Fuel additive mumbo jumbo

With the 2022 season upon us I've been looking into testing out a fuel additive to potentially keep the engine from blowing up from extended track use. The subject I plan on using is a 1990 Ef Civic with a Integra GSR swap. It has a great tune and I've never felt any pinging but i think a slightly higher octane rating could only help out.

My question everyone is what are some recommendations on fuel additives/ adding race gas or methanol to your tank? This car is my daily and i can't have a standalone racing fuel system. I've seen people recommend adding straight meth to their tank but I'm curious as to wether it'll burn the fuel pump BUT it is the cheapest option by far. Fuel additives like Torrco and boostane look appealing but get expensive where i could buy a 5 gallon can of 110 and mix it that way for much cheaper.

All the info you guys got lay it on me

I would just tune the car for whatever octane is readily available. The difference between 91 and 93 is negligible. 

And if it's that on the limit, I'd sacrifice a few HP to make the tune less on the ragged edge. No one wins HPDE. 

I'm a bit confused about what you're trying to do.  You're not pinging, but you think a "slightly higher octane rating could only help out"?  Do you have a knock sensor?  If you're on the edge of detonation on the street such that you think the track will put out over it, chances are good you're going to be pinging on the street climbing a hill on a hot day, too.

Any 110 octane race fuel is leaded, which will promptly destroy your catalytic converter.  And since it's your daily driver, you're a responsible human with a catalytic converter on the street, right? If you really want higher octane than whatever's available, you're probably on the right track with mixing 100-octane unleaded race fuel.

In reply to Berck :

The tune i have is on the safe side already and the track use i have done now has only showed timing being pulled at extremely high temps. I've been reading in other forums that track guys just put in some racing fuel or additives to make sure they're farther on the safe side from not. I'm not sure if it's worth it or helps for long term reliability hence why i am consulting the gurus here lol

In reply to z31maniac :

Yeah that's what i thought too, my only question i guess is if it would increase the lifespan of the motor in the long term. Kinda like cheap insurance

Got it, that makes sense.  If the goal is to make sure you don't pull timing on the edge cases, mixing some unleaded race fuel is probably the simplest and safest way to go, but the stuff isn't exactly cheap.  I've also had good results mixing in toluene on an old detonation-prone motorcycle that really wanted leaded gasoline, but it didn't have a catalytic convertor, and I'm not sure if toluene is cat-safe.  On the same motorcycle I tried the various readily-available "octane boosters" which didn't do anything for the detonation, but did coat my spark plugs in some pretty foul red residue.

We've been regularly writing about gasoline for a few years now.

Start here: Adding Additives

Once there, you'll find links to more articles that should help regarding octane, ethanol and much more. Good luck!

In reply to Berck :

Yeah race gas definitely isn't "cheap" haha, but I know it's cheaper than a new motor. I have a test pipe i can bolt on and off in a matter of minutes so i think I'll try and pick up some race gas from a pump i have nearby. I'll have to report back in a few months with some data to see if it really did anything. Thank you for the insight!

In reply to David S. Wallens :

Thanks! I'll look into these as well!

junkc4 said:

With the 2022 season upon us I've been looking into testing out a fuel additive to potentially keep the engine from blowing up from extended track use. The subject I plan on using is a 1990 Ef Civic with a Integra GSR swap. It has a great tune and I've never felt any pinging but i think a slightly higher octane rating could only help out.

My question everyone is what are some recommendations on fuel additives/ adding race gas or methanol to your tank? This car is my daily and i can't have a standalone racing fuel system. I've seen people recommend adding straight meth to their tank but I'm curious as to wether it'll burn the fuel pump BUT it is the cheapest option by far. Fuel additives like Torrco and boostane look appealing but get expensive where i could buy a 5 gallon can of 110 and mix it that way for much cheaper.

All the info you guys got lay it on me

Don't use methanol.  It's nasty stuff that can and does kill people. On the other hand pure Ethanol is safe enough to drink.  It's what is in wine beer and booze. 
  Ethanol also has 114 octane.  Plus it cools the engine.   And adds horsepower.     Not to mention it cleans the combustion chamber. 

