UNDER THE SCOOP
Hitting the wall with Oxygenates.

 

I was up on the high banks of Daytona (racing the Rolex 24 hour road course), I've got a pretty good lead in my class so I am just watching the race unfold.   I'm traveling at a pretty good pace (a little over 160 mph) when a faster class GT-1 car (Derhaag Corvette) comes around me on the high side traveling about 185-190 mph as he swings out to take the lead of his class.  Now this is turn four at Daytona and that is a bumpy turn so you need to be really up on the wheel to counter act these bumps or you are gonna hit the wall.  Unless you have a real quality car with a nicely tuned suspension. 

Case in point:  That Derhaag Corvette went over that series of bumps like a Cadillac, with hardly any steering input required.  Well right behind this Derhaag Corvette is the now second place GT-1 car who wants his lead back.  Now this second place car is a nice car but it is nowhere near the quality of the Derhaag Corvette and 190 mph in this following car was a real handful.  It happened.  Right in front of me..the right, the left and wham right into the outside wall he goes as the second place car was upset by this famous series of bumps and the ensuing "tank slapper" shot him right into the outside wall in front of me.  Sheetmetal, tubing and brake ducting flies everywhere.  I avoided what I could, crushed what I couldn't and then prayed I didn't blow a tire as his car slides off the banking in front of me and continues to hit the inside wall in the infield area.

Now just because some other guys car that is very similar to yours can run almost 200 mph at Daytona doesn't mean your car can too.  This racer followed his competitor because he knew he needed to do what he did to at least have a shot at winning his class.   But his equipment wasn't up to the level or at least tuned to the level of the other race car and as a result his race car lay in pieces all over the track.


An in car shot of the carnage at Daytona (from the dash of my Mustang).  Note the car about to slam the inside wall and the rear bumper cover sliding along ahead of me on my left.  Parts scattered down the racetrack are a common occurence in racing and baby steps on a developing program can avoid expensive and deadly incidents.  A few months later a Porsche driver was killed in this very spot when his engine exploded and the car caught fire.  It takes awhile to stop at these speeds and his lungs were overcome with smoke before the car came to a stop.  He never made it out of the car.


Which brings me to the point of the story.

The latest hybrid oxygenated racing Fuels.  If you're vehicle is not of enough quality and you are not capable of tuning your program to the level that these fuels require.  Don't follow that guy into certain disaster. 

Oxygenated fuels for example can make some great horsepower.  They can also blow your engine up if you don't have the tune up or the parts that can take this added power and create some serious consequences that reach beyond your checkbook.

These hybrid fuels just like professionally built race cars, require talented tuners to make them work.  "Pour this in and go up 4 jets and you'll go 2 tenths faster" doesn't mean its gonna happen.  Slow down, get a feel for it, if it feels dangerous get off the throttle or parts are gonna fly.  Thats the lesson.

There are a few bad bits of info flying around concerning these fuels and we'll address some of them now.   

It's been said that a lighter fuel is more explosive and has a higher octane value.  Actually, lighter fuel molecules have lower octane values and many times have lower boiling points.  This increases volatility (early initiation of explosive power), BUT controllable burning becomes more difficult as we need to maintain combustion temperatures and monitor inlet temperature to a finer degree and adjust the program accordingly (adding fuel or altering ignition timing) to stave off detonation.  So unbelievably accurate ignition timing (ie: crank triggers) are almost imperative on high end programs.

"Your ignition timing needs retarded to burn these oxygenated fuels".  False.  It varies. 

Oxygenated fuels use many modifiers to create their effects, some are even using Ethanol as a key blend in this procedure.  You need to be made aware of what is being used to create the oxygenate as some oxygenates have a higher percentage of light ends that burn fast and some oxygenated fuels (like Ethanol blends) will actually move the distillation curve up and burn slower thus requiring more timing.  So just because it is oxygenated, don't assume that its the same.  Get educated from your fuel supplier. There are many ways to create an oxygenate and even more ways to tune an oxygenated fuel.

Fuel hydrocarbons have many classifications and resultant traits:

1. Olefins - known for not being able to resist detonation
2. Alkanes - Octane values usually max out about 100
3. Aromatics - can actually achieve 115 MON

Oxygenates added in fuels typically get higher boiling points and higher heats of evaporation, BUT these variables in types of oxygenates can even get the best fuel supplier confused.  You can talk to a fuel engineer and he can quote you carbon numbers and carbon chain formations and calculate out the numbers for determining burn rate all day long.  But none of that stuff means anything until you get that fuel out on the track and start tuning in YOUR engine.

So if you are going to run on the race tracks with the fast cars, be smart.  Don't go out there pedal down and think a baseline setup is safe enough and is gonna keep your parts from pouring all over the ground.  I've heard of plenty of baseline tuneups "from a buddy that worked on his car" that left parts on the ground seconds after you hit the loud pedal with it in your car.

Consult with reputable tuners before you hit the track and then, when you do hit the track, tune your car to what it is asking for.  Make short bursts and map the changes.  The variances in these fuels we have seen in both jetting requirements and timing needs and ultimately performance are wide.  So be careful.  These higher end fuels are great for some programs, deadly to others and almost all of these oxygenated fuels are highly corrosive so wear gloves and drain the system at the end of every race day. 

Most important: Race the car you have, not the one you're chasing.

Good luck this year and thanks for reading.

Patrick James

 


   

             

 

 

***We are a Florida based LLC.  A 6.5% sales tax will be added to all Florida sales.  Copyright © 2012 Pro-Systems One, LLC..  All Rights Reserved.