Run 100 octane in a 2013 135is

[User594924]

What's up Im trying to go to the track soon I have a stock 135is I'm trying to run 100 octane is it safe or will I blow the seals thanks?

[EdP]

What's up Im trying to go to the track soon I have a stock 135is I'm trying to run 100 octane is it safe or will I blow the seals thanks?

Those seals are slippery fellas, I doubt you'd get one to hold still long enough.

[User594924]

Ok thanks alot but what about a mixture between shell 93 and 2.5 gallons of 100

[EdP]

ok, seriously - it's fine but unnecessary. the car will be quite happy on 93 and I doubt anyone could tell the difference. my only caveat if you do mix: buy the 100 at the track, so you can be reasonably sure it's fresh. years ago, a punky tank of 100 that I bought at a local gas station caused me all kinds of headaches.

[Bimmerman535i]

Ok thanks alot but what about a mixture between shell 93 and 2.5 gallons of 100

Why bother? Yes, you may make a handful of more powers. You are still going to have massive cooling issues.

[User594924]

You know what I'm not even going to mess with it I don't need the trouble right now if I mess the car up I do not want it to be somthing stupid like that thanks alot I'm definitely going to take your advice

[ZimDoc]

If you are drag racing the car sure why not. HPDE I'd skip it unless your tune NEEDS it.

Your vehicle will adjust to a point but after so much its not worth it. Also don't drive hard after that mixed tank because your DME will have to adjust back to normal fuel.

[PrinceE30]

I would like to cite that many local guys who often have CELs come up from time to time when autocrossing / tracking their cars, will run 95 or 100 just for the extra detonation protection and to prevent any issues that might arise which could cause ker-blamos. Just a thought...

[Subieworx]

Don't bother. You won't need it.

[JerryTX]

Side note: it will leave an orange or red residue on your spark plugs. No harm there but BMW would likely void your warranty since its evidence of non warranty spec fuel.

[dsobering47]

Try to find a 100% gas fuel station in your area....the ethanol in the fuel is what is killing the fuel systems. Puregas.org is a website specifically dedicated to tracking stations that sell undiluted fuel.

[PCarroll]

If you mix 100 race gas with 93, the car will love it. And it will make more power for sure. It may even run cooler. However, it's a lot more expensive. If it's "real" gas - not some voodoo octane enhancer - I don't see how it would hurt it. Do not put those home brew enhancers in a new BMW. You could do some very expensive damage. e.g. mess up the cats, O2 sensors, etc.

A lot of racers mix like this in an otherwise stock engine. How do you think we go so fast? Even a stock tune will adapt somewhat. It's not so much the octane. But race fuel just contains more energy that street gas.

And yes, ethanol sucks. It raises the octane yes. But it also has less energy (calories/gallon) than straight gas. From my experience, the loss of energy outweighs the octane benefit.

[JamesM3M5]

Those seals are slippery fellas, I doubt you'd get one to hold still long enough.

BAHAHAHAHAHA!!! That's funny.

100 octane mixes (1:4, or about 20% 100 octane unleaded) will clean up any individual cylinder timing corrections, especially when things get hot. The engine needs more timing to run cooler, and track use is definitely a great place to up your octane on the N54/N55 engines!!

Otherwise get a Vishnu FlexFuel setup, Cobb AP and custom tune, or some other tune that can exploit E85 concentrations over 20-30%. I am going with Vishnu FlexFuel this winter. High ethanol concentrations require low pressure fuel system upgrades, but they are a HUGE improvement for power.

One thing that's most remarkable aobