Recent Topics
High Mileage Oil Advice ?
by ChrisD46
32 minutes 28 seconds ago
Car that runs on saltwater
by hate2work
44 minutes 43 seconds ago
AAP code, good for today only...
by mjk
59 minutes 58 seconds ago
F1 - 2014 Italian Grand Prix
by gofast182
Today at 07:48 AM
1998 Olds 88-3800 engine
by ET16
Today at 06:20 AM
ATF Change (4T65E-HD) - What to do?
by tony1679
Today at 05:16 AM
Popular Science article in 1976 on synthetic oils
by Apollo14
Today at 03:05 AM
9/1-10/5 Pep Boys Sales Ad
by tenderloin
Today at 02:21 AM
To Buy the Jug, or use another weight?
by Timo325
Today at 02:00 AM
8/31-9/7 Pep Boys Sales Ad
by tenderloin
Today at 01:57 AM
weedeater one we261
by turbodieselfreak
Today at 01:42 AM
Engine rebuild durability?
by PandaBear
Today at 01:31 AM
Newest Members
DennisWaller, DMackey, Mambo_Dave, 2165, JohnSawyer
51160 Registered Users
Who's Online
82 registered (1foxracing, 65f100, andyd, 05LGTLtd, Astro14, abycat, 8 invisible), 1457 Guests and 404 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
51160 Members
64 Forums
218613 Topics
3447129 Posts

Max Online: 2862 @ 07/07/14 03:10 PM
Donate to BITOG

Page 1 of 4 1 2 3 4 >
Topic Options
#1825247 - 03/21/10 01:00 AM Does premium unleaded burn hotter than regular
RTBandit Offline


Registered: 02/24/09
Posts: 75
Loc: California
Just curious - Does 91 octane gas create a hotter explosion than 87 octane? All input is appreciated.

Top
#1825254 - 03/21/10 01:04 AM Re: Does premium unleaded burn hotter than regular [Re: RTBandit]
daves66nova Offline


Registered: 04/11/04
Posts: 3103
Loc: los angeles
The numbers are just ratings for the level of resistance to detonation,it is not an indicator of "performance"
_________________________
THIS SPACE FOR RENT, PLEASE PM ME.

Top
#1825260 - 03/21/10 01:14 AM Re: Does premium unleaded burn hotter than regular [Re: daves66nova]
Colt45ws Offline


Registered: 08/15/06
Posts: 7382
Loc: Central Washington
Originally Posted By: daves66nova
The numbers are just ratings for the level of resistance to detonation,it is not an indicator of "performance"

Quoted for truth. Octane is associated with performance because high performance engines have designs that require higher octane. Turbocharging, supercharging, high compression are all reasons that an engine has more performance, they are also reasons they need high octane so they don't have pre-ignition. Pre-ignition can rattle an engine apart and/or burn holes in places they shouldnt be.


Edited by Onmo'Eegusee (03/21/10 01:14 AM)
_________________________
-Colton
2004 Ford Crown Vic LX, 81k "Tank"
2002 Ford Crown Vic PI, 162k "Highwayman" (Ex-Kootenai County, ID Unit #42)

Top
#1825266 - 03/21/10 01:23 AM Re: Does premium unleaded burn hotter than regular [Re: Colt45ws]
RTBandit Offline


Registered: 02/24/09
Posts: 75
Loc: California
My question is about temperature not performance.

Top
#1825268 - 03/21/10 01:33 AM Re: Does premium unleaded burn hotter than regular [Re: RTBandit]
expat Offline


Registered: 05/12/09
Posts: 3795
Loc: Canada
By and large,NO.
ANY substance added to the gas that helps prevent, or delays preignition with give the Gasoline a higher octane rating.
For may years a type of Lead compound was used, Methanol and Ethanol will also serve to raise the octane rating. But they will not cause the fuel to burn hotter.

Top
#1825270 - 03/21/10 01:34 AM Re: Does premium unleaded burn hotter than regular [Re: RTBandit]
Shannow Offline


Registered: 12/12/02
Posts: 26336
Loc: a prison island
Nope, not hotter, faster, slower, or any of the things that our local mower repair man keeps telling my co-workers.

It is merely more resistant to self igniting in the presence of pressure, temperature, and hot spots.

