Mixing Different Octanes...
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 7,820
Likes: 0
From: Burlington ON
Cruise-In I, II, III, IV & V Veteran
CI-I & II Auto-X Champ
Mixing Different Octanes...
Does anyone know the formula to figure out what total octane you will get when mixing certain amounts of one octane fuel with another?
Say I mix 5 gallons of 110octane with 10 gallons of 94 octane, what would the octane rating of the mixture be?
Would it be (94 * 2/3) + (110 * 1/3) ??
Is there a chart anywhere on the net for this type of thing?
Thanks in advance!
Say I mix 5 gallons of 110octane with 10 gallons of 94 octane, what would the octane rating of the mixture be?
Would it be (94 * 2/3) + (110 * 1/3) ??
Is there a chart anywhere on the net for this type of thing?
Thanks in advance!
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 7,820
Likes: 0
From: Burlington ON
Cruise-In I, II, III, IV & V Veteran
CI-I & II Auto-X Champ
Re: Mixing Different Octanes... (LG Motorsports)
Thanks Lou...
So I take it my (2/3 * 94) + (1/3 * 110) equation was correct...
So I take it my (2/3 * 94) + (1/3 * 110) equation was correct...
Drifting
Joined: Jul 2002
Posts: 1,613
Likes: 0
From: Spring Tx
Re: Mixing Different Octanes... (Flyin'Brian)
Those formulas only work with mixing two different unleaded fuels. Since 110 octane normally has tetrethyl lead in it , your octane will be much higher. It was explained to me by a petroleum engineer, that free molecules of the lead will raise the octane of the unleaded without degrading the octane of the leaded fuel. I saw the actually results that were done on the octane engine at the lab at the Arco refinery in Houston.This was done a number of years ago before 87 octane leaded regular was phased out.
Premium Supporting Vendor
Joined: Oct 2001
Posts: 8,392
Likes: 572
From: Dallas Tx
St. Jude Vendor Donor '03-'04-'05-'06-'07-'08-'09-'10-'11
Re: Mixing Different Octanes... (MattG)
Yes Matt, You get the extra credit.
It is just like figuring your average in High school. You got 2 tests at 94 and then 110 on another. (must have been that extra credit).;)
So 94+94+110=298 divided by 3=99.3 It must have been a test on ratios.
LG
It is just like figuring your average in High school. You got 2 tests at 94 and then 110 on another. (must have been that extra credit).;)
So 94+94+110=298 divided by 3=99.3 It must have been a test on ratios.
LG
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 7,820
Likes: 0
From: Burlington ON
Cruise-In I, II, III, IV & V Veteran
CI-I & II Auto-X Champ
Re: Mixing Different Octanes... (LG Motorsports)
Thanks for the clarification Lou! Math never was my strong point! :D
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
Le Mans Master
Joined: Jan 2001
Posts: 5,786
Likes: 6
From: Lafayette Colorado
Re: Mixing Different Octanes... (MattG)
How bad would it be on the O2 if one mixed 13 gallons 91 with 3 gallons of 110 unleaded? I know lead fuel can gum up the sensors, but how long woul dthey last with this combo? TIA.
Drifting
Joined: Jul 2002
Posts: 1,613
Likes: 0
From: Spring Tx
Re: Mixing Different Octanes... (kromberg)
I've only tried that once, and don't recall a problem with the O2 sensors, but the lead plugged up the cats in short order. Created so much back pressure that the cats were vibrating against the floor boards.There is no doubt that 91 is costing you a bit of power, but if I couldn't find 100 unleaded, I wouldn't mess with it.
