question about octane rating - Nissan Forum
B14 95-99 chassis 1995-1999 Sentra and 1995-1998 200SX

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 21 Old Aug 26th, 2002, 03:17 PM Thread Starter
I think I lost my mod-nes
 
97sentragxe's Avatar
 
Join Date: Jun 2002
Location: Ohio
Posts: 313
question about octane rating

Since theres been so much talk lately about gasolines, mothballs, etc. I myself have a question:
At a Sunoco station near my house, I noticed that they have gas with an 86 octane rating. It's significantly cheaper than regular 87 octane (10 cents per gallon) and with it being only one point lower than 87, I just wonder if this could be used in my fuel system with no negative side effects. So far, I've used only 87 octane every time I've gotten gas, except one time when the 87 octane pump was broken, I put some 89 octane in. (My car was TONS faster, too with that better gas. ) Anyway, I assume this 86 octane would be okay for a Sentra, since a car cannot be much more of an econobox that a Sentra, but since I'm near a lake, could this stuff be meant more for things like boats, jetskis, and starting campfires?
Thanks for help.

My Sentra
I miss that car.
97sentragxe is offline  
Sponsored Links
Advertisement
 
post #2 of 21 Old Aug 26th, 2002, 03:59 PM
Nissan Fanatic
 
ccroaddog's Avatar
 
Join Date: Jun 2002
Location: Federal Way
Posts: 479
if your car is a lot faster with 89 octane dont you think it may be a little slower with 86 octane? Besides im pretty sure that your vehicle requires 87 octane and shouldnt go any lower. Just spend the extra 10 cents

looking
post #3 of 21 Old Aug 26th, 2002, 04:06 PM
bitter old man
 
bahearn's Avatar
 
Join Date: Jul 2002
Location: La Porte, Texas
Posts: 1,456
If your car was really "tons" faster, then your timing is being retarded when using 87-octane. If 89-octane really was faster, you'd notice an improvement in gas mileage, too. So, if 87-octane requires the ECU to retard timing, 86-octane would require even more timing retard. Less power, lower mileage. If the lower grade is 7% less cost, you need to get at least 7% better gas mileage with the higher grade to make the economics work for using 87-octane. Of course, if your SOTP dyno can't stand the power loss, who cares about economics.

Bruce in Houston
'94 Nissan Sentra SE-R w/ $tuff, converting to ITA
'98 Suzuki Bandit 1200S w/ $tuff
'02 Dodge Dakota SLT 4-dr tow beast, stock!
post #4 of 21 Old Aug 26th, 2002, 04:37 PM Thread Starter
I think I lost my mod-nes
 
97sentragxe's Avatar
 
Join Date: Jun 2002
Location: Ohio
Posts: 313
I figured the would be obvious enough, but I guess not. No, my car was NOT faster at all when I used the 89 octane gas, I said that to make fun of those people who think that putting "better" gas in their car will make them a lot faster.

My Sentra
I miss that car.
97sentragxe is offline  
post #5 of 21 Old Aug 26th, 2002, 04:48 PM
Nissan Enthusiast
 
Join Date: May 2002
Location: Jackson, NJ
Posts: 70
Actually, in SCC October 2002 issue the '03 Nissan 350Z made an additional 5 hp and 2 lb-ft of torque at the wheels on the dyno when going from 91 octane to 100 octane.
post #6 of 21 Old Aug 26th, 2002, 05:54 PM
Post Freak
 
Join Date: Apr 2002
Posts: 1,075
Quote:
Originally posted by vrux
Actually, in SCC October 2002 issue the '03 Nissan 350Z made an additional 5 hp and 2 lb-ft of torque at the wheels on the dyno when going from 91 octane to 100 octane.
Well, the 350Z was designed for premium fuel.

*edit* Right, because of knock(see my post) - Pat

Last edited by PatScottAKA99XE; Aug 26th, 2002 at 09:05 PM.
post #7 of 21 Old Aug 26th, 2002, 09:02 PM
ex-Super *********
 
PatScottAKA99XE's Avatar
 
Join Date: Apr 2002
Location: VT
Posts: 1,410
Send a message via AIM to PatScottAKA99XE Send a message via Yahoo to PatScottAKA99XE
Octane rating: The fuels ability to resist knock( ping)
The higer the ratting the more knock resistant it is. Just about every owners manual I have seen give a minimum suggested octane. Dont go below it.

FYI, the higher the octane, the slower it burns.

If your car is designed for 87, putting in a higer octane will not make it faster. It only works if you have mods that tend to increase the chance of knock.