It used to (often) have a lower energy content, but modern refining has made high density high octane fuels.
_________________________
2003 Nissan Navara ZD30 TD, 4L Penrite racing 5W30, 3L M1 5W50
1997 Statesman Caprice, L67 (10psi), Castrol Magnatec 5W30.
Briggs Quantum, Penrite 20W60


Top
#1825272 - 03/21/10 01:35 AM Re: Does premium unleaded burn hotter than regular [Re: RTBandit]
expat Offline


Registered: 05/12/09
Posts: 3795
Loc: Canada
Originally Posted By: RTBandit
Just curious - Does 91 octane gas create a hotter explosion than 87 octane? All input is appreciated.


It's not an explosion, it's a burn.
Or it should be!

Top
#1825273 - 03/21/10 01:36 AM Re: Does premium unleaded burn hotter than regular [Re: RTBandit]
Trajan Offline


Registered: 07/16/05
Posts: 3314
Loc: SE PA
Octane rating does not relate to the energy content of the fuel. It doesn't burn any hotter.
_________________________

Lack of harm does not mean proof of benefit.

Top
#1825331 - 03/21/10 06:27 AM Re: Does premium unleaded burn hotter than regular [Re: Trajan]
Boomer Offline


Registered: 09/19/08
Posts: 1638
Loc: Pennsylvania
Some cars had warnings years ago on running high octane fuels as they were set to use regular. The reason given was burning exhaust valves. This was not due to higher temps but to a slightly longer burn time that produced a hotter exhaust gas that caused the exhaust valve to run hotter. My wife's Saturn has a warning like this in the owner's manual and I think Buick may have had it as well.
_________________________
2003 Saturn L 300 116,500 miles
2013 VW Passat TDI SE, 16,100miles
2014 VW Jetta TDI SportWagen 2850 miles

Top
#1825352 - 03/21/10 07:04 AM Re: Does premium unleaded burn hotter than regular [Re: Boomer]
Bluestream Offline


Registered: 09/13/03
Posts: 3893
Loc: Waterloo, ON
It burns slower, so my guess is it would be cooler
_________________________
2000 Cavalier 2.2 A4
2000 VW Beetle 1.8T M5
2000 Ford Explorer 4.0 4X4
1991 BMW 735iL
"A fool and his money are soon parted" - Thomas Tusser

Top
#1825375 - 03/21/10 07:48 AM Re: Does premium unleaded burn hotter than regular [Re: Bluestream]
ARCOgraphite Offline


Registered: 05/17/09
Posts: 8438
Loc: N.H, U.S.A.
Is this on a bet? Having a Molotov Cocktail? If you want more energy out of a cylinder burn you have to add MORE fuel and MORE air. Or Nitrous (air) and more fuel. Not enough air will make the burn too hot.
_________________________
2014 Nissan Note S 5MT, OC#0 170mi-FACTORY 5W30+Nissan China Filter
2014 Forester 6MT 5Door, OC#0 540mi-FACTORY 0W20(?)+TokyoRoki 160 Filter

Top
#1825381 - 03/21/10 08:00 AM Re: Does premium unleaded burn hotter than regular [Re: RTBandit]
zulu Offline


Registered: 01/21/08
Posts: 528
Loc: Kansas
Not hotter, just slower.
_________________________
09 Silverado 5.3 -> M1 5W-30/AC Delco PF48
12 Civic Si 2.4 -> Honda (CP Blend) 0W-20/Honda A02

Top
#1825383 - 03/21/10 08:02 AM Re: Does premium unleaded burn hotter than regular [Re: ARCOgraphite]
cjhepburn Offline


Registered: 02/24/09
Posts: 251
Loc: Boston
I don't know if it burns hotter but it burns slower. That's why you need to adjust the timing on older cars to not ping on lower octane fuels.
_________________________
'08 Civic LX, M1 EP 5w-20, 10000 OCI - 98k.
'03 Forester XRS, GC 0w-30, 5000 OCI - 78k

Top
#1825384 - 03/21/10 08:03 AM Re: Does premium unleaded burn hotter than regular [Re: Bluestream]
Jax_RX8 Offline


Registered: 12/13/06
Posts: 345
Loc: Northern VA, USA
Originally Posted By: Bluestream
It burns slower, so my guess is it would be cooler


This is a mistake many people think - just because it is less prone to pre-ignite, through additives, does NOT mean it burns slower.

Once ignited, Premium burns at basically the same rate as Regular.


Edited by Jax_RX8 (03/21/10 08:04 AM)

Top
#1825405 - 03/21/10 08:40 AM Re: Does premium unleaded burn hotter than regular [Re: Jax_RX8]
mikered30 Offline


Registered: 09/10/05
Posts: 1286
Loc: PA
So running 93 octane in an engine that calls for 87 will not lead to increased carbon build up compared to running 87 all the time?

Top
Page 1 of 4 1 2 3 4 >