Drifting
Joined: May 2002
Posts: 1,607
Likes: 1
From: San Francisco CA
Re: Mixing Different Octanes... (MattG)
Another way to calculate it with 5 gals of 110 and 10 gals of 94:
(5 gals/5+10 gals) x (110 octane – 94 octane) + 94 octane = 99.3333333
If you had 10 gals of 110 and 5 gals of 94:
(10 gals/5+10 gals) x (110 octane – 94 octane) + 94 = 104.66666
There’s a formula in there someplace ;)
(5 gals/5+10 gals) x (110 octane – 94 octane) + 94 octane = 99.3333333
If you had 10 gals of 110 and 5 gals of 94:
(10 gals/5+10 gals) x (110 octane – 94 octane) + 94 = 104.66666
There’s a formula in there someplace ;)
Premium Supporting Vendor
Joined: Oct 2001
Posts: 8,392
Likes: 572
From: Dallas Tx
St. Jude Vendor Donor '03-'04-'05-'06-'07-'08-'09-'10-'11
Re: Mixing Different Octanes... (TeamZ06)
Lets see, 10 gal/5gal= 2/1 Looks the same to me.
As you can see, I reduced the gallons to a 2 to 1 ratio to simplify.
Now, if you had 9.27 gal of 94, and 4.89 gal of 110, there is no easy ratio, so it makes sense to do it longhand.
And the answer is?????
(all homework must be in writing, and on official Corvette Forum letterhead. All those in noncompliance will be scored accordingly.)
LG :D
Melting Slicks
Joined: Feb 2002
Posts: 2,290
Likes: 1
From: Ca
Re: Mixing Different Octanes... (vetterdstr)
Lou, I wish we had 94 here!! :cry :bs
vetterdstr :cheers:
vetterdstr :cheers:
Racer
Joined: Jul 2000
Posts: 395
Likes: 1
From: Los Altos Hills Ca.
Re: Mixing Different Octanes... (RCswish)
I have been mixing 100 octane unleaded with 91 unleaded for a while. It makes a huge difference in performance. However, I have to drive to south San Jose to get it. Does anyone in the S.F. bay area know of any other sources for the 100 octane unleaded on the peninsula???
Thanks,
Mark
Thanks,
Mark
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
Re: Mixing Different Octanes... (hot1corvette1)
What I use is this 30 gal. Fuel Tank. I fill up this tank with 100 and take it home. This way I can add it to the car as needed without having to drive to the station everytime I need the 100. It come in very handy for the track too.
vetterdstr :cheers:
[Modified by vetterdstr, 7:03 PM 10/10/2002]
vetterdstr :cheers:
[Modified by vetterdstr, 7:03 PM 10/10/2002]
Le Mans Master
Joined: Dec 1999
Posts: 5,169
Likes: 6
From: Greenville SC
Re: Mixing Different Octanes... (MattG)
I guess we are both fortunate and unfortunate here in the south. We have 93 octane as our super, which is good. But I'd LOVE to have 100 octane UNLEADED available for mixing.
What's it cost?
We do have several stations with 99 (I think, it may be higher) Octane LEADED gas, but that does me no good.
What's it cost?
We do have several stations with 99 (I think, it may be higher) Octane LEADED gas, but that does me no good.
Racer
Joined: Jul 2000
Posts: 395
Likes: 1
From: Los Altos Hills Ca.
Re: Mixing Different Octanes... (vetterdstr)
I love that tank! Only problem: I don't have a vehicle that I could use to transport that around, especially when it is full. But, it would certainly solve the problem. I only use about 3 or 4 gallons of the 100 unleaded per tank and that would last a long time. Where did you get it??
Mark
Mark
Racer
Joined: Jul 2000
Posts: 395
Likes: 1
From: Los Altos Hills Ca.
Re: Mixing Different Octanes... (Tom Steele)
Tom,
The 100 unleaded costs about $4.10 per gallon. Pretty steep, but I only add 3 or 4 gallons per fill. So it raises the average cost per gallon to about $2.25.
Still steep, but it makes the car run like it is supposed to.
I have never tried mixing in more than 3 or 4 gallons. I wonder what would happen if I ran a tank of straight 100 unleaded???? Sounds like an interesting experiment as long as it doesn't blow up something.
Mark
The 100 unleaded costs about $4.10 per gallon. Pretty steep, but I only add 3 or 4 gallons per fill. So it raises the average cost per gallon to about $2.25.
Still steep, but it makes the car run like it is supposed to.
I have never tried mixing in more than 3 or 4 gallons. I wonder what would happen if I ran a tank of straight 100 unleaded???? Sounds like an interesting experiment as long as it doesn't blow up something.
Mark