Hey guys, I had my car in a body shop for a few weeks getting my 99 spec bumper on, and I had left it there with almost no gas(stupid on my part). When I had it delivered on a flatbed to my house, it had about a 1/8 of a tank of gas. I started it, and it was running real shitty, and when I'd rev it past 4k, it would come back down and stall. I went to the shop and asked them what gas they had put in, and they told me 87. Now my dilemma... Should I take the car to the nearest gas station and fill it up w/ premium, or use octane booster for the last 1/8 of a tank? I just dont want any percentage of this shitty gas in my next tankful, and if I fill it up now, there will still be some percentage leftover when I fill it next. Any opinions will be nice to hear, Thanks! ~A-Rod

 

I thought it wouldn't be that big of deal to put 87 in an FD on accident...

I vote for filling it up with premium to dilute the 87... maybe get

2.5gal 87 + 17gal 93... should work out to a safe(r) octane...

I'm no expert though...

 

Hmmm,
ideas/suggestions...
-maybe disconnect the vacuum line from the turbo so you're not boosting
-mix in a bottle of octane booster
-top off with the highest quality pump gas that you can

The gas stations where there is one line for all the octanes, when you fillup you usually get a gallon or so of whatever the previous customer had. So chances are if they had 87 and you fill up with 93, your still gonna get 87 in the mix...so I wouldn't be too concerned with whatever is remaining in the tank after you fill up with 93.

Those are my thoughts...

~CYD

 

what kind of setup are you running? mostly stock engine wise? I wouldn't drive it with the lower octane gas either way, I would go get a gas can and fill it with premium (if you have a sunoco by you splurge for the 94 octane ). Go back and put it in your rx7, THEN drive up to the gas station and proceed to fill it with premium. The mixture won't be an ideal 93 (or 92 depending on your area) octane but it will be closer to what you want to run.

 

Just fill it up with premium. The octane booster isn't going to do squat.


If you want to be **** about it, you can get 2 gallons of premium in a gas can; climb under the car and undo the screw on the bottom of the fuel tank to drain it; add your 2 gallons of premium in; then drive to the gas station and fill it up.

 

I will be very surprised if the gasoline is causing your problem. I have used 87 octane on occasion and it ran well. The timing retart should work if it senses a knocking. I don't know what mods you have, so it is difficult to pinpoint the cause. On my 87 turbo sometime ago. got a bad batch of gasoline, and it ran like you are explaining you have with yours. My reccomendation would be to fill it up with premium gas and try it.

 

yeah if your going to drain your tank, dont forget to go get gas first... dont ask me how i know.

 

Just put a can of octane boost in the car, shake the car as best you can, crank it up, when the idle smooths out, gently drive to a Shell station & fill it up with premium. Or, unhook the fuel supply line under the hood, extend it to a 5 gallon can and turn the key to the run posithion, it won't take but a couple of minutes, if that, to drain the tank.

mike

 

Hopefully they didn't try to joy ride in your car with the cheap gas and cause any internal damage to the motor...

I'd just ill it up with your area's premium and drive easy on that tank. Then on the next fill up drive how you normally would as it shouldn't matter at all by that point.

_Kris

 

The car should still be able to idle with 87 octane, shouldn't it?

I wonder is something worse is the problem...

 

Out of boost, 87 octane will have no ill effect. It should actaully run a little better in vacuum, just don't boost with it.

 

Fill it with a few gallons of premium to dilute the crappy gas and mix things up. Buy a cheap siphon at any auto parts store. Siphon everything you can out of the gas tank. Refill with fresh premium gas. You'll be fine.

 

hell yeah it should, I filled up literally a couple of times back in the day with 87 octane. The car ran fine with no problems. I should point out that the car was 100% percent stock at the time hence no real danger of detonating.

 

I'd start it and let it idle in your driveway for a coulpe hours... drive around town at 1/10th throttle, whatever, to stay out of boost but drain the gas off...


unless you can actually get 94 in your area, then just fill it with 94 and don't worry about it.

 

Don't do this.



Just go fill up with some BP 93 and don't boost more than 5 psi for the whole tank, and then go fill up and you'll be fine.

 

yea octane booster will only bump up your fuel to .1-8 octane from what i understand so if u have 87 octane in there and u put octane booster it will only bump up your octane to 87.8 or whatever it says on the bottle. not worth it.

 

As others have said, the car should run fine on regular gas. I wouldn't boost on it, but it should idle and drive normally just fine.

You should be OK to fill the rest of the tank up with premium.

 

Exactly. Lower octane gas should perform identically to premium until you get into boost. In your case, stay outta boost until you burn the old gas off. Octane booster is not really going to do anything for you.

The fact that the car isn't running right at idle or up to 4k suggests you have another problem. Hopefully it's not engine damage from the low octane gas and hotrodding.

Dave

 

While this works really well on piston engines, the knock required to set back timing is often enough to damage apex seals. It's not an effective safeguard on boosted rotarys.

Dave

 

At idle and cruse 87 octane will not affect anything. Unless the fuel they added was contaminated(ie water) then you shouldn't be experiencing any problems. Just fill it up with 93 and see. If it still performs badly then you might have bigger issues.

 

just fill it with premium, you will be fine.... just hope whoever last drove it with the 87 octane didnt go joy riding.... If you are really concerned, go to the paint store and pic up a gallon of toluene, add it to the tank and you should be at or more than 93 octane, depending on how much 87 is in there... toluene is the main ingredient in most octane boosters, and has an octane rating of 114... i run a mixture of toluene and c16 in my tank all the time at over 20 psi of boost on my t78...

 

I just want to say it's amazing at how scared people are of blowing an engine, especially if they are just cruising around and not boosting. With that said just go fill it up because even if you have a 1/4 of 87 and fill it with 93 that would equal 91.5.

 

I didn't say anything about blowing my engine, I said it was stalling. And to tell you the truth, I think the body shop did do some joyriding with it, only because they seem "too" nice about everything, like trying to make me happy now so in a month or so when I start driving it I won't blame them for it. But I drove it about a quarter mile to the nearest gas station, and filled it with 93. It's not stalling anymore, so I'm curious to how this somehow made a difference when some of the above posts said it wouldn't? The body shop uses their gas out a their own large tank, maybe it had water in it?

 

I would bet you're right...

If new gas fixed the problem... & the shop has their own tank... it's probably got water in it... you should advise them of this (although they probably already know)...

 

That's possible, or that it was just plain old. (I dunno if old gas = absorbed water, that's another subject). It's good that the new premium made the problem go away, and you don't have any signs of engine issues.

Dave