87 octane in a car tuned for 93
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From: Central WI (BFE)
SL55, ML500 & Acura TL
87 octane in a car tuned for 93
So I pull into the gas station to fill up the SL. Right next to me are two gorgeous twenty somethings I now know attend the University of Wisconsin. While I am completely preoccupied with them, I manage to put 87 in the car instead of 93. I realized what I had done, just as they drove off and managed to get about 4 gallons of 93 in the tank. I put about 14 gals of 87 in.
I know I deserve what I get for flirting with a couple of women half my age, but how concerned should I be about this? My car, I mean
I put a can of octane booster in the tank today and plan to stay out of hard pulls until I have gone through the tank. Any other suggestions?
I guess it is a good thing the diesel nozzle won't fit in the tank.
For those who don't know or if it matters, my SL is modded close to stage three and dyno tuned by EC.
I know I deserve what I get for flirting with a couple of women half my age, but how concerned should I be about this? My car, I mean
I put a can of octane booster in the tank today and plan to stay out of hard pulls until I have gone through the tank. Any other suggestions?I guess it is a good thing the diesel nozzle won't fit in the tank.
For those who don't know or if it matters, my SL is modded close to stage three and dyno tuned by EC.
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From: Orange County, CA.
one car at a time
Just drive the car gently and stay out of boost and you should be fine...If you start knocking, your car will just pull timing...That said, don't drive it hard or you could really damage your pistons if the knocking is severe.
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From: PALM BEACH GARDENS, FLORIDA
2004 MERC E55
should be fine. just drive "normal" and run this tank out. you may experience some unusual shaking when cutting car off or rough idle with this tank due to the 87 octane but if you have place a "booster" inside, it should "balance" it off. whenever i have gotten "bad" gas the car shaked when cutting off and during start up you can tell something was not right. made a point to never fill up at that particular gas station again. but "normal" driving until next fillup you should be just fine! no worries.
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Thanks guys. I am running a 178 pulley. I was thinking a casual cruise on the freeway at 70 mph and not much more than 2,000 revs would be a good way to burn up the tank of 87.
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From: Seattle
1992 911 C4, 2008 P2 E63 AMG (gone but not forgotten), 2007 SL65 Renntech
Do you have access to any 101 unleaded? It's spendy but 5 gallons of that in the tank should bring it back up or just be easy like the others say. I have not put any 101 in E63 tank like I have my Porsche to run 96-98 Octane. Porsche loves it though.
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03 E55 AMG, 06 Harley Road King Custom 06 Ram 2500 Cummins, 97 Firebird Race Car, 88 Cutlass Supreme
.Just run it out without getting into boost as others have said. Easiest, cleanest way to do it. Be glad they didn't ask for a fun ride in that sporty looking car of yours. Lol
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From: Southport, NC
E55
Go to the parts store and buy a bottle of NOS Racing Formula octane boost. A 12 oz bottle should get you to 91 octane very safely. You can add a second bottle and that should put you just over 94. I would just add 12 oz and call it a day since you added some 93 and had some in the tank already. You can also add "The Outlaw" brand but it has tested as not quite as effective and should end up about 1 to 1.5 less on the rating.
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From: Maryland
Eurocharged 2004 E500, Eurocharged ECU/TCU 2005 SL600, 2010 Caddy SwaggerWagon
Exactly why I keep a can of Torco race fuel concentrate on hand. Octane booster is crap, get some Torco for future transgressions. 
As others stated, you'll be fine. Just keep your foot out of it.
As others stated, you'll be fine. Just keep your foot out of it.
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2005 E55
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From: Central WI (BFE)
SL55, ML500 & Acura TL
As luck would have it, while I was driving home, a kid in an older WRX wanted to play. I didn't oblige. Lots of scoobies around these parts. I suspect he was thinking my car was a waste in the hands of an old F-er like me. Little did he know, I would have smoked his **** under normal circumstances. I hope to see him again.
I will definitely heed your sage advise. I am quite sure something such as this could happen again.
BY the way, I never trusted octane booster for some reason. Is the stuff just a marketing gimmick or what?
Last edited by cal1; Apr 6, 2013 at 09:26 PM.