 Any car newer than 2001 can safely use 15% (E15) ethanol without any changes. And any car ever made can use 10% ethanol. (E10) 
      85% ethanol (E85) does require a change to the tune.  But will add about 10% more power*.  
      * pump grade E85 varies between 53% and 85% ethanol. Holley ( the carb people ). Has a $22 tester so you know what you're getting.   Or you can just buy it from a race gas supplier. 
    Indy race cars use 100% ethanol while NASCAR  uses 15% ethanol.      
     Ethanol and methanol are both alcohols. ethanol has 114 octane while methanol has 116 octane. Methanol is cheaper than ethanol.   But as I said earlier don't use methanol.
       Look at the protective clothing required to be worn when refueling NHRA cars. Mask so you don't breathe the fumes, aprons and rubberized gloves & booties  so splashes don't get on your skin. A face shield so you don't get it in your eyes. 
Methanol is usually made from coal while ethanol is made from grapes, corn and other grains.  

      Methanol is also destructive to many things fuel lines, plastics, gasket materials and ferrous metals like aluminum and brass. 
  Ethanol doesn't have any of those traits. 
Any alcohol will absorb moisture. However a little water actually is good for your engine.         ( notice how much smoother and more powerful your engine is in the rain?) assuming your ignition is in good order!  
      But if you leave alcohol  in your gas tank for more than a month the humidity in the air will be absorbed by the fuel vent in your car.   How much?  Well 10% ethanol can absorb 10% water ( 100% saturation)*over a very long period. Over a long enough period  the water can cause rust in your tank.  But any gas even non oxygenated gas will slowly evaporate the lighter ends of the fuel chain.  The parts that make starting easier.  
   *  If you have a 20 gallon gas tank and you fill your tank with E10  you have 2 gallons of ethanol. Don't worry though,  it won't overflow. The fuel vent will be evaporating fuel at about the rate  it's absorbing water. 
     

In reply to frenchyd :

I purchase it from a race gas supplier for tuning, then run a flex fuel sensor to adjust the map from the parameters of the E85 and 93 maps based on ethanol content. 

The trouble with ethanol is that these days you're invariably starting with E10 which doesn't leave any room to add more.  If you have ready access to ethanol-free 91/93, you can splash in some E85 and get a little higher, I guess? 

I do play that game, though... In my Focus RS, if I happen to fuel someplace that has E-85 available, I'll add a gallon of E-85 with a tank of 91 E-10, which should get me close to 93 octane E15, since 93 isn't available here in Colorado.  Not that I can tell the difference, but theoretically the car can make use of 93, and it's slightly cheaper, so why not?

In reply to frenchyd :

Are you able to add straight ethanol to a tank of 93 gas without a re-tune? If so what measurements for the mixture am i looking for?

In reply to Berck :

Ah just saw this after i replied to Frenchy. So if i can't raise the ethanol content safely by mixing ethanol in my only real option is to raise the octane level with race gas....right?

Berck said:

The trouble with ethanol is that these days you're invariably starting with E10 which doesn't leave any room to add more.  If you have ready access to ethanol-free 91/93, you can splash in some E85 and get a little higher, I guess? 

I do play that game, though... In my Focus RS, if I happen to fuel someplace that has E-85 available, I'll add a gallon of E-85 with a tank of 91 E-10, which should get me close to 93 octane E15, since 93 isn't available here in Colorado.  Not that I can tell the difference, but theoretically the car can make use of 93, and it's slightly cheaper, so why not?

Perhaps you just said it wrong?  There is non oxygenated fuel available most places. So that's E zero.   
     If you have a flex fuel option on your car you can add whatever  gasoline you want and the cars computer will adjust the timing and fuel air mixture automatically based on what you put in. E85,  91 octane non oxygenated , 87 octane E10, whatever. Mix and match. 
    However without that $99 option ( and the required sensor) you can't access the program that allows the flex fuel programs to work. 
  Plus pump E85 will have between 53% and 85% ethanol.  So unless you have Holley's $22 ethanol test or you don't know what you have. 

