Author Topic: How many of you run 87 octane fuel? (Read 40766 times)

sheepdog · « **Reply #120 on:** May 20, 2008, 02:20:20 AM »

Quote from: christophbmw;49723

Sheepdog, i love your posts, very educated compared to what most other people are saying.....but i have to disagree with you on your last post. i think the E30 is a cheap car for what you get, they dont cost much to maintain, they are fun to drive....and compared to most japanesse cars, they are very cheap, the only thing that makes most japanesse cars "cheap" to own is if you dont do regular maintnece on them they still run, BMW's on the other hand need there attention, thus, to the general public....they are "expensive" to own (because most people dont take care of their cars). Would you agree?/QUOTE]

Thanks that was sort of my point. Buy-in is pretty similar, to a point, for the same money you will typically get a nicer Japanese car. An "okay" e30 is cheap or similar in price to a decent Japanese car, a nice one is up there and on the rise. Upkeep however is way higher on these compared to Japanese cars. These cars were designed to wear out, Japanese cars are designed to live forever.

I never though of a BMW as a cheap beater, they are far too delicate for that.

Cheap BMW's are like cheap Ferrari's... "Wow a cheap 308! It only needs the fender fixed." Then you realize that fender repair costs more than the car in good condition (sadly enough, this is true about them).

mkodama · « **Reply #121 on:** May 20, 2008, 02:29:11 AM »

Some very good info and opinions being posted here!

Quote from: sheepdog;49686

And I never knew there was a rule that site admins could not be salty from time to time. I thought they were human just like the next person.

Usually other site admins get moderators to do their dirty work for them.:p

tinindian · « **Reply #122 on:** May 20, 2008, 12:28:28 PM »

Those of you who think it's a cheap car and you can run it on whatever crap you find and don't believe it's worth maintaining properly, I thank you. Because of you my well kept 1991 318is will be worth more money sooner.

mkodama · « **Reply #123 on:** May 20, 2008, 04:56:25 PM »

Quote from: tinindian;49753

Those of you who think it's a cheap car and you can run it on whatever crap you find and don't believe it's worth maintaining properly, I thank you. Because of you my well kept 1991 318is will be worth more money sooner.

You are a smart person!

xwill112x · « **Reply #124 on:** August 21, 2008, 09:38:21 PM »

Quote from: sheepdog;48938

If you read your manual you will find your way of driving your 318 is not good for it. The manual tells you you need to get it up above 3k regularly. In fact they give a ratio of how much above and below you should spend.

These cars were meant to be flogged, not granny shifted.

As I said, am sure you can get away with it, but it is not worth it to me. Too much risk.

I have no idea about the 12 miles, but if that were true, I would have just been on fumes. Most cars with a light like that come on around 1-3 gallons left.

it has 1.6 gallons left...thats what the manual says

batsbats · « **Reply #125 on:** August 23, 2008, 03:19:00 PM »

As a random update, I have been gradually running octane from 91 to 87.

I normally just half of 93 and 87 at the pump, since Jersey has options of 87, 89, and 93. Only exception I have seen to this is Sunoco that has 91 also.

This pass fillup, I said fudge it, and filled it with 87. I WOTed it several times and cruised around for a while. Drove up to NYC, and had zero problems. The other day, it got pretty hot outside. The idle started to freak out, but I had that issue on hot days with 91. Later that evening, the idle returned to normal.

If I ever plan to run the car hard like at autox or the track, I would put 91 or 93 in it. Otherwise, I don't see any problems with 87.

Hodge · « **Reply #126 on:** August 23, 2008, 08:55:19 PM »

I ran 89 in my 95 318i (M42) for quite awhile without any problems. I switched to 93 and it just feels better. Hard to explain. The motor just feels happier to have the higher octane rating. BMW engineers their cars to run a specific way.

Also, I like to rev the M42 any chance I get, and I would not want to do that here in Florida with 87.

colin86325 · « **Reply #127 on:** August 25, 2008, 10:33:59 AM »

Quote from: Hodge;55366

I ran 89 in my 95 318i (M42) for quite awhile without any problems. I switched to 93 and it just feels better. Hard to explain. The motor just feels happier to have the higher octane rating. BMW engineers their cars to run a specific way.

Also, I like to rev the M42 any chance I get, and I would not want to do that here in Florida with 87.

The E36 has knock sensors, so when it detects pinging with the lower octane, it pulls the spark timing back, which usually results in less engine power. When you put the proper octane back in the tank, the car was able to run with optimal timing.

tjts1 · « **Reply #128 on:** August 25, 2008, 11:56:41 AM »

Oh no 87 octane killed my engine!!!!

Just kidding. 153k miles and counting on 87 octane. I'll be sure to post here when i kill my engine using the wrong fuel.

E30_318is · « **Reply #129 on:** August 26, 2008, 05:46:20 AM »

I only ran 98 octane fuel (chipped m42).We dont have 87 91 and 93 octane fuels here.:p

colin86325 · « **Reply #130 on:** August 26, 2008, 08:21:14 AM »

Quote from: E30_318is;55507

I only ran 98 octane fuel (chipped m42).We dont have 87 91 and 93 octane fuels here.:p

Your octane is probably measured in RON units, while ours is measured in AKI (RON+MON/2).

98 is probably the equivalent to 93 AKI.

christophbmw · « **Reply #131 on:** August 26, 2008, 02:43:32 PM »

dont forget if you live over say 4,000 feet above mean sea level (MSL) 87 octane will be the same as 91 octane because of less oxegen. When i lived in Taho (6,300 MSL) i ran 87 no problem.

EN318isPDX · « **Reply #132 on:** August 26, 2008, 02:58:41 PM »

Quote from: christophbmw;55525

dont forget if you live over say 4,000 feet above mean sea level (MSL) 87 octane will be the same as 91 octane because of less oxegen. When i lived in Taho (6,300 MSL) i ran 87 no problem.

Is there a sensor that tells the car if its above sea level? A friend with an E30M20 told me if he unplugged that sensor on the dyno he gained +2 hp

mkodama · « **Reply #133 on:** August 26, 2008, 08:13:58 PM »

Quote from: EN318isPDX;55535

Is there a sensor that tells the car if its above sea level? A friend with an E30M20 told me if he unplugged that sensor on the dyno he gained +2 hp

As opposed to being below sea level? :confused: Most cars are made to be above sea level. Either way, in the case of the M42, it doesn't really matter. The amount of fuel that goes in is just calculated by the intake air temp sensor and the flappy air flow meter.

I'm pretty sure there is no sensor you can unplug and gain hp.

The closest thing I have heard of was in the US variant of the Mercedes 190E, there was a resistor that retarded the ignition timing slightly to compensate for the not so good gas we had in the US back in the 80's. Then again, I have never seen any hard evidence.

EN318isPDX · « **Reply #134 on:** August 26, 2008, 08:39:33 PM »

Quote from: mkodama;55551

As opposed to being below sea level? :confused: Most cars are made to be above sea level. Either way, in the case of the M42, it doesn't really matter. The amount of fuel that goes in is just calculated by the intake air temp sensor and the flappy air flow meter.

I'm pretty sure there is no sensor you can unplug and gain hp.

The closest thing I have heard of was in the US variant of the Mercedes 190E, there was a resistor that retarded the ignition timing slightly to compensate for the not so good gas we had in the US back in the 80's. Then again, I have never seen any hard evidence.

Blah blah blah blah how can an air temp sensor determine your altitude? If an M20 has a sensor for altitude why wouldn't our engine?