Sponsored

Quickest and safest way to go from 87 Octane to 91 Octane

OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Threads
29
Messages
885
Reaction score
661
Location
Las Vegas, NV
Vehicle(s)
2024 JL Willys XR V6
Occupation
Network Architect & Engineer
Also not sure if this is sarcastic. If it is not, STOP WORRYING, go drive your Jeep. Fill it up whenever your heart desires. You will do NOTHING to harm your vehicle. Worse case scenario in about 40K miles you might get some knocking from using 87 octane. Again nothing will harm the engine.
No, not sarcastic. Genuine concern - I am a worrier - it is a big investment.
Sponsored

 

Poffnstuff

Active Member
First Name
Wayne
Joined
Nov 26, 2018
Threads
0
Messages
27
Reaction score
24
Location
So.Cal
Vehicle(s)
18' Wrangler JLU, 18' Ram2500 CC 4x4, 18' FLHXI
Is it safe to run rocket 100 in my car;
ANSWER FROM ROCKET FUEL: It's safe...ish to use on stock engines. The fuel burns cooler and may clog your catalytic converter. Youcertainly won't see any better power or mileage from it, unless you're tuned for 100 octane. It's sold solely for cars that are tuned for 100 octane: race cars and offroaders
 

blnewt

Well-Known Member
First Name
Brad
Joined
Oct 8, 2018
Threads
96
Messages
9,876
Reaction score
23,795
Location
New Mexico
Vehicle(s)
2019 Jeep JL V6 SportS, (Retired 74 CJ-5, 80 CJ-7)
Occupation
Just ask @cosine he knows!
No, not sarcastic. Genuine concern - I am a worrier - it is a big investment.
Luckily that's one area where no worries are needed. Confirming lug nut torque, oil fill levels, other fluid reservoirs, etc. those are things you should confirm after EVERY service, or just DIY and confirm it as you do it :)
 
OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Threads
29
Messages
885
Reaction score
661
Location
Las Vegas, NV
Vehicle(s)
2024 JL Willys XR V6
Occupation
Network Architect & Engineer
How exactly does the knock sensor and the ECU function - I am aware that the knock sensor basically has a piezoelectric crystal listening at a frequency - that of a ping. Once it detects a vibration at that frequency, it sends a voltage to the ECU which then retards the timing of the spark to prevent detonation.
I am curious to find out if the timing is retarded proportionally to the fuel mixture. In my case as I am graduating from 87 (filled by the dealer) to 91 in incremental fill ups over time, and my fuel mixture is a little over 89, is the timing retarded proportionally or is it retarded to an absolute value regardless?
In other words or a different way to ask the same question is, if I am at 87 octane, would my engine performance be more degraded than if am at 89.5 octane?
 

blnewt

Well-Known Member
First Name
Brad
Joined
Oct 8, 2018
Threads
96
Messages
9,876
Reaction score
23,795
Location
New Mexico
Vehicle(s)
2019 Jeep JL V6 SportS, (Retired 74 CJ-5, 80 CJ-7)
Occupation
Just ask @cosine he knows!
It will retard the timing based on whatever octane it detects, so it will gradually advance the timing as you get closer to full 91 Octane. Probably take about 3 more full tanks of 91 to be at the performance level of true 91 Octane but TBH you won't really notice much difference since it will be over such a prolonged time. I wouldn't lose any sleep over this, if you have a 401k I'd me much more concerned about that.
 

Sponsored

OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Threads
29
Messages
885
Reaction score
661
Location
Las Vegas, NV
Vehicle(s)
2024 JL Willys XR V6
Occupation
Network Architect & Engineer
It will retard the timing based on whatever octane it detects, so it will gradually advance the timing as you get closer to full 91 Octane. Probably take about 3 more full tanks of 91 to be at the performance level of true 91 Octane but TBH you won't really notice much difference since it will be over such a prolonged time. I wouldn't lose any sleep over this, if you have a 401k I'd me much more concerned about that.
Thanks - I learn so much on this forum!
BTW, my IRA is already down 15% since the last few months. :(
Hopefully the first half of 2019 is better on the markets than the second half of 2018.
 

ormandj

Well-Known Member
Joined
Aug 19, 2018
Threads
31
Messages
547
Reaction score
420
Location
San Antonio, TX USA
Vehicle(s)
2024 JLUR X 4xe
Thanks - I learn so much on this forum!
BTW, my IRA is already down 15% since the last few months. :(
Hopefully the first half of 2019 is better on the markets than the second half of 2018.
That's not going to get better anytime soon. Can't help you with that one, the stock market is insane right now - nothing makes sense except to short-term investors trying to capitalize on short-term gains, and that doesn't bode well for the long-term economy. House of cards and all, and we've been propping up a mess with low interest rates for a while now. It eventually has to fall down so it can be re-built. Hopefully this next round on a more stable base of mid/long-term investments (not holding my breath).