In reply to junkc4 :

Cool. Lots of good info in there from a real fuel engineer. 

Your tune is almost certainly good for E10, and that's probably what you're running. I have no idea if you're good for E15 or higher.  If you're starting with E10 and you can only go up to E10, you can't add more.  If you find some ethanol-free 93, you can safely add some E85.  Unfortunately, like frenchyd said, without testing it, it's basically impossible to know how much ethanol is *actually* in E85.  But if you just want a little more octane and you can run E15, this might be the cheapest way to go.

frenchyd said:

Perhaps you just said it wrong?  There is non oxygenated fuel available most places. So that's E zero.   

I don't know about "most places", but it's pretty hard to find here in Colorado.  There's only one in the entire Colorado Springs metropolitan area.  Other places in the country seem to have it available on every corner...

So it seems the moral of the story is i should either convert the system to flex fuel to run e85 or add some race gas to raise the octane where it needs to be to prevent knock. I have learned more about fuel than i thought i ever would haha! Chances are the change in octane or ethanol content I'll still probably blow the motor some other way lol but  Thank you to everyone for their knowledge i got a new winter project to tackle now!

junkc4 said:

In reply to frenchyd :

Are you able to add straight ethanol to a tank of 93 gas without a re-tune? If so what measurements for the mixture am i looking for?

I don't know where you'd get 100% ethanol from.  That would be 200 proof booze. And treated  accordingly.    
    I'm not in any sort of position to tell you how to tune your car.  
 But if you're asking if ethanol will mix with gasoline, the answer is yes.  

Berck said:

frenchyd said:

Perhaps you just said it wrong?  There is non oxygenated fuel available most places. So that's E zero.   

I don't know about "most places", but it's pretty hard to find here in Colorado.  There's only one in the entire Colorado Springs metropolitan area.  Other places in the country seem to have it available on every corner...

I'm sorry your neighborhood doesn't offer non oxygenated fuel.  Lawn mowers and other yard equipment seem to need it as do boats.  

Blending race gas can be a crapshoot as you need to have a consistent level before you add a consistent amount. Back when we would drive the drag cars to the track we may even go as far as draining it all out first. But if you tune for pump fuel on E and 5gal of a 98oct unleaded race and always start with it under E you would be safe from a tuning perspective. 

Also, frenchy hates on methanol too much, it's amazing compared to the degreaser most cars run on.

junkc4 said:

So it seems the moral of the story is i should either convert the system to flex fuel to run e85 or add some race gas to raise the octane where it needs to be to prevent knock. I have learned more about fuel than i thought i ever would haha! Chances are the change in octane or ethanol content I'll still probably blow the motor some other way lol but  Thank you to everyone for their knowledge i got a new winter project to tackle now!

GRM tested race gas and various other fuels including ethanol. Look it up for best advice.  What I remember is race gas only added a couple of hp. At a risk to your catalytic converter.  Ethanol doesn't hurt that. 

junkc4 said:

So it seems the moral of the story is i should either convert the system to flex fuel to run e85 or add some race gas to raise the octane where it needs to be to prevent knock. I have learned more about fuel than i thought i ever would haha! Chances are the change in octane or ethanol content I'll still probably blow the motor some other way lol but  Thank you to everyone for their knowledge i got a new winter project to tackle now!

Nope. Seriously, the best option is to get a retune that isn't so on the ragged edge it needs to pull timing during a session. 

That's really the best option vs trying to go Flex Fuel (do your current pump and injectors have enough headroom for the ~30% more fuel E85 will use, and you're still going to need a retune for that), or additives, or trying to blend race gas. 

Some more reading from the archives that might help:

E85 Ethanol Fuel: How to Corn Your Way to More Horsepower

Why not Methanol?

Does all E85 fuel contain 85% ethanol?

Is a Water/Methanol Injection Kit the Tuning Aid You Need?

Fuel shootout