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octane rateing

1957 Views 14 Replies 7 Participants Last post by  barry putnam
I have recently bought a 1995 s320v. I notice the manual calls for 91 octane fuel, claiming any less will damage the catalitic converter. It is not a major problem as I didn't buy this car to save money. I am curious however if 91 octane is realy necessary.[:)]
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I have recently bought a 1995 s320v. I notice the manual calls for 91 octane fuel, claiming any less will damage the catalitic converter. It is not a major problem as I didn't buy this car to save money. I am curious however if 91 octane is realy necessary.[:)]
Cheap gas will do you no good. 91 rating is there to avoid engine knock.

Why feed her something she dosent want to eat?

///S320
[:D]cheap is relative of course. I paid $3.50 for a litre of water in a Las Vegas hotel a couple of days ago. On that scale $.76 for a litre of gas is dirt cheap.

However that is realy not the question. Does the car have a sensor that tells it what octane rateing is in the engine? I am more than willing to give a girl anything she wants so that I get the performance I want. Still, will she perform just as well for a hamburger as for a steak dinner ?

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I am more than willing to give a girl anything she wants so that I get the performance I want. Still, will she perform just as well for a hamburger as for a steak dinner ?
You are funny! [:D]
Actually it does not have a sensor to detect cheap gas. However, people have told me that the check engine light sometimes appear if lower octane rating is used (iam not fully convinced of that though).

I always use 93 grade, as in chicago thats the best you can get. If you want, you can try the medium grade gas and see the performance. 93 burns fast, hence you get more performance without engine knock.
The engineers in Germany did not recommend the use of 92 or 91 just for the kicks, its there as the engine needs it.

those were my 2 cents!

(nice car by the way!)

///S320
///S320:
I have seen your car and am most impressed with the shine. My neighbours have suggested I enter a 12 step program before I become too compulsive about the washing and waxing. The pic was before the wax job.
Barry
Re: Re: octane rateing

93 burns fast, hence you get more performance without engine knock.
///S320
Actually, ///S320, 93 octane burns slower than 87 octane. Higher octane gas is simply normal gas with additives used to retard the ignition of the fuel, and thereby prevent the knocking.
yup, thats right. After re-reading the manual and noticing the 91 octane rateing mentioned in a number of places, and also the notice on the fuel guage, I think i will just comply with the 91 octane minimum and have done with it.

Barry
Octane

I have a 1994 S320 and I have been using 87 octane Exxon for about 2,500 miles with no adverse effects so far.
I use 95 octane regularly and the engine shows no ill effects. Every 4th or 5th tank I fil...

I use 95 octane regularly and the engine shows no ill effects. Every 4th or 5th tank I fill up with 98 octane as a precautionary measure.

I always stick to 'branded' petrol stations like BP, Shell, Esso and Texaco. I steer clear of cheap supermarket stations as I have heard they do not add certain essential additives to 95 or 98 octane fuel.
octane

In Vancouver the highest octane available is 92. And that only at chevron stations. What is the 95 98 octane, is it full of alcohol?

Barry
[?]
a quick search on the internet will show you what the benefits of a higher octane level ar...

a quick search on the internet will show you what the benefits of a higher octane level are.
The lowest we get in the United Kingdom is 95 octane. This is regular unleaded petrol.
Then we have 98 octane which is classed as super unleaded. This is better for older engines, high performance, turbo charged and other cars which rely on the fuel to lubricate the pistons a bit like old leaded petrol. When running on 98, cars return better MPG and faster performance.

We also have LRP wich is Leaded replacement Petrol. A few years ago the sale of High Performance leaded fuel was stopped and LRP was put in its place. This fuel contains extra additives that replace the graphite which was found in leaded fuel.

We also have LPG (Liquid Petrolium Gas) and Diesel at most of our pumps.
octane rating

thanks for the info.

Here is the web site for the Ballard fuel cell which runs on hydrogen.

WWW.ballard.com

Barry
Here in Indiana, we get 93, I have seen 94 in Michigan before. Well, as long as it's over...

Here in Indiana, we get 93, I have seen 94 in Michigan before. Well, as long as it's over 91, I guess I am okay.
..

Steak dinner? Pfft. I think your car right now is thinkin 'what?!?! steak dinner! i want caviar!!'.. at least this was the case for me last summer when i went on vacation in my 300E. I was in montana, in a real rural area. I HAD to put 87.5 in my poor poor baby. Ohhhhh she didnt like that. As soon as I got to billings I filled up with 93...
octane rating

Andrew:

[:(]I filled up my 1971 pontiac firebird formula 400 at a pump that had 10% ethanol and advertised 100 octane. So I thought it would be great for my 330 hp 400 c.i. engine. Went straight home and parked overnight. Next morning had a hell of a time starting the car, forgot about the fuel by then of course. On the freeway on ramp punch the gas to blend-in in front of some traffic. It sounded like gravel hitting the hood of the car from all the pinging. And no "GO". Usualy this car excelerates like a jet! Just about got run over.

That night siphoned the ethanol out.

Barry
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