TRAC3 Posted February 20, 2007 Posted February 20, 2007 no pinging, no running issues, and he's mechanical type of guy, knows about cars, trucks, tractors, etc... he did try to convince me that I should put in a tank of 87 to see if it really made a difference..... I started to explain that it wouldn't be so good for my stg2+ with TDC 93 octane software... but I just let it go anyone else here run less than 93/94 octane in their cars?
krzyss Posted February 20, 2007 Posted February 20, 2007 What is the milage he gets and how often he revs it past 3k rpm? Krzys
SQC049 Posted February 20, 2007 Posted February 20, 2007 No. Your friend is a moron. Stick to high test. Super JDM part out: http://legacygt.com/forums/showthread.php?t=65039 PM me an offer!
TRAC3 Posted February 20, 2007 Author Posted February 20, 2007 well it's his wife driving the car, but she revs over 3 k pretty regularly when she steps on it, mileage is better than mine.. I think around 23-24 average, and that's mixed bag of commuting local roads short highway stretches I know to stick to high test, I just found it funny that they were experiencing no issues whatsoever. whenever noobs to the B5 audi A4's put in low test, they always had pinging, detonation, increased turbo lag and whatnot...
wukindada Posted February 20, 2007 Posted February 20, 2007 He should have just purchased a 2.5i..... It's kinda like the guy I saw pumping 87 oct in his brand new 07 Vette this past saturday. Sure it can be done, but why buy a performance car? Toyota 6EATS .........SUCK!!!!!!
SWP-LegacyGT Posted February 20, 2007 Posted February 20, 2007 buying a $25k-$30k car and putting cheap gas it. god, might as well bought a kia.
wukindada Posted February 20, 2007 Posted February 20, 2007 Easy now......... I drive a Daewoo wagon & I run premium;) Toyota 6EATS .........SUCK!!!!!!
Prime Power Posted February 20, 2007 Posted February 20, 2007 You run what it calls for. The octane rating is not a rating of "power" but of how hard it can be compressed. Run what it calls for. If you run 91 in an 87 you stand to have problems and vice versa. My friend had his ford fuel injectors replaced at 45k because he ran premium. They new right of the bat, first question they asked "did you run premium" he proudly said yes. They said, well theres your problem.
SWP-LegacyGT Posted February 20, 2007 Posted February 20, 2007 Easy now......... I drive a Daewoo wagon & I run premium;) Well my other car is an '01 LL Bean Outback H6 and I run 89 in it because that's all it needs. Point being is given the characteristics of a Turbo charged car, one would think that they wouldn't buy crap gas for a high performance engine. But what do I know, if the guy hasn't had issues up till now, great, but I will put money on engine/fuel injector issues on car owner 2/3/4 of his car if he sells it; or even if he doesn't, I bet their will be some engine issues.
wukindada Posted February 20, 2007 Posted February 20, 2007 Agreed....... Toyota 6EATS .........SUCK!!!!!!
VTsullyman Posted February 20, 2007 Posted February 20, 2007 I bet that ECU has that cars timing retarded big time. 2007 DGM LGT 2003 Suzuki SV650S
Underdog Posted February 20, 2007 Posted February 20, 2007 VT beat me to it. Tell him to check his logs (lol) cause he must be running tons of knock correction unless he drives it without ever getting into boost. The Crimson Dynamo
suba_rus Posted February 20, 2007 Posted February 20, 2007 I use 89 from day one. Now 1.5 years in to it and 20,000 miles- no problems so far. Could be the fact that modern engines run buy a computer chips that can adjust themselves. This is my personal experience, please do not take it as advise or desire to start an argument.
rjundi Posted February 20, 2007 Posted February 20, 2007 The engine management is compensating and producing less HP. However there is an excess of it at stock so it may not bother the owner. It really would be an interesting test if they keep it long term and if any issues if ever arise. The fuel injector issues is pure bunk. I have owned a few cars into 200k range on regular fuel with one recommending premium and not a single fuel problem with them. My parents have owned into the 300k range and nay an issue on no name - brand name fuel with fuel system.
SWP-LegacyGT Posted February 20, 2007 Posted February 20, 2007 The engine management is compensating and producing less HP. However there is an excess of it at stock so it may not bother the owner. It really would be an interesting test if they keep it long term and if any issues if ever arise. The fuel injector issues is pure bunk. I have owned a few cars into 200k range on regular fuel with one recommending premium and not a single fuel problem with them. My parents have owned into the 300k range and nay an issue on no name - brand name fuel with fuel system. As VT stated above.... the ECU is probably retarding the timings to below 250HP on the car and running 87 over time on a TURBO CHARGED CAR will most likely run into fuel injector issues. I'm not argueing over a N/A engine but anyone who runs 87 on a Turbo/Supercharged/Inline6(M3) is going to run into problems eventually. Let's put things into perspective. If you bought a Porsche GT3, would you put 87 in it? Hell, lets say you bought a Ferrari, you going to put Arco 87 octane in it? Morale of the story is a few pennies saved now is a few thousand pennies spent later.
krzyss Posted February 20, 2007 Posted February 20, 2007 I bet that ECU has that cars timing retarded big time. Not to mention boost pressure. Krzys
edmundu Posted February 20, 2007 Posted February 20, 2007 Actually, 87 on a stock car wouldn't be so terrible:icon_surp. The stock tune runs extremely rich, and therefore with lower octane fuel, it is kinda like leaning the fueling out a bit. I mean techinically it isn't(More like raising the combustion temps), but it is pretty much the exact opposite of running racegas on a pump gas map. It isn't going to help, but actually hurt! Now, on any of the various Stg1/2 tunes, they pretty much have taken some fuel out, added boost, and also timing. So I wouldn't run 87 on any AP/Ecutek/Utec/OpenEcu without at least datalogging it a few times to ensure that you aren't upsetting the ECU. And to be really certain, I would flog it, then let it heatsoak, and try it again. Because under ideal cool/winter conditions, it might work great but in summer heat it could be trouble. Ultimately, 87 cannot compare to 93, if tuned for it. The engineer's knew full well that many will attempt/run 87, and have appropriately prepped the Ecu for it.