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From: Southport, NC
E55
No it isn't a gimmick. The brands I recommended have been tested in an independent lab and proven to work (most boosters are next to useless though, not having enough MMT or ferosene to make an appreciable difference). I recommended these because they are easy to find and will correct the problem you have based on the assumption you are not planning on racing the car until you have cycled through this tank of gas. That being said, I personally have always added Torco before running at the track and agree it is one of the best out there.
Last edited by Alex Kapparos; Apr 6, 2013 at 10:37 PM.
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'06 E55
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From: Johannesburg, South Africa
2006 E55 AMG
Agree with all of this ^^^^. Our 95 octane is about the equivalent of 91 octane in the USA so most petrolheads supplement with octane boosters. Torco appears to be the preferred brand amongst those in the know.
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From: Chicago
03 E55 AMG, 06 Harley Road King Custom 06 Ram 2500 Cummins, 97 Firebird Race Car, 88 Cutlass Supreme
The over the counter octane boosters work EXCEPT when they say "raises your octane 7 points" they mean .7 not say 87 becomes 94. It becomes 87.7 only. That's the gimmick part of it. I believe the Torco brand actually really helps though. Most are just toluene.
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I actually have drums of pure toluene in my shop. I'm not sure if I want to try adding any to the tank though. Pure toluene is nasty crap. A couple years ago, one of my guys ran a fork from a lift through a full drum of toluene. He managed to get the drum in an over pack quick but a few gallons still got on the shop floor. He came into my office later and showed me the bottom of his boots. You could see his socks and almost all of the bottom of his feet. Toluene is a serious solvent.
Hey PA, I was going to try and burn the 87 out of my car, but it was raining out and I wasn't sure if it would be safe to do it in the garage.
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From: Southport, NC
E55
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Thanks for the info. So their claim of "boosting" octane is true, however misleading.
I actually have drums of pure toluene in my shop. I'm not sure if I want to try adding any to the tank though. Pure toluene is nasty crap. A couple years ago, one of my guys ran a fork from a lift through a full drum of toluene. He managed to get the drum in an over pack quick but a few gallons still got on the shop floor. He came into my office later and showed me the bottom of his boots. You could see his socks and almost all of the bottom of his feet. Toluene is a serious solvent.
Hey PA, I was going to try and burn the 87 out of my car, but it was raining out and I wasn't sure if it would be safe to do it in the garage.
I actually have drums of pure toluene in my shop. I'm not sure if I want to try adding any to the tank though. Pure toluene is nasty crap. A couple years ago, one of my guys ran a fork from a lift through a full drum of toluene. He managed to get the drum in an over pack quick but a few gallons still got on the shop floor. He came into my office later and showed me the bottom of his boots. You could see his socks and almost all of the bottom of his feet. Toluene is a serious solvent.
Hey PA, I was going to try and burn the 87 out of my car, but it was raining out and I wasn't sure if it would be safe to do it in the garage.
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From: Central WI (BFE)
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Thanks Alex and everyone else. I threw a bottle of NOS racing formula in. Did some casual driving today. The problem is, the damn tank seems like it is lasting forever. It is amazing the gas mileage our engines can get if you keep your foot out of it. I let a mini van and a Prius pull a hole shot on me while getting on the freeway today.
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So I pull into the gas station to fill up the SL. Right next to me are two gorgeous twenty somethings I now know attend the University of Wisconsin. While I am completely preoccupied with them, I manage to put 87 in the car instead of 93. I realized what I had done, just as they drove off and managed to get about 4 gallons of 93 in the tank. I put about 14 gals of 87 in.
I know I deserve what I get for flirting with a couple of women half my age, but how concerned should I be about this? My car, I mean I put a can of octane booster in the tank today and plan to stay out of hard pulls until I have gone through the tank. Any other suggestions?
I guess it is a good thing the diesel nozzle won't fit in the tank.
For those who don't know or if it matters, my SL is modded close to stage three and dyno tuned by EC.
I know I deserve what I get for flirting with a couple of women half my age, but how concerned should I be about this? My car, I mean
I put a can of octane booster in the tank today and plan to stay out of hard pulls until I have gone through the tank. Any other suggestions?I guess it is a good thing the diesel nozzle won't fit in the tank.
For those who don't know or if it matters, my SL is modded close to stage three and dyno tuned by EC.
My Dad said you only have enough blood for one head.
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From: Central WI (BFE)
SL55, ML500 & Acura TL
