Whats the downside of running 101 octane

[tim_the_toolman]

will it harm anything in a mostly stock car? just a cam and exhaust?

 

[85GTlover]

Too much is just a waste.

 

[what_stanger?]

as long as its unleaded...

the only downside would be a slower burn and better mileage

 

[BlackFox5.0]

as long as its unleaded...

the only downside would be a slower burn and better mileage

How would it give you better gas mileage on a stock engine. If it burns slower you make less power (unless you running some crazy timing) and your engine has to work more. On a stock engine there is no point of running such a high octane. Unless you run a lot of timing, have a high compression ratio, or have some kind of forced induction, then your just throwing your money away.

It's very common for people to think the higher the octane the better it is for your car because it's more exspensive than normal "cheap" gasoline. I see it all the time, people putting 93 in a minivan to old 80's family cars. Why? They think it's better cause it costs more, amongst other reasons.

 

[what_stanger?]

i never said it will help him.

sure if you advance the timing a lot,-- run race gas, or if you use nitrous or have a forced induction engine, its always smart...

but isn't it a FACT that higher octane fuel burns slower? leaving room for more ignition timing advance...

given that it burns slower, wouldn't that yeild better gas mileage?

i'm not saying it'll be significant just saying better mileage.

 

[Ned]

Octane is the numerical measurement of a gasolines ability to resist detonation and pre-ignition. On a stock car, it is not really worth it to pay the extra money. I would only use it if you have some sort of forced induction, timing advanced, etc.

 

[tim_the_toolman]

we went to the track tonigh again and my buddy (who has a 93 gt) was wanting to better his best time. he thought 101 may be a thing try. seems like everyone at the track is using the stuff on all types of cars so i was just curious. i know on some cars the high compression, forced induction, or use of n20 forces the need to use a high octane product. he was worried about it harming his 02 sensors.

 

[siege]

I'd say the only downside is the extra pocket money

sometimes I even wonder if 91 octane (we have no 93 here) is even worth it, what with it being about $2.25/gal right now...

 

[blkstangman88]

i dont know about u guys and ur mustangs, but in my 88 gt, if i put anything beside chevron premium in my car, it misses and backfires, basicly runs like crap untill i put the good stuff back in, i do have my timing way advanced, but if the timeings anywhere else my car wont run right. anyone else with this sort of problem?

 

[thumper460]

The slower burn will mess with the sensors... but you have to run a lot for a long time. As for bennifits... NONE!! on a stock engine, and yeah, it almost cost the same a pump gas...LOL

Just me..........................

Thumper