I looked through my xb manual and I'm not really sure what type of gas would be best for my application. I want to concidering the fact my mods may have something to do with it (aem cai, dc header, rsr exhaust, jdm style grounding kit) I use 91 premium... would I be better of useing anything less (87 89)??

 

Run 87. Thats what the book says. All you are doing is wasting your money on any thing above 91. You only need premium when you are boosted or sprayed. So you have those simple parts, it did not increase the CR or anything. So no need for higher octane. About the only way you might need it, is if the engine knocks using 87.

 

thanks for the input

 

I had to put 86 in my car a few times, on a road trip. The car will run fine, even at real high altitudes (around 10,000 feet) on that fuel.

 

what is 91
we have 93 here in Tx

 

Yes & TX was also the first state that I saw 85 Most of the stations had 85, 87, 91 when I went through. I did not see to many with 93.

 

I run mine on 85 or 87, whatever is lowest octane avail at the pump. No knocking or any issues and I drive at altitudes of 5000 ft and up around Colorado.

 

I run 93 all the time here in CT. Except for those times that I throw in five gallons of 110.... But I am also turbo'd.....

 

would the type of gas you use result in better gas milage ??? just wondering...

 

I dont know where you stopped but most stations have 87, 89, 93, (and 95 or 97 at some 76 or fina station though it will cost you and arm and a leg)

 

No.

 

this engine is designed to run on regular unleaded fuel
anything more than this is a waste on a stock motor (not boosted!)
All the bolt-ons won't even stress the need for more expensive fuel (again**except boosted applications**)

 

the higher octane numbers do nothing for MPG....the numbers represent the amount of anti-knock additives that are in it...you dont gain any more power or anything... but if your bootsed or spraying you run less chance of detonation the higher the octane

 

uh oh, watch out for xACTLY, he might call you dirty names for saying that....... even though you are correct

 

yep, the higher octane gas is harder to ignite, and is for use in situations of high heat and pressure.

most cars have a sticker on the inside of the fuel door that tell you what grade to use. best bet is to stick with that unless your engine has been heavily modified (boost, internals that change compression and/or displacement etc.) even then, most turbo or SC kits will tell you what grade of fuel to use.

 

There was never any sticker to begin with... that's why I ask ... Thank you guys for your help .. Im gonna steal a turbo kit now