sdsilverm3

What does that bolded statement mean to you??

You realize you do have a SUPERCHARGED motor?? When a forced induction motor does not adapt to lower octane what does that usually mean? Detonation, ping, knock. Whatever you want to call it. Since you're poking around on the internet go ahead and look up those three terms and the long term effects of DETONATION. Learn about what causes it and what is needed to prevent it.

Did you also intentionally "forget" these two paragraphs in the link you provided?

Extreme pressure inside the cylinders causes knock, which is the sound of the pistons literally rattling inside the cylinders. Too much too long can damage the engine. A little now and then won't.

The only modern engines that should really need premium are those with superchargers, which force-feed fuel into the cylinders. "You're driving along and just tramp the gas and the knock sensor cannot sense the knock fast enough in some cases," because the supercharger boosts pressure so fast, says Bob Furey, chemist and fuels specialist at General Motors.

Anyway, do what you want with your car. Just don't come back begging for help when you car starts running like ****.

taoh2

I don't believe 93 GAS. every pennis I save is a pennis in my wallet.
I using 87 GAS for all my car in the past 14 years and have zero issue:
1992 Lexus 400
1991 Acura Legend
1998 BMW 750iL
1998 S420
1997 BMW 749iL
1995 BMW 750iL

I put about 200,000 mile in those car combine. the S420 alone 80,000 mile in the last 6 year. still it run perfect, zero mechanical problem

and I don't feel I got less milage or performance on 87 GAS, I got about 26 MPG on my S420 at speed 70. 23 on 750iL

don't waste your pennis on those 92 GAS!

splinter

How is your collection coming?

boohooramblers

+1

ScottW911

That is an odd place to keep it/them but, whatever floats your boat........

greasybenz

The one time i let my dad borrow my 96 S420 he put 87 gas and it started ticking with a hit on performance. I was pissed to say the least and he was complaining about the price of premium over regular which back then when i had the car was 3-5 cents more then regular.

If you cant afford the gas get a better paying job or cut down on another habit to pay for the better fuel that the car requires. There is no point in having a luxury sports car and cheaping out on gas. I mean whats money?

bigben320e

Old thread, old debate. I think the OP just wanted to know if anyone had tried the experiment with regular gas and what were the results. He never said he was trying to cut costs or save money. It seems as though some people just ran with it and over the original question he asked. No one actually said yes I have tried this or no I did not.

True enough, it is foolish to put in 89 octane in a 93 octane car. It does make them run hotter, gas burns faster, and the car runs like crap. I would not do it.

On a experiment I did do, was with my 300M. It called for mid-grade (91 gas). At the time, premium was pretty cheap, so I ran with premium. The 300M was like a rocket, and I kept her babied. Now my brother, when I sold him the car, he runs it on 89 regular, and lo and behold deposits built up, 2 of the coil and plug needed a replacement in 6 months. The dealer told him "wrong gas caused this problem" I had the car for 6YEARS with none of those issues. It does make a difference. That should answer your question, but on a different car.

Zeppelin

So how did you get so rich when you cannot even spell?

MB_Forever

I just can't believe that despite all the facts provided and all the expert opinions from engineers, car manufacturers, internet articles, etc.... that people are still arguing that using crappy gas for an engine that is designed to run on premium gas is perfectly fine and does not harm the engine

These are not opinions, these are facts coming from people who designed and engineered the engines.

boohooramblers

+1
I just waiting for the '...well, you KNOW these car companies are in bed with big oil...' conspiracy theory!

ohlord

everyone should know that it is a high compression engine and if you use low test it will retard the timing and the mpg you normally get will decrease more then the 20cent savings per gallon.That plus the chance of burning through a few pistons.
Driving all those low compression jobs with 87 octane might have put a ***** in your wallet

TemjinX2

if you want something with 300hp that runs on 87, then trade in your c32 and buy a mustang. They run on 87 all day long.

If you can't run premium then go home or start walking.

c32used

Take it easy on me but I have a question...???

What if you use one grade down from Premium?

TemjinX2

Coming from high compression engines, I can tell you this.


Premium octane is designed for for high compression engines.

There couple of ways of making more power from a engine. Sticking NA using high compression pistons. This creates more Hp at the expense of torque with high redlines. Example s2000 with 120hp per Liter but little torque. You can increase torque by increasing displacement.

Creating high compression with force induction such as supercharger or turbo. You get the benefit of higher hp and torque with little displacement.
examples c32, e55, evo, sti

You can use lower compression with higher displacement to get power.
examples would be mustang 4.6L, corvette 7L.