You used to invest in companies you believed in and that had long-term visions that aligned with yours, and the market was comprehensible. Now it's computers vs. computers all trying to maximize pennies on short-term trades at insanely high volumes to generate gains, and people capitalizing on this as well. The long-game folks are just collateral damage in the short-term, but will be fine mid/long.
 

ormandj

Well-Known Member
Joined
Aug 19, 2018
Threads
31
Messages
547
Reaction score
420
Location
San Antonio, TX USA
Vehicle(s)
2024 JLUR X 4xe
It will retard the timing based on whatever octane it detects, so it will gradually advance the timing as you get closer to full 91 Octane. Probably take about 3 more full tanks of 91 to be at the performance level of true 91 Octane but TBH you won't really notice much difference since it will be over such a prolonged time. I wouldn't lose any sleep over this, if you have a 401k I'd me much more concerned about that.
To be clear, there is no octane detector; the timing is just advanced (with a hard limit, which is why running higher than 91 won't give even more power) until knock occurs, then backed off slightly. This happens periodically, which is why it takes a little for it to 'learn' the fuel mixture you have. I do agree with the tank suggestion though, just fill up normally the next few times with 91, as you would, and you'll probably be running optimally for the engine.
 

gsxr310

Well-Known Member
Joined
May 21, 2018
Threads
12
Messages
281
Reaction score
499
Location
CA
Vehicle(s)
2018 JLUR
You could use Torco Octane booster. They sell it on Amazon
 

wvgasguy

Well-Known Member
Joined
Oct 3, 2018
Threads
7
Messages
342
Reaction score
313
Location
wv
Vehicle(s)
2019 JLUR / 2017 TRD Pro 4Runner / 2016 Suburban LTZ and 1979 Chevy K10 short bed
Occupation
Retired
I'm on my first tank and really don't know what the octane the dealer used. It is what it is, but I'll wait until I'm almost empty before filling up with higher octane. Milage right now sucks, but it's only at 150 so I'll let it have a few break-in miles on whatever gas is in it before I worry about my mileage. Unless you are almost empty topping off with 91 octane every so often will take several tank fulls before you actually have a full tank of 91
 

Sponsored

OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Threads
29
Messages
885
Reaction score
661
Location
Las Vegas, NV
Vehicle(s)
2024 JL Willys XR V6
Occupation
Network Architect & Engineer
I'm on my first tank and really don't know what the octane the dealer used. It is what it is, but I'll wait until I'm almost empty before filling up with higher octane. Milage right now sucks, but it's only at 150 so I'll let it have a few break-in miles on whatever gas is in it before I worry about my mileage. Unless you are almost empty topping off with 91 octane every so often will take several tank fulls before you actually have a full tank of 91
My gas tank should be around 90.5 octane - I am filling 91 when it gets to half.
I have done 800 miles so far - averaging 21.5 mpg.
 
OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Threads
29
Messages
885
Reaction score
661
Location
Las Vegas, NV
Vehicle(s)
2024 JL Willys XR V6
Occupation
Network Architect & Engineer
You could use Torco Octane booster. They sell it on Amazon
I read that Torco will put an orange residue on the spark plugs.
 

Karl_in_Chicago

Well-Known Member
First Name
Karl
Joined
Nov 4, 2017
Threads
14
Messages
827
Reaction score
810
Location
Chicago
Vehicle(s)
Acura RL, Chevrolet Corvette, Harley-Davidson FLHTC Electra-Glide Classic
I guess if you really wanted to get rid of it that bad you could have just gone to a diner, stuck a siphon hose in your tank, and taped a sign to the Jeep saying "FREE GAS HERE - HELP YOURSELF!". Go inside and have a breakfast or coffee and come out and drive straight to the nearest gas station and filled up with 91.
 

LincolnSixAlpha

Well-Known Member
First Name
Brian
Joined
Oct 26, 2018
Threads
15
Messages
350
Reaction score
277
Location
Arizona
Vehicle(s)
2018 Jeep Wrangler Unlimited Rubicon
Vehicle Showcase
1
I happen to have a Rebel Gas Station just a mile down the street from my home. They have 100 Octane Oxygenated Unleaded fuel. I am wondering if "Oxygenated" may mean too much Ethanol maybe? If I fill a couple of gallons of 100, I will reach 91 immediately. But is there any risk?
Or is there more risk in driving with 87 with some carbon deposits while I reach 91?
I think you may be overthinking the situation. To the other's points, I'd just use the 87, then refill with 91 when your tank is empty. On a related note, my daughter's 2004 Volvo XC90 requires 91, however, we've been putting 85 in it for years. It's a 2.5L 5 Cylinder Turbo motor. Runs fine on the lowest grade. Also, my previous BMW's required premium. Of course, I liked to put premium in, but again, but have put in lesser grades. Also ran fine. My 2 cents.
 
OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Threads
29
Messages
885
Reaction score
661
Location
Las Vegas, NV
Vehicle(s)
2024 JL Willys XR V6
Occupation
Network Architect & Engineer
I guess if you really wanted to get rid of it that bad you could have just gone to a diner, stuck a siphon hose in your tank, and taped a sign to the Jeep saying "FREE GAS HERE - HELP YOURSELF!". Go inside and have a breakfast or coffee and come out and drive straight to the nearest gas station and filled up with 91.
Believe me, I though of siphoning the 87 out. :D
Sponsored

 
 



Top