Racing Gas

[shreddr]

This has probably been covered here before, and I know Jony RR was using some rocket fuel mixture in his R11, but has anybody just taken a reasonably stock R12 and ran some racing gas through it to see what the impact is? I was just reading a Cycle World article on Daytona, and they mentioned that the HP2S went from 121 to 128 HP (6%) just with the use of VP MR11 (mystery rocketfuel).

As I consider engine mods, I wonder if I am better off just getting a drum of fuel, and going the simple route. at an extra $4/gallon and at 40mpg i could get about 14,000 miles of added benefit at the same cost of the piston/rod combo, although that combo should change the characteristics of the engine as well, not just an HP boost.

[Fenring]

If it's only higher octane fuel there should be no difference, unless compression ratio is being tinkered with. If it's adding a more energy dense combustibles, there might be an increase of torque and power output at a price of overheating and, ultimately, engine longevity. But I'm not telling you anything new here.

[roger albert]

MR11is good stuff and can easily get you 6% on an aircooled motor with no ohter mods (save jetting, of course), and pushing 8% on a liquid cooled one. Dumping it into and FI bike without mjapping will yield little benefit, and ;possibly a detriment (willl run rich-ish in my experience, at least with that fuel's little brother (MR9) which I use.

It is extremely diminishing returns. I don't know about Mister11, but Mister9 is in NO WAY cost effective vs other engine mods you can use. Not sure where youu get the extra $4/gallon, but it sounds way off. I use the cheaper MR9 and have a killer deal at $25/gallon, which is a BIG price delta ($20 gallon) I know west coast guys paying 30-35/gal. Even at my lower bulk racer price that's 70 gallons(dozen-15 tanks) for $1400. Very shortlived benefit compared to same amount of money on motor mods.

Note, in bigger drums, you can get it cheaper than me (42 or 55gal or some such) but then you hve to have a place to store it. You DONT want it in your garage. And once open, it's crap within 6 weeks, or twice that if optimally stored (temp controlled shed and perfect seal)

In short, I wouldn't go that way.

[roger albert]

MR11is good stuff and can easily get you 6% on an aircooled motor with no ohter mods (save jetting, of course), and pushing 8% on a liquid cooled one. Dumping it into and FI bike without mjapping will yield little benefit, and ;possibly a detriment (willl run rich-ish in my experience, at least with that fuel's little brother (MR9) which I use.

It is extremely diminishing returns. I don't know about Mister11, but Mister9 is in NO WAY cost effective vs other engine mods you can use. Not sure where youu get the extra $4/gallon, but it sounds way off. I use the cheaper MR9 and have a killer deal at $25/gallon, which is a BIG price delta ($20 gallon) I know west coast guys paying 30-35/gal. Even at my lower bulk racer price that's 70 gallons(dozen-15 tanks) for $1400. Very shortlived benefit compared to same amount of money on motor mods.

Note, in bigger drums, you can get it cheaper than me (42 or 55gal or some such) but then you hve to have a place to store it. You DONT want it in your garage. And once open, it's crap within 6 weeks, or twice that if optimally stored (temp controlled shed and perfect seal)

In short, I wouldn't go that way.

[Guest24]

I'm not positive Jeff but i think Nate is running racing fuel in pretty much stock engines. I'm sure the HP2S is stock. Jump in here and correct me if I'm wrong jerry/ralf.

[shreddr]

Originally Posted by roger albert

MR11is good stuff and can easily get you 6% on an aircooled motor with no ohter mods (save jetting, of course), and pushing 8% on a liquid cooled one. Dumping it into and FI bike without mjapping will yield little benefit, and ;possibly a detriment (willl run rich-ish in my experience, at least with that fuel's little brother (MR9) which I use.

It is extremely diminishing returns. I don't know about Mister11, but Mister9 is in NO WAY cost effective vs other engine mods you can use. Not sure where youu get the extra $4/gallon, but it sounds way off. I use the cheaper MR9 and have a killer deal at $25/gallon, which is a BIG price delta ($20 gallon) I know west coast guys paying 30-35/gal. Even at my lower bulk racer price that's 70 gallons(dozen-15 tanks) for $1400. Very shortlived benefit compared to same amount of money on motor mods.

Note, in bigger drums, you can get it cheaper than me (42 or 55gal or some such) but then you hve to have a place to store it. You DONT want it in your garage. And once open, it's crap within 6 weeks, or twice that if optimally stored (temp controlled shed and perfect seal)

In short, I wouldn't go that way.

good to know, i dont recall where i got the $8/gallon, but at $25/gallon race fuel will definately not be in the consideration set, all right lets get back to those pistons and rods!

[shreddr]

an interesting article on fuel comparison I found here:

http://www.smokemup.com/tech/fuels.php

In our everquest for more power we need consider what propels our cars, FUEL. Most hot rodders usually only consider running one type of fuel in their engine, gasoline. This article's intent is to explore some of the other alternative fuels, alcohol, and nitromethane.
Fuel Types:
Gasoline
Alcohol
Nitromethane

Summary


Gasoline - Gasoline is what most of our cars came setup so it's usually what we stick with. Gasoline is a mixture of hydrocarbons. The petroleum distillate fraction termed "gasoline" contains mostly saturated hydrocarbons usually with a chemical formula of C8H18. The air fuel ratio, A/F Ratio, for complete combustion is 14.7:1, stoichiometric. The A/F ratio for maximum power is approximately 12.5:1 - 12.8:1. This means that our engine at max power, 12.8:1, consumes 12.8 pounds of air for 1 pound of fuel. Gasoline has approximately 18,400 BTU/lb . Using the air flow calculator with the default inputs we get our 355 SBC consumes 567.53 cfm @ 6500rpm which is 42.64 pounds of air and consumes 2.89 pounds of fuel. Therefore if we are using gasoline our engine is producing 53,176 BTU's of energy at 6500 rpm.

