91 octaine is best you can genrerally get in Phx. ( except 2 stations dispencing 100 octaine racing fuel ) Plus, I allways have run the same exclusivly in evey car I have owned...if for no other reason, i dont really care how much gas costs, I can afford it.... I just put in the highest oct.

I hear pinging. Knocking is the sound you hear when a cat gets under your hood in the winter and doesnt get out in time when you start the car.. or maybe if the parking police put one of those tire locks on your car and you take off with out seeing it... but most likely, just let you oil level get low...( unless you have a 70's Plymouth Duster with a slant 6,, they just knocked )

Not seen negitve,, Oh yea, forgot,, my car ran fine till it started to ping for no apparent reason oooh like 5 days ago....OBTY,, In 110 deg,,, the horse will drink,,, trust me

 

[QUOTE=azminimanOBTY,, In 110 deg,,, the horse will drink,,, trust me[/QUOTE]
I like That.

Two side notes,

While trying to purchase a specific booster that has been working great lately, the clerks computer came up with a note saying not to sell it and that there is a recall on it. It uses a chemical other than mmt, so maybe carb doesn't like it.

While shopping for an alternative and reading all the "will not harm cats, etc..." labels I realized that maybe people are thinking of the old boosters that include lead. Those will ruin a cat.

 

Update on Pinging..... One can of Chevon techron injection cleaner...NO MORE PING... .... God I love that stuff

OBTW... still 110+,, The troff is empty...I better refill

 

My 2003 MCS has never pinged or knocked on Cali's 91-octane or even on 87-regular! I will say that recently, hubby discovered that using other than Chevron fuel in his Corvette, and in our old Isuzu Trooper, causes them to run VERY roughly. This is a new development, too. But I have never had any problems running 91-octane, even in 116-degree weather, with the a/c on full blast.


Clover

 

Out of curiousity, have you been seduced by the urdge to mod your MCS? (And if so, presumably your car runs fine on 91 octane post-mods?)

The reason I ask is that I have a 2003 Corvette coupe (LS1 engine) and after I had the power enhanced (CAI, larger throttle body, heads & cam, Iridium plugs & nology wires, headers and cat-back), it flat would not run on anything less than 93 octane. With the wonderful stuff that passes for premium in California, I am now faced with a requirement to blend in 100 octane unleaded racing gas to get to 93-94 octane for the Corvette. I am considering modifications for the MCS (principally a JCW kit), but am a bit hesitant if I will have to run 93 octane after the modifications.

 

I drove Wanda stock for the first 25+K miles. In 2004, she got a K&N Typhoon CAI and the M7 device. This May, at about 46K on her odo, she got the Alta 15% pulley and a Unichip. She is running great post-mods on 91-94 octane. When I was on this year's cross-country roadtrip and could get 94 octane, I'd fill her with 90 (mid-grade) at the half-tank point and had zero problems.

BTW, my hubby is the original owner/driver of an older (1991) Corvette, and he recently found that it only runs well on Chevron. He bought some Shell, and the poor 'Vette was bucking like a bronco...really running terribly roughly for the first time ever!

I hope this helps!:smile:


Clover