First two examples you need combustion to occur later due to the higher compression, so thats why you need a higher octane gas.

This is also why you usually see sports cars and higher hp requiring premium gas.

if you put in a lower octane gas, combustion occurs before it should and can damage the engine.

The last example can use 87 oct because there a lower compression engine and make up for the less efficient use of combustion through increased displacement.

On the opposite side, putting 91 in a 87 vehicle won't make the car have anymore power. It merely makes combustion take place at a later time then its suppose to, so you lose a little bit of mpg.


the cliff notes to this is


USE THE GAS IT SAIDS TO USE IN THE FCKING MANUEL.

this is not intended to you c32used, but to everyone who reads this thread.

MB_Forever

Even one grade lower still hurts the engine.....

Because here in California there is no 93 octane available, I'm forced to sometimes use 91 (one grade lower) in my E63 and it has affected my car's performance on the track as well as on the streets. Also, when I had my C32, the car dynoed +8whp on 97 compared to 91 octane.

ohlord

I know you must have meant to include the little on that post ,right?
With all those parts and dyno time you are not really serious about saving a buck60 on a tank full o gas,are you
funny guy

DCarrera

I've never conducted the 'experiment' of poking myself in the eye with a sharp stick, but I'm pretty sure I know what the outcome will be.

Having seen the results of running an engine that was pining, first hand, I would not run anything except what MB recommends.

A holed piston comes along with a lot more damage. Sometimes the entire motor is slagged when the flame burns past the rings, super-heats a connecting rod and blam.... maybe I'll have to find the picture of the P-51 Merlin engine that was nearly blown in 1/2 after just a tiny bit of detonation started.

I'll just be sure not to buy any used C32's from down your way.....

ohlord

Please get real.Speculation?You put a real time scanner on a high compression mb motor and load it hard i.e going up a hill under acceleration with low octane fuel now look at the knock sensor values and the ignition values and tell me it is "Speculation"
Every time someone asks me what to look out for in a used Mercedes I always say ,inspect ,inspect,inspect....It becomes more of an imperative everyday when I read of noobs that know nothing about engine design talking about "Speculation" and playin Russian roulette with a ten grand jewel of an engine.
Please have the nads to tell the future buyer of your car just how well you maintained it
ohlord
Caution!
To maintain the engine’s durability and performance,
premium unleaded gasoline must be used. If premium
unleaded is not available and low octane fuel is used,
follow these precautions:
• have the fuel tank filled only partially with unleaded
regular and fill up with premium unleaded as soon
as possible,
• avoid full throttle driving and abrupt acceleration,
• do not exceed an engine speed of 3000 rpm, if the
vehicle is loaded with a light load such as two
persons and no luggage,
• do not exceed 2/3 of maximum accelerator pedal
position, if the vehicle is fully loaded or operating in
mountainous terrain.
Fuel requirements
Use only Premium unleaded meeting ASTM
standard D 439:
The octane number (posted at the pump) must be
91 min.
Sloneben,homego
Or maybe he has the progression of his posts and his ethics in representing his car for sale would indicate run from anything he has or will ever have for sale https://mbworld.org/forums/search.ph...nduser&u=55998
11 posts from ?use low grade fuel to loud growl coming from engine to car for sale Nothing wrong with it in top condition to price just dropped
I hope no member picks up the hoopdie
I love the "Very Fast" comment in his sales blurb
must be very fast limited at 2/3 throttle

Schizo0223

Gosh...
Here in Korea not all gas stations offer premium fuel...infact we only have 2 choices...cheap stuff or premium.

When I took my C32 for a drive out in the country I couldn't find any station with premium and had to fill up with the regular gas.

My performance immediately suffered and the gas mileage was noticeably worse.

So I guess the real life answer from experience is DON'T do it!

crazeazn

i love you guys are flaming a poster from a year ago. lol.

TemjinX2

its not to flame, its to inform.

People pay a premium price. For a premium car, to feed it crap. Makes no sense.

crazeazn

if they are stupid or cheap enough to do so, their fault not ours

mikekuriger

wow this thread has turned mean! I have run regular gas in mine with no ill effects at all. the knock sensor does the same exact thing if you run 91 or 87. it's still advancing the timing until it detects knock and then backs off. if you run 94 octane you'll have even better performance than 91 but saying 87 will damage the engine is about as likely as 91 damaging the engine.

91 is all we can get in california, but on the east coast 91 is definitely not "premium" fuel.

~Mike~

c32 dan

yo man how much you lot are payin for a litre of premium???i pay 1.24 in the uk(99 octane)=2.4dollers in the us...

Newzchspy