Greetings. I am a newbie who be very happy to find this site! :P

I have a stock 01 CLS. I'll do a search to learn the basic mods i should do, sounds like the headers area a must, but for here and now i need to find out what octane is best on a stock? The pumps here in San Diego go to 91, if there is a consensus best bottle of stuff to go 91+ I'm all ears.

Mods if this has already been gone over, but i could not find it in the search.

Yes, you need to put in nothing less than 91.

I use 93 @ Sunoco.

never use less than 91 and if the station has 93 get that

Pumps here max at 91.
My Q is should i go higher, and if so by what means?

you can put the new 93 v power by shell in your car

91 or better, However you can get away with 87 or 89. The computer will de-tune your engine to compensate. However you will loose performance & decrease gas milage. IMO it's not worth the few cents you save, so go with 91 or better.

Yeah nothing less then 91 should go in your CLS.

i just found a gas station by my house that has 100 octane and they charge 5.99 per gallon

Move to Philly.

Our pumps max out at 94 octane.

Yeah, they sell that near the race track. I think it's about the same price.

That would solve it.
What about these bottles of octane boost?
Does a stock 01 run better above 91?
Is there an octane rating that one does not want to exceed?

here its 93 at the pump but some race shops have upto 117 for ike 8.99 a gallon

Friggin California !!!!!!!!

Octane booster with a proper mix. Or buy 100 octane fuel and properly mix:
http://www.osbornauto.com/racing/blend.htm

Cali sux in terms of gas, yet, we pay premium prices. :ghey:

welcome to the site! and yes 91+ octane only.

Harsh winters + big pot holes for +3 octane gas? Hmmm...I'll stick to CA. You guys are by salt & rust over there.

Using a higer octane fule than you need adds no power, it's just a waste of money.

on weekends i go to jersey and i get ultra 94 for 2.15 gal

hey -- you can do better than that here -- I haven't paid more than $1.97 for 93 in weeks... one of the few perks of living in NJ is cheap, full serve gas.

Cool thank you. I will look at 76 for the 100 octane. Now, which octane # is best for an '01 CLS stock?

93 works wonders in my car

Winters aren't that harsh here. Now you guys get by earthquakes and wild fires.


I think I'll take my chances in Philly.

What do it say in your owners manual?

now when you ca guys get that quake that splits u off of the us i hope you got the prop and rutter option for your cl so you can boat it across to the rest of us.

"...91 or higher."
"or higher" is too vague.

Thus my question of what have y'all found to work well? Both from the tech and non tech angle. Have any of the tech types gotten some hardcore tech data that proves which is best?

im sure deep in jersey its that cheap.. i just go beyond the GWB the first sunoco on the Palisades PKWY... i did it again this weekend. the car really does respond better.

In answer to your question -- fill it up with premium, which as you say, is 91 in your area. You'll do quite fine and probably no better then those of us that fill with 92, 93, or 94 available on the east coast. The car is tuned for 91 octane fuel (according to the manual).

Don't worry about octane boosters. The over-the-counter variety (like at Pep Boys) actually do very little on raising the octane on a tank of gas. If you want to raise the octane you'll get better results if you mix 100 octane available at some 76 stations, or racing fuel (>100 octane) at race tracks.

Unless you want to run a FI setup at high boost, I wouldn't worry about finding different fuel.

anyone in the NYC area...
theres a station on Greenpoint Ave & McGuinness Blvd in brooklyn that sell 100 octane.. its like 5.00 a gal