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Having run a shifter for the last 3 years I know exactly what fuel I need to use to get the best out of the engine, now we are running TAG I am wondering what fuel everybody is using? It seems to me that you would want to run as low an octane as possible? But pump gas is so unreliable.
Also can some one explain to me what oxygenated fuel was being run at IMI in TAG senior? was this a mistake or some kind of deliberate fuel tampering? Is it possible this will lead to spec fuel for TAG at CSC events?
@Jon Betts wrote:
Also can some one explain to me what oxygenated fuel was being run at IMI in TAG senior? was this a mistake or some kind of deliberate fuel tampering? Is it possible this will lead to spec fuel for TAG at CSC events?
From VP site:
All VP fuels are available in 5- (19 liter), 15- (56 liter), 30- (113 liter) and 54-gallon (204 liter) pails and drums except where noted.NEW! U2
Designed for stock and modified 2-stroke applications. Makes up to 6% more power than pump gas and any basic nonoxygenated racing fuel. Passes fuel rules for AMA amateur racing, and is also perfect for club level racing, CCS, WERA and AFM. Makes engines faster and more responsive without harming the carburetor, O-rings or gaskets.? Color: Clear
? Oxygenated: Yes
? Motor Octane: 101
? Specific Gravity: .717 at 60? F😯
I don’t know who else’s fuel was found to be hot but I’ll explain my situation. We had been to the track on Saturday and had asked Bobby if fuel was going to be a tech item for the race. Bobby said that there would be no fuel tech so we decided to run some of our leftover practice gas from a few weeks earlier.
This was Sunoco 93 octane pump gas which is sold at a local gas station in Loveland. After qualifying when the announcement wasd made that fuel was going to be tested we went and found Brad to see if we could have our fuel tested, after telling him what I was running he said that he thought my fuel would be fine but would setting up his tester so we could check to be sure. He got the tester set-up after the pre-final and we tested a sample of the fuel. He tested it the first time and found it to be legal, so I thought everything was fine. After a short time Brad came back to us and said that he had mis-calibrated the tester and wanted to re-check our fuel, upon rechecking he found the fuel to be a few points over the legal range of the tester. If I had known that the 93 Sunoco was hot I would have never run it, so we bought some of Brad’s 100 octane gas out of the tank at IMI, and mixed a sample, had Brad recheck it (which was found to be legal), and completely drained and purged my fuel system of the 93 Sunoco and ran the final on Brad’s 100 octane.
As the front page article says the fuel change affected my motor, that is not the case, that was a jetting mistake on my part and not a direct effect of the fuel change. I was simply jetted too lean and could only run the motor at about 1/2 throttle, anymore and the motor would lean out and loose power. For you scepetics out there look at my lap times in the pre-final and final. My fastest laps in each race are almost identical.
From now on we will be buying all of our race fuel at the track to eliminate any further issues for the rest of the CSC rounds.
If we are going to have a fuel tech I think there needs to be a specific proceedure set in place to tech fuels per each motor manufacturers spec. In my opinion there is too much of a variance in manufacturers recommended octane and oil ratio to be able to use only one test sample. Brad himself said that he had been seeing a wide range of test outcomes based on different fuel brand, oil brand, and mix ratio. Again I don’t see how it is possible to enforce a fuel tech based off of only a single control sample.
A big “no” on pump gas…..It will not pass fuel tech with a digitron — I know this from first-hand experience! I was told it failed because of additives like as MTBE, which I think is an oxygenator…..so you might be careful with any fuel that is oxygenated.
I have to agree with Dane on this one. I don’t see how it is possible to control fuels unless it is a spec fuel that must be purchased at the event. There are just too many variances in different types of fuel and especially oils. Some people use synthetic oil and some use castorbean like myself. I don’t see different fuel as an advantage but to try to keep it controlled is kind of unreasonable without a spec fuel.
…..Just my 2 cents!….. :idn:i say VP MS98 for ICC’s, Animals, Tags, etc etc, and C12 for moto engiens, both burn RC3 castor (ecept for 4 cylces odviously) and we wont have this problem
skusa and stars have this, you burn their oil, thier gas, and you dont worry about all this variationIf you want to test fuel, you need to get the three tracks to agree what fuel they will have on hand and test to that along with a specified oil and ratio. The other option is to have PARC FERME. Last but not least don’t tech.
I run pump gas in my Rotax.
Never had any noticible detonation. Up here, you really don’t need to run as high of octane levels as people do at sea level. Especially with a TaG motor, where the ignition is fixed, unlike a shifter where you could advance timing and make use of 100+ octane fuels.
Now that I am back at my computer I will throw my 2 cents in the game. Pump fuel is illegal on every track and that is pretty obvious mistake….but to Dane’s defense we never had testing on fuel last year and that is a good thing since Mike eluded to my uranium enriched fuel in Colorado. 😆
TAG USA RULE
6.0 Fuel
6.1. UNLEADED RACING GASOLINE – of a 98 octane rating by an APPROVED manufacturer.– CITGO RACING FUELS is TAG USATM APPROVED
6.2. OIL – Use of an APPROVED lubricant is mandatory. Ratio is as per manufacturer spec.
– XERAMIC Evolution oil is TAG USATM APPROVED
Tag’s rule is not as concrete as some would like as you can see, but what makes it even more difficult to patrol is the fact that each motor calls for different oil ratio’s and therefore you are going to need a seperate spec fuel tester for each Tag motor. The only real Tag event I was at last year had fuel on site that you had to purchase and could mix it with your own oil to the manufactures spec ONLY. Which meant that rotax had to be run last year at 33:1 even though I ran CSC races at 40:1 Each motor at Rock Island had their own tester to determine that the fuel met spec, but quite honestly I don’t think they really gave a shit because no one was DQ’d for fuel.
Here’s an idea. Why not have each track owner supply the fuel for the races? This gives money to the track owner for supplying the fuel (since they are supposedly losing money to hold races) and takes most of the guess work out of fuel AND if somebody is found guilty of altering their fuel disqualify them for the next 2 races. How do you alter it at the track? Ice, fuel additive or improper oil mixture.
Why not just add the price of 5 gallons of fuel to all CSC race entry fees for all gas classes? You have to buy fuel so why not buy it from the track?
I am a beleiver taht 2 stroke oil and ratios is a very personal thing along the lines of briefs or boxers so just leave the oil and ratio up to each individual competitor.
can the track owners please post the fuels they have available and price?
Thanks Jon
@Jon Betts wrote:
Why not just add the price of 5 gallons of fuel to all CSC race entry fees for all gas classes? You have to buy fuel so why not buy it from the track?
I am a beleiver taht 2 stroke oil and ratios is a very personal thing along the lines of briefs or boxers so just leave the oil and ratio up to each individual competitor.
can the track owners please post the fuels they have available and price?
Thanks Jon
Good idea, but I think filling every single person’s gas jug on race day is going to be a huge pain in the ass.
Also, if someone wants to cheat, they can either put additives in after they buy that fuel, or run a different fuel they brought with them. We are still going to have to test the fuel if we want to enforce these rules.
I’d like to see some proof (dyno chart) that oxygenated fuel actually increases power like VP claims.
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