[Judas]

Staff Note: the first 6 posts of this thread were moved from the AMD quad core platform thread because it went way too off topic. Please continue the discussion here



You can run normal unleaded in a sports car.... why do people insist that you shouldn't?

The north american sporty cars use identical engines to that of there eco's and larger cars that use unleaded. All the higher octane does is slightly increase power while/by reducing the cars "ping", which can be done to any vehicle identically. Course the more sportier ones say only premium but your not going to hurt anything running normal unleaded.

I was under the impression that With Windows XP Home and SP2, if a physical single cpu was recognized as having more then 2 cores onit, that home would allow 4 seperate threads to be active. (some intel quad core was presenting this info i think).

[Dark Lord]

im spark knocking like all hell in my vette right now and im running 92 octane. the timeing is either god awful, or the gas station isnt actually selling 92 anymore.

my bet is a little bit of column A, and a little of coulmn B. gotta go dig out the damn timeing light some time this week. god only knows where that is.

[Judas]

The vette has a standard engine block size/design, it just happens to be tuned and powered up a fair bit more then your standard stock setup.

Using a higher octane is saposed to increase the speed of the "kablamm" but decrease the heat created by it due to the speed of it. (confuzzled)


reguardless, the Dual core cpu's work on home, Quad core is "saposed" to work on home. Pro should be more widely useable.

[CDsDontBurn]

Originally Posted by Judas

Using a higher octane is saposed to increase the speed of the "kablamm" but decrease the heat created by it due to the speed of it. (confuzzled)

actually.....higher octane burns hotter. hotter burn means two things:

1. hotter explosion means more powerful explosion, more powerful explosion, means overall more power, a.k.a. horse power.
2. a hotter explosion burns more residue/deposits leaving behind less deposits, which in turn means a cleaner engine.

now, not all engines are tuned to burn high octane fuel. economy cars are intentionally designed to run best on regular octane levels. sports cars, like DL's vette, are designed to run best premium octane.

[amdking]

Originally Posted by CDsDontBurn

actually.....higher octane burns hotter. hotter burn means two things:

1. hotter explosion means more powerful explosion, more powerful explosion, means overall more power, a.k.a. horse power.
2. a hotter explosion burns more residue/deposits leaving behind less deposits, which in turn means a cleaner engine.

now, not all engines are tuned to burn high octane fuel. economy cars are intentionally designed to run best on regular octane levels. sports cars, like DL's vette, are designed to run best premium octane.

um....there is no temperature difference between octanes. Its simply that higher octane burns SLOWER. You need a slower burning fuel when you are running aggressive engine timings or boost. Thats simply why sports cars or high end cars require higher octane fuel. Because when it burns slower you avoid pinging or detonation. It has nothing to do with temperature. In truth it also does not make your engine cleaner either. Also, if you have to use higher octane fuel in a car thats not spec'd, and is stock, to take it to keep the car running smooth(this isnt too uncommon) this means there is something drastically wrong with your car. Also, you lose power when running higher octane in a car thats meant to run with lower octane.

An easy and good way to keep your engine clean is redline or get close to it here and there, under load of course. Because, that will heat up everything enough drastically burn away those carbon deposits that exist in the engine.

[dj_stick]

the reason why the higher octane burns slower, is because it's actually not octane (not a straight chain hydrocarbon)
the molecules will still have the same molecular formula (C8H18) but a different structural formula, with less reaction points, so it burns slower and is more stable, also the faster it burns, the more heat is actually produced…


and this thread is DEFINATELY off topic

EDIT: i've split the thread in the news forum so that thread stays on topic - continue to talk about petrol/octane count here

[TheBlackCat]

Originally Posted by dj_stick

the reason why the higher octane burns slower, is because it's actually not octane (not a straight chain hydrocarbon)

Octane does not need to be straight-chain. Isooctane, which is what you are talking about, is still considered octane.

Originally Posted by dj_stick

so it burns slower and is more stable, also the faster it burns, the more heat is actually produced…

The total energy produced is based on the bonds present in the molecule. Isooctane has the same number of the same type of bonds as regular octane, so the total energy released is the same. The amount of energy usable by the engine, however, does depend on reaction rate.

[SFOSOK]

Cheaper fuel gunks up ur engine, it doesn't run as smooth, and can lead to problems in the future. If you have something like an old truck or something it doesn't matter, but a high performance V8? That junk is likely to ruin it.

[dj_stick]

Originally Posted by TheBlackCat

Octane does not need to be straight-chain. Isooctane, which is what you are talking about, is still considered octane.

i was referring to the branched chain molecules (higher % of branched chains = higher octane rating)
2,2 di-ethyl butane will burn slower than octane based on it's physical structure

Originally Posted by TheBlackCat

The total energy produced is based on the bonds present in the molecule. Isooctane has the same number of the same type of bonds as regular octane, so the total energy released is the same. The amount of energy usable by the engine, however, does depend on reaction rate.

energy produced is the same, but with higher octane fuels, it's over a longer period, so the energy/heat buildup is not as intense

[Matth]

My understanding is that higher octane is required in order to allow for higher compression without pre-ignition. Or that the ignition of lower octane fuels at higher compression causes too abrupt a detonation. Running an engine on lower octane than it was designed for, normally requires the timing to be retarded slightly.