Patrick Scott
Yeah, thats a roll cage in there.
I shall call him...Mini-Me
PatScottAKA99XE is offline  
post #8 of 21 Old Aug 27th, 2002, 12:48 AM
KdudL
Guest
 
Posts: n/a
higher octane fuel means less knocking!! if higher octane fuel id 10cents more go for it. better in the long run
post #9 of 21 Old Aug 27th, 2002, 08:45 AM
Post Freak
 
Join Date: Apr 2002
Posts: 1,075
Quote:
Originally posted by KdudL
higher octane fuel means less knocking!! if higher octane fuel id 10cents more go for it. better in the long run
Higher octane fuel is only better if it's required for your car. Unless you're running timing more advanced than the factory specs for 87 octane fuel, turbo, or nitrous you're just wasting the 10 cents per gallon.
post #10 of 21 Old Aug 27th, 2002, 08:59 AM
Nissan Fanatic
 
Join Date: Jul 2002
Posts: 413
Quote:
Originally posted by 97sentragxe
I said that to make fun of those people who think that putting "better" gas in their car will make them a lot faster.
As everyone is stating, higher octane in some cases will increase the performance of your car, but too high of an octane could be a waste of money. This is esepcially true, as everyone has stated, when you advance your timing.

Don't go below recommended fuel specs. Those are the most conservative specs for fule rating.

Brandon
'96 G20 (modified)
post #11 of 21 Old Aug 27th, 2002, 12:20 PM
bitter old man
 
bahearn's Avatar
 
Join Date: Jul 2002
Location: La Porte, Texas
Posts: 1,456
Quote:
FYI, the higher the octane, the slower it burns.
Technically, that's not true, but it will suffice for the discussion at hand.

Bruce in Houston
'94 Nissan Sentra SE-R w/ $tuff, converting to ITA
'98 Suzuki Bandit 1200S w/ $tuff
'02 Dodge Dakota SLT 4-dr tow beast, stock!
post #12 of 21 Old Aug 27th, 2002, 02:07 PM Thread Starter
I think I lost my mod-nes
 
97sentragxe's Avatar
 
Join Date: Jun 2002
Location: Ohio
Posts: 313
Hmm.. Maybe 89 octane would be fine, then. Kind of a mix between "bare minimum" and "ridiculous excess"

My Sentra
I miss that car.
97sentragxe is offline  
post #13 of 21 Old Aug 27th, 2002, 02:19 PM
96BlkSE-R
Guest
 
Posts: n/a
I run nothing but 93 octane in my 96 SE-R. Wasting money - no. With the mods I have, timing I've bumped up, etc. the car runs like a brick when I put even 89 in it.

Plus, I have had fewer EGR problems that some of my other SR20 friends. But, that could just be luck. Or maybe not...
post #14 of 21 Old Aug 27th, 2002, 04:21 PM
Nissan Enthusiast
 
Join Date: Jul 2002
Location: Atlanta
Posts: 205
It also tends to be better for the engine to run higher octane if you live in extreme heat areas, (avg 100+ degrees F) as the external heat obviously makes the car run hotter which in turn tends to make the car more susceptable to knock...likewise, if you drive in high temp areas in a lot of stop and go (you'll most likely tend to have the a/c on in this situation too which makes it even worse), higher octane will tend to benefit as well, you may not see gas mileage increases but you will help lengthen the life of your car's engine. This actually holds true for just about any car despite what the manual says. Octane tends to follow your driving tendancies and needs and is more importantly based on additional heat generating components/mods like everyone else has mentioned.
97PocketRocket is offline  
post #15 of 21 Old Aug 27th, 2002, 04:44 PM
bitter old man
 
bahearn's Avatar
 
Join Date: Jul 2002
Location: La Porte, Texas
Posts: 1,456
Any heat input into an engine ups its octane requirement, whether it be intake air, fuel, coolant, etc. I don't know the magnitude increase in octane requirement for a given input; time to retrieve my copy of "Internal Combustion Engines in Theory and Practice, Vol 2.".

Bruce in Houston
'94 Nissan Sentra SE-R w/ $tuff, converting to ITA
'98 Suzuki Bandit 1200S w/ $tuff
'02 Dodge Dakota SLT 4-dr tow beast, stock!
Reply

  Nissan Forum > Sentra, Pulsar, NX, B14 200SX > B14 95-99 chassis

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Nissan Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



  Similar Threads
Thread Thread Starter Forum Replies Last Post
newbie. vq35de octane question. please help. 01pathySE Truck & SUV 6 Mar 6th, 2004 10:20 AM
Does hjgher octane gas cause more carbon build up? dschrier General Discussion 11 Jul 30th, 2003 09:55 AM
fuel question... Sentra4Me B14 95-99 chassis 20 Jul 11th, 2003 09:33 AM
Pump octane #'s and Octane Boost Silvspec86 B15 2000-2006 30 May 14th, 2003 07:24 AM
high octane fuel in europe janko B14 95-99 chassis 1 Jan 9th, 2003 12:11 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On