Alcohol (Methanol) - Alcohol is usually used in the form of Methyl alcohol or methanol. CH3OH is the chemical formula. Methanol burns at a much richer mixture than gasoline does, between 5.0:1 - 6.0:1. That's 5 lbs of air to one pound of fuel. Methanol has approximately 9,500 BTU/lb. Using our 355, example above, SBC consumes 567.53 cfm @ 6500rpm which is 42.64 pounds of air and now at 6.0:1 ratio for Methanol is 7.11 pounds of fuel. Therefore if we are using Methanol fuel our engine is producing 67,545 BTU's of energy at 6500 rpm.

Nitromethane - is a fuel that is used mostly in specialized drag racing classes, "nitro funny cars" and "top fuel". Nitromethane's chemical formula is CH3NO2. The oxygen in nitromethane's molecular structure means that nitromethane does not need as much atmospheric oxygen to burn, part of the oxygen needed to burn nitromethane is carried in the fuel itself. Typical A/F ratio for nitromethane is 1.7:1 and nitromethane has an energy content of 5,000 BTU/lb. Using our 355, example above, SBC consumes 567.53 cfm @ 6500rpm which is 42.64 pounds of air and now at 1.7:1 ratio for nitromethane is 25.08 pounds of fuel. Therefore if we are using Nitromethane fuel our engine is producing 125,412 BTU's of energy at 6500 rpm.

TABLE 1 Fuel Engine Air Flow (cfm) lbs of air (lbs) A/F Ratio Pounds of Fuel (lbs) Energy Content of Fuel (BTU/lb) Total Thermal Energy (BTU)
Gasoline 567.53 42.64 12.8:1 2.89 18,500 53,176
Methanol 567.53 42.64 6.0:1 7.11 9,500 67,545
Nitromethane 567.53 42.64 1.7:1 25.08 5,000 125,412

Summary - As you can see from table 1 above the clear winner is nitromethane. But that doesn't mean to go out and pour nitromethane in your car and see how it runs, if you do your engine will surely blow up. Nitromethane is very expensive and dangerous to handle. The interesting alternative to gasoline is Methanol. Methanol will make more power, typically around 20% more power than a similar engine running gasoline. Some things to consider in running methanol is your fuel system will have to be completely changed / upgraded. Based on the table above the fuel system will have to flow approximately 2.5 times as much as the gasoline engine.

I guess the old saying is true. "Gasoline is for washing parts, alcohol is for drinking and nitro is for racing."

The most interesting thing for me is the energy density per pound of gasoline at almost 4 times nitromethane! The reason you get so much power out of nitro is that you can run 10 times the amount per unit of air, than you would of gasoline. kind of scary if you thought you would power up your fuel by adding nitro, and all you would do would be diluting the gasolines power unless you SIGNIFICANTLY richened it.

[roger albert]

Good conclusions.

[Fenring]

So, basically, what you really need is a turbo charger.

[roger albert]

Or any cheap used sport bike for 3000 bucks

[Bob Hancock]

I think the stuff some racers (Nate at one time as I recall) use must be drained after the race....can't sit around in the bike while it's down for the week. I'm not sure but think this is a corrosion consideration. I've heard it described as "nasty stuff". Roger.....this sound right?

[roger albert]

U4.x NEEDS to be drained. MR9 says it does, but many leave it in w/o trouble.
They are all nasty. Aromatics. They do nothing to prolong ones life.
I kinda like the smell of MR9 though.
A tiny bit goes a LONG ways. And your tank will still smell like it a dozen tankfulls later.
I spilled one drain/vent line's worth a while back and a girl I know has declined any more BBQs out there for 6 weeks and counting.

good times

[Guest24]

Careful Roger, sniffing race fuel may be hazardous to your wallet. I like the smell of the two-strokes.

[roger albert]

It has already been a hazard to my wallet.
As luck would have it, my two classes with race fuel netted a stupid 2nd and 3rd this weekend.
The bike on pump gas won its class. Go figure. Grrrr.

[JonyRR]

I've never advocated running any nitromethane additive without carburetor jetting or EFI mods.
IF you have the skills/tech to do so, there ARE nitromethane based additives out there that will pull significantly more power over even race fuel...race fuel does pull a bit more power but it's biggest advantage is stable octane and blend so you can get predictability from your fuel.
When I ran a nitro additive such as Price Fuels max Race (40% nitro, 60% casoline blender by volume) in my Beemer, I had the 02 sensor pulled (nitro will poison and 02 sensor) the CCP yanked and ran staight off the Vanderlinde chip....2 heat range colder plugs, a 1% mixture (by volume) in the tank and pray. It didn't scatter, the plugs came out reasonably OK..better throttle response.

My HD dirttracker has two completely jetting schemes..one for pump premium, one for MR9 and a 10% by volume max race load.
it's jettted WAY!!! richer for the good stuff and the difference is night-and-day.
Key phrase here is WAY!!! (as in 6 main jet sizes, one pilot jet size and a way richer needle). jet for plug color and throttle response.
I've scattered hard parts in the past playing with this stuff....and you WILL as well, if you play with the real thing, but I just luuuuuv that nitro smell and the people behind you will be gagging and choking from the fumes...hehehehe.

[Bob Hancock]

If your bike is still under warranty and you try this stuff and chuck a hard part into a passed cars windscreen, can you get BMW to pay for it?

[roger albert]

Hmmm,

the guy that's beat me the last two races always starts much weaker than me, meaning I'm ahead for anywhere from 1/3 to nearly the full race (blew it on the last lap the time before last -- grrrr) Are you saying my exhaust would choke him?

hmmmm