Normal timing tends to be a few degrees BEFORE top dead centre do that the ignition of the fuel takes hold at some point beyond TDC. Higher compression causes faster combustion, while higher octane fuel actually has SLOWER combustion - the balance being that higher compression increases the power output

Example
http://www.miata.net/garage/KnowYourCar/S10_Timing.html

[Lelisevis]

92 octane . Wow im running the Teg on 99. I can definitely tell the difference between standard 95 and the 99 in this car. Risks of running a car with too high rated fuel are pre-detonation which results in smoky, noisy, fiery death

[The_Neon_Cowboy]

besides the octane factor premium fuel often also include additives to clean and maintain

[TheBlackCat]

Originally Posted by Lelisevis

92 octane . Wow im running the Teg on 99. I can definitely tell the difference between standard 95 and the 99 in this car. Risks of running a car with too high rated fuel are pre-detonation which results in smoky, noisy, fiery death

I think you have it backwards. High octane reduces the risk of pre-detonation (knocking).

[Dark Lord]

advantage to liveing over in the UK, you guys have much higher octane level then us.

99 octane is on the verge of race level gas here (drag strip type stuff, not all out nascar/F1) i think the race gas out here is 107 and costs about 6 bucks a gallon.

regular here is 87, midgrade is 89, and premium is 92/93 depending on where you go.

i know octane levels have gone down over the years here compared to what they used to be. the old L88 corvettes (427CI 435HP Tri-power carbs) have a HUGE warning sticker on the console that says NO LOWER THEN 104 OCTANE GAS TO BE USED. that used to be a pretty common level back in the day, seeing as his car was still a regular street legal car. was just track ready at a moments notice.

[CDsDontBurn]

Originally Posted by Dark Lord

regular here is 87, midgrade is 89, and premium is 92/93 depending on where you go.

to add to that, here in california it's lower. premium is rated at 91 here. a few years ago it was rated at 92, but they changed that and brought it down to 91.

[Kombatant]

Lowest you can find here in Greece is 95, with premium being 100+

[CDsDontBurn]

how much is gas going for in europe? i know it's something ridiculous compared to here in the states.

now, how much is gas going for in other parts of the states? here in california, we're paying ~$2.53/gal for 87 octane.

[Kombatant]

Ok, here's a try: 82 eurocents per litre. Convert that

[niceguyrichy]

we were up to £1 a litre a month or so back .
dropped back by about 5p, so now its $1.77us a litre.
dunno how many's in a gallon, you do the math

[CDsDontBurn]

1gal. = 3.7825L

so if i were paying what you're paying richy, i'd be about $6.70/gal

and if i were paing what kombatant is paying, it'd be $1.03/L which is $3.89/gal, which is about 20 cents higher than what we were paying here during summer

[niceguyrichy]

yar , it's pricey

bloody road tax is up too, I just paid £175 for a years tax on a god-damn hatchback

[CDsDontBurn]

lol...taxes here are crazy. but i guess you guys are taxed like no other, so i shouldn't be complaining .

[Kombatant]

Bear in mind though that a) traditionally here in Europe we pay MUCH more for fuel (so think back how much we laughed while you americans whined about high fuel prices a few months back ) b) I pay that price for 95 octane benzin, and from what i understand you guys consider that to be premium, so it's best to compare with that.

[Tinkerhell]

Well, with my kroger discount card, after spending $100 for groceries, I get regular for $1.83 a gallon.

I don't complain about gas prices too much. My area is one of the cheapest in the states as a general rule. I got a truck and an old eagle talon tsi so I just buy the cheapest gas I can find. I'll leave all the high test stuff to you race guys. I've not bought anything else since I was in my teens and had a bike. I would put some top end race fuel in that about once every month to get everything nice and clean. It made a heck of a difference though.

[Dark Lord]

im paying about 2.07 for regular right now.

[H3X4D3C1M4L]

To me its like this: If you love your car you'll put premium fuel in it.

Same way if you love your water cooling you'll put good water in it and not urine.


Now diesel that's where its at.

[Judas]

Diesel has various forms of it's high compression power...

Actually water cooling is better when it's filled with impurities as it draws on more heat then without, similare to that of how if you put antifreeze in a car, to much can actually keep the engine warmer if not to hot and gel when it gets freezeing cold. To little results in the water boiling though, or freezeing lol.

[CDsDontBurn]

Originally Posted by H3X4D3C1M4L

To me its like this: If you love your car you'll put premium fuel in it.

Same way if you love your water cooling you'll put good water in it and not urine.


Now diesel that's where its at.

what if you have one of those hybrid cars/trucks that run best on regular octane and you love the car? should you still put premium in it?

and diesel is more expensive than regular octane......at least that's the case in my area.

[Matth]

In general, it should run best on the octane rating that it was designed/tuned for.

As for fuel brand, some say there's no difference, but others claim the big name brands do perform better.

Mind you, others claim that some "magic beans" in the tank will improve power, economy, clean the engine and create world peace (ok, I made the last one up!).

PS. I admit some bias (on additives), as I used Slick 50 (oil additive) and it worked for me, with a reputable motor store own brand oil of the correct rating for the working conditions (10W40, not 20W50) - maybe more expensive oil would have done the same.

[H3X4D3C1M4L]

Originally Posted by CDsDontBurn

what if you have one of those hybrid cars/trucks that run best on regular octane and you love the car? should you still put premium in it?

and diesel is more expensive than regular octane......at least that's the case in my area.

Diesel is consistantly 5 cents cheaper/litre here where I get gas anyway.

As for the hybrid car thing... those don't count. Why? 'cause I said so.