water injection

[Vinny]

noticed the rule changed this year to specify, no alcohol mix.

 

Does this also include off the shelf windshield washer fluid? Like stuff you buy at advance auto/autozone?

 

Thanks in advance.

[Shawn M.]

noticed the rule changed this year to specify, no alcohol mix.

 

Does this also include off the shelf windshield washer fluid? Like stuff you buy at advance auto/autozone?

 

Thanks in advance.

 

 

Nothing but straight water can be used. Especially since Methanol is the main ingredient in windshield washer fluid.

[Vinny]

most cheap washer fluid is a small percentage of meth. It wont ignite even with direct flame. After all they put it under the hood of every automobile.

 

But ok thanks for the answer. Now to retune.

[gbrown8439]

most cheap washer fluid is a small percentage of meth. It wont ignite even with direct flame. After all they put it under the hood of every automobile.

 

But ok thanks for the answer. Now to retune.

 

Put it under extreme pressure (combustion chamber on the compression stroke), trigger a small explosion and it will burn just fine. If it didn't you wouldn't need a retune because your A/F ratio wouldn't change.

 

If you are allowed any fuel you want I don't see why you would want to inject meth anyway. Water has the ability to dissipate more heat than meth. Most people mix meth in for the octane boost.

[Shawn M.]

If you are allowed any fuel you want I don't see why you would want to inject meth anyway. Water has the ability to dissipate more heat than meth. Most people mix meth in for the octane boost.

 

 

I find that a dangerous comment which unless defined, will be used improperly. So in turn ill post rule #24 from the no points section of the rules that specifies what fuel you can use ect. Its quite helpful for this discussion.

 

24) Fuel: Any grade of commercially available unmodified gasoline or diesel--all octane levels of retail available race gas are permitted. No “home brewed” methanol/ethanol/alcohol mixtures are permitted. Methanol injection systems are illegal. Fuel additives are prohibited. Retail available E-85 is permitted.

[olddragger]

if you are running FI on a high compression rotary engine (10:1) a water meth injection system is mandatory. Since a rotary engine has a 270 degree flame front (recips have a 90) heat control is not an option--- unless you like detonation.

The octane of gas at the pump is unknown now a days--some have more ethanol than others-etc. The small percentage of methanol in WWF helps to guarantee good octane. Which is an absoulute need. WWF is no more than 30-35% meth contrary to what some may think and to get any power from it the engine has to be tuned for it. Most of the time it will actually cost a little bit of power if not tuned. I use it for insurance only.

Meth cools more than the water and water also has an affect on the octane level---believe it or not.

I see no problem with using wwf or a w/m system with a blend of no more than 50/50. Especially in a dyno classed car.

50/50 blend will not burn outside the combustion chamber---guaranteed. I totally understand and agree that a 100% methanol system not be allowed! That is what the rule is referring too---imho?

olddragger

[Greg G.]

if you are running FI on a high compression rotary engine (10:1) a water meth injection system is mandatory. Since a rotary engine has a 270 degree flame front (recips have a 90) heat control is not an option--- unless you like detonation.

The octane of gas at the pump is unknown now a days--some have more ethanol than others-etc. The small percentage of methanol in WWF helps to guarantee good octane. Which is an absoulute need. WWF is no more than 30-35% meth contrary to what some may think and to get any power from it the engine has to be tuned for it. Most of the time it will actually cost a little bit of power if not tuned. I use it for insurance only.

Meth cools more than the water and water also has an affect on the octane level---believe it or not.

I see no problem with using wwf or a w/m system with a blend of no more than 50/50. Especially in a dyno classed car.

50/50 blend will not burn outside the combustion chamber---guaranteed. I totally understand and agree that a 100% methanol system not be allowed! That is what the rule is referring too---imho?

olddragger

 

Well, seeing how the Assistant National TT Director just helped you out by stating the opposite, I think you better go with his interpretation:

 

22) Water injection system +6 (alcohol-water mixtures are not permitted)

 

24) Fuel: Any grade of commercially available unmodified gasoline or diesel--all octane levels of retail available race gas are permitted. No “home brewed” methanol/ethanol/alcohol mixtures are permitted. Methanol injection systems are illegal. Fuel additives are prohibited. Retail available E-85 is permitted.

[gbrown8439]

Meth cools more than the water and water also has an affect on the octane level---believe it or not.

 

Actually, water has the ability to absorb nearly 4 times the heat per given volume that methanol does. Methanol has a specific heat capacity of 1.84 Kj/kg compared to waters 4.187 Kj/kg.

 

Octane by definition is the ability of a fuel to resist autoignition. Since water isn't a fuel it can't affect octane. The affect of injecting water can reduce the chances of auto ignition but it isn't changing the octane of the fuel.

[olddragger]

Oh I accept the rule---no arguement here. I am just the type of person that likes to understand the lodgic behind the rule. And i know there are a lot of smarter people than me out there.

I posted really for the discussion--like to learn from those that know more.

Greg thanks for your reply and you are right--water does have a capacity to lower the temps more in theory, but in practice we have found that the volume needed to address detonation is pretty close to the amount that causes quench. As you know when you inject water it takes up the room your fuel may need. This you cant tune out. You can get too lean if you are not careful--the rotary engine puts out a lot of heat.

 

I will have to respectfully disagree that water doesnt affect working octane. Now the actual chemical octane of course it doesnt but as i understand it , the "working octane", it does. By definition as you have stated it helps the charge from autoigniting. I understand that this happens in 2 ways,

1-by cooling the intake charge temps

2- slowing the flame front development by suppression.

Same affect on autoignition as if you increased your octane except it cools more---right?

 

Now methanol--yep it alters the chemical octane of the charge.

It has less energy than gas per volume so you also have to be careful that you dont replace too much gas with it---or you will lose power also. Does make your sparkplugs look good:)

Now all of this is of course without adjusting the tune to compensate which I cant do anyway.

If I am wrong then I hope others will take time to explain so I can be edumicated-- I actually enjoy learning.

Once again ---not doing a rebel agaisnt the rule, just trying to understand?

OD

[Snowmants]

Have there actually been incidents where Methanol mixtures caused issues at events?

You pour a puddle of Gasoline on the ground and you can light it with a spark.

If you pour a puddle of properly mixed 49%Meth 51% water on the ground you can sit there with a blow torch all day and not ignite it. I can understand an unsafe mixture with high meth content, but not one that is properly mixed into a "non-flammable" classified liquid.

 

My guess--and correct me if i'm wrong--is that the issue is that at events it is hard for race directors/tech inspectprs to tell the difference just by looking, and therefor the only safe thing is to outlaw all such systems. I agree with this as I guess you have to do what you have to do to keep things safe.

[olddragger]

probably no incidents? But you probably hit the nail on the head. I can see where it would be difficult to ensure the correct blend etc, so in the interest in safety not allow any. Makes sense.

Looks like I will have to rejet my system and maybe run a slightly colder plug. Not a real issue.

I wont tell you what I put in the injection tank one time when i ran out of fluid at Roebling Road .

OD

[kbrew8991]

...especially in a car with no additional safety equipment or driver gear required...