VTsullyman Posted February 20, 2007 Posted February 20, 2007 As VT stated above.... the ECU is probably retarding the timings to below 250HP on the car and running 87 over time on a TURBO CHARGED CAR will most likely run into fuel injector issues. I'm not argueing over a N/A engine but anyone who runs 87 on a Turbo/Supercharged/Inline6(M3) is going to run into problems eventually. Let's put things into perspective. If you bought a Porsche GT3, would you put 87 in it? Hell, lets say you bought a Ferrari, you going to put Arco 87 octane in it? Morale of the story is a few pennies saved now is a few thousand pennies spent later. +1000000! 2007 DGM LGT 2003 Suzuki SV650S
Tocsin Posted February 20, 2007 Posted February 20, 2007 I didn't notice any change really from 93 to 91. In Cali we don't have anything higher than 91. I miss 93 though. If you ever need to see a difference in octane, work with outboard engines, especially the older four-strokes.
VTsullyman Posted February 20, 2007 Posted February 20, 2007 The min is 91 thats why you felt no changes. 2007 DGM LGT 2003 Suzuki SV650S
DukeTrout Posted February 20, 2007 Posted February 20, 2007 Actually, 87 on a stock car wouldn't be so terrible:icon_surp. The stock tune runs extremely rich, and therefore with lower octane fuel, it is kinda like leaning the fueling out a bit. I mean techinically it isn't(More like raising the combustion temps), but it is pretty much the exact opposite of running racegas on a pump gas map. It isn't going to help, but actually hurt! Now, on any of the various Stg1/2 tunes, they pretty much have taken some fuel out, added boost, and also timing. So I wouldn't run 87 on any AP/Ecutek/Utec/OpenEcu without at least datalogging it a few times to ensure that you aren't upsetting the ECU. And to be really certain, I would flog it, then let it heatsoak, and try it again. Because under ideal cool/winter conditions, it might work great but in summer heat it could be trouble. Ultimately, 87 cannot compare to 93, if tuned for it. The engineer's knew full well that many will attempt/run 87, and have appropriately prepped the Ecu for it. Which is probably why they left 50 hp lying on the table in engine management... Ich bin echt viel netter, wenn ich nuechtern bin. Echt!
IwannaSportSedan Posted February 20, 2007 Posted February 20, 2007 Octane is not about rich or lean, it is about how easily it oxidizes, not how much of it oxidizes. The misconceptions here are amazing.... Oh, it works fine to put low octane gas in a turbo car... Sure. until the intake manifold cracks when the pinging that you didn't hear finally fatiques the plastic manifold comletely. Or some other thing happens. few pennies now for hundreds of dollars later, is about right. octane rating has to do with how easily the fuel that is there combusts, NOT how much fuel there is to combust. The car could be running relatively lean on 87 octane, or slightly rich, and the fuel still combusts too early due to intake pressure from the turbo, and coming in contact with hot metal in the heads. pressure and heat. pressure and heat. Octane has to do with how well fuel resists heat and pressure before it detonates. It isn't supposed to detonate in the intake tract, it is supposed to detonate under much higher pressure in the cylinder, when the spark plug makes it detonate. THEN it can be used for power. Detonation before that point just creates explosion pressure in the intake tract, and damages parts of the engine. Valves, valve guides, intake manifolds, intake tract valve butterflys, vacuum services, and even the throttle body and upstream, if the detonation gets severe enough. It still detonates early. The computer adjusts the mixture, timing and boost pressure in response to it, not in advance. Do what you want, but don't kid yourselves that you know that it is fine to do. If you don't know why to ignore some of the factory recommendations, you shouldn't ignore them. People ignore break-in and tire pressure, and fluid specifications because they know BETTER than boiler-plate recommendations, not because they know less. If they know less, they are gambling with their machines. sometimes you don't lose. in this case there isn't much prize to win. And fuel octane is one of those things, where you might survive it without catastrophic problems... but don't scorn and blame the car if it gets damaged outside of warranty, or if you shorten the operational life.
vet Posted February 20, 2007 Posted February 20, 2007 Slightly off topic but, I've heard that premium actually has less energy than regular. Point being that if your car runs fine on 87 you aren't gaining anything by using premium. Premium just resists premature detonation more/better than regular. I've run 87 on a few occasions with no issues although I wouldn't recommend it for most people. I agree with edmundu that Subaru (and all other manufacturers for that matter) build in a pretty big margin of safety just because they know some people won't use the good stuff. I believe most of the gains with stage 1 can be attributed to dialing out some/most of the safety margin that Subaru purposely built into their tune. And I don't believe premium will mess up injectors on vehicles designed for 87, that sounds like crap.
LordJim Posted February 20, 2007 Posted February 20, 2007 nd running 87 over time on a TURBO CHARGED CAR will most likely run into fuel injector issues. Why is low octane fuel going to lead to fuel injector issues? It's not as though low octane means low quality. Fuel injector issues? For real? - Jim
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