any knock sensors, it is tuned so that it even can run on 87. Now I wouldn't try that and pound on the car.

Higher octane gas burns slower so running higher octane gas with a stock tune the may move the optimal peak cylinder pressure to a less favorable crankshaft position lower torque and horsepower.

I wouldn't park my car with 87 in the tank much less WOT it down a runway:eek

Thanks for the thermodynamics lesson. Maybe I won't use it. I'll already be one of the slowest cars on the grid. Don't want to handicap myself further.

 

[BlackICE]

I used to add a few degrees for timing advance and put 5 gals of Sherwin Williams gas into a tank for off road events. :lol

Too bad CA outlawed the sales of the stuff. Now you have to go to NV to buy it.

 

[PL510*Jeff]

Dyno guys do this all the time. With no tune changes. Helps to compensate for heat gain.

 

[Fast Freddy]

Running 1/2 mile roll-on races this Saturday in Coalinga (for those in CA, you may know of it because of Harris Ranch). Stock except the rear exit headers. Going WOT hopefully many times down the runway in 90 degree weather. I have a 5 gal pail of VP MS109 that I have stored in my garage. Any real benefit in using it? Not looking for more power, just more insurance against detonation. Any downsides?

that fuel is oxygenated and will lean your A/F ratio out 2%. but on a stock car like yours the computer should be able to compensate for it....

 

[BlackICE]

that fuel is oxygenated and will lean your A/F ratio out 2%. but on a stock car like yours the computer should be able to compensate for it....

The ECU runs open loop under boost so no O2 sensor compensation, but the stock tune does have learning turned on that it applies what is learned during closed loop to the fuel tables open loop cells. So if you drive a while it should learn and correct WOT too.

However that doesn't matter because the stock tune's a/f is in the 10.X range at WOT.

 

[GTED]

Without a tune it might even go a little slower.

That is true, ask me how I know
At one of our fine GT Speed Days, I had a tankful of 100 octane, but I accidentally loaded the stock tune, instead of the proper tune that matches the gas...... Every GT had a same/similar pulley and tune reached between 200.xx to 205.xxmph, except for me After 16 runs, my best was 198.7mph...... My goal was to touch 200...., sigh.

GTED

 

[BlackICE]

That is true, ask me how I know
At one of our fine GT Speed Days, I had a tankful of 100 octane, but I accidentally loaded the stock tune, instead of the proper tune that matches the gas...... Every GT had a same/similar pulley and tune reached between 200.xx to 205.xxmph, except for me After 16 runs, my best was 198.7mph...... My goal was to touch 200...., sigh.

GTED

You will get the 200+ during your next Mojave event.

 

[Jason Watt]

What fuel for a TT setup with high boost??

Hi gentlemen.

Need your advice please...

I'm street racing 2 GTR's with in excess of 800HP very soon :eek

So I'm wondering what fuel to use.
I'm running TT's and plan to run 21psi boost on race gas - but what to choose??
I'm great friends with the Sunoco dealer in Denmark and they have suggested two:

260 GT Plus (unleaded): http://www.racegas.com/fuel/20
MaxNos (leaded): http://www.racegas.com/fuel/15

I know that leaded fuel is hard on the O2 sensors, but would it be OK for a limited time??

:cheers