thethirdman

I am a new driver (17) and just got a 1995 v6 mustang. I am really enjoying the benefits of driving stick shift, but I have a few questions. I am not sure what grade gas to use (regular,plus,premium) and was told that I should use STP gas treatment whenever I fill up and wondering if it really makes much of a difference.

Thank You

89stanglx

on my daily driver a 1990 jeep i just put cheap gas in it. in my mustang 89 stang lx i run 93 octane because i have the timing bumped up. in the past i would just run cheap gas and give it an occasional treat with a tank full of higher octane, and once in a while i would by a bottle of fuel injector cleaner in whatever vehicle i owned. I have heard that a lot of gas additives are a waste of money, who knows. Do a google search and let us know, i think a lot of it is just oppinions especially on a stock vehicle just do what the manufactuer recomends. No gas will hurt it and some additives your wasting your money.

Chopper

If there are no modifications to the timing and the cams are stock run the cheapest gas you can buy.There is no benefit to buying higher octane or more expensive gas if you don't have to.Higher octane has no benefit oher than resisting detonation.More expensive gas has no advantage unless you have too much money in your pocket and want to get rid of some of it.If your car pings or knocks then there's something wrong with the engine.This could be caused by deposits in the combustion chamber,spark plugs that are too hot for the engine,and oil burning.Deposits in the combustion chamber effecively raise compression,higher temperature plugs create a "hot spot" in the combustion chamber,and oil invading the combustion chamber lowers the octane rating of the fuel being burned.(Motor oil only has about a 40 octane rating,about the same as diesel fuel) Additives used every once in awhile can be helpfull in reducing intake valve and injector deposits especially if you do a lot of start,run,shutdown type of driving.Everytime you shut down the engine the fuel on the injectors dries into a varnish layer and any fuel still on the backs of the intake valves does the same thing.This causes a lot of cold start problems.I have found that additives work best when they have time to work,like at the beginning of a couple hour long trip.

83beast

yeah, no need for the high end gas. it actually is (in the least bit, but its there) worse. it takes a higher temp and compression to detonate it, so youre totally wasting money. i have a 83 and i run regular. i have the timing bumped up, and some other mods, and it runs fine on reg. dont waste the money.

JD1969

PLEASE stop saying stuff like this, it is not worse in way what-so-ever, there is no benifit for him with a stock V6 but there is no harm at all in running the higher octane (other than waisting money)