C 12 side note
 

The c12 fuel I ran in my car this weekend at mission was from last July when I bought it for Woodburn. I had half a tank sitting in the car since then, and 3 plastic 5 gallon jugs sitting under a tree in my back yard out in the elements. all this fuel tested perfectly every time.

Re: C 12 side note
 

I ran the first race this year on left-from-last-year C11. It had been in the plastic jugs in my trailer over the winter. Checked perfectly, "right in the middle" they told me. Never a problem with C11.

Re: C 12 side note
 

Only problem with C-11 is the price! Lower octane, yet cost more than some of the higher octane fuels.

Re: C 12 side note
 

Darren, in my car it's a tad faster on C11 after adding about 5% WOT air/fuel. More octane than you need costs a little power. Of course, in slow down mode that doesn't matter. :-)

Re: C 12 side note
 

Isn't C-11 a little quicker burn rate than C-12? No?

Lower octane doesn't hurt as long as you are not detonating. A quicker burn rate is....well....quicker.

I can see how C12 would check ok in Mission. I think it has a harder time in the heat of our area if not properly stored. And sometimes it will be marginal right out of the drum.

This also may be due to their testing equipment at the tracks.

Re: C 12 side note
 

C11 has a much lower specific gravity than C12. The lower the specific gravity the faster it burns. Faster burning means more power. You aren't paying for octane you are paying for the properties that make it have a lower specific gravity.

Re: C 12 side note
 

Thanks for the explanations guys.
Specific gravity
C-11 .710 @ 60* F
C-12 .717
C-14 .696
C-16 .735
C-25 .695
At No Problem Raceway for the D4 race C-11 and C-16 were $16.00 per gal. and C-14 was $14 per gallon. Sorry for getting off the original topic. I do run C-11 with no problems at fuel check as of yet, but I'm new to this super stock stuff. Maybe I should try some C-25, I could use all the help I can get.

Re: C 12 side note
 

How is it that most everyone passes and only a few fail? If the testing equipment was bad wouldn't everyone fail?

Re: C 12 side note
 

This is based on my experience at the fuel check in Div 4. I use C11 in my stocker and C12 when I drive our Calais super stocker. Without question C12 was the one that would come up bad from the others being checked. And many of the comments would be "I just got it off the truck.."

The testing equipment looks like something from the 80's. Maybe it isn't that critical, but I am not the first to question how up to date their equipment is.

Re: C 12 side note
 

The real problem is the way the testing process is set up. To be clear the parameters or window that the fuel is suppose to test within.

When I've been close to failing fuel check it's always been on the low side. A few years back at Sonoma many of us were close to failing or failing.

I went and bought a fresh 5 out of a new drum. They tested it for me and said it was perfect, right in the middle. Why if when we fail it's always on the low side, but when the fuel is fresh it only starts out life in the middle?

Shouldn't it start out life at the top of the scale???

Re: C 12 side note
 

Doesn't seem to work that way. I had a jug of C11 checked at Mission last weekend from the bottom of a 2 year old drum, was told it was right in the middle. The fuel in my car was out of a fresh drum, apparently it was right in the middle too.

Jim Mantle V/SA

Re: C 12 side note
 

BTW, what's the average price of C12 these days?

Are you saying that C12 might have more problems in testing than C11?

But it might be the equipment...possibly not being the same...or calibrated to a
specific standard?

Re: C 12 side note
 

Just bought some in sealed 5 gallon cans. $60 per can or $12/ gal. Never had either 11 or 12 fail. More issue with non VP fuel as the NHRA guys don't seem to like you using the other fuels. So I have been using C12 lately

Re: C 12 side note
 

All fuel checks rely on proper handling and test procedures to be accurate. Things such as ambient air temps, beaker temps, contamination from the air or from equipment that hasn't been cleaned, calibrations that haven't been done or haven't been done properly.
And there are some brands of race gas that, although they advertise consistency, aren't really as consistent as they need to be batch to batch. Sometimes they won't pass even right off the truck.
Just be sure fuel samples are taken with great care, keep the samples out of direct sunlight at all times, and make sure the tested temperature is correct.

Re: C 12 side note
 

When I worked for NHRA in the 80's I said the same thing. If the fuel tested on the low side most of the time you slow down. If it tested high then you should be DQ'ed. Throw out the low side test!!!!,

Re: C 12 side note
 

Did the cost of c-12 go up all over or just here in cali,i just payed 80.00 bucks for a 5 gallon can or 16.00 bucks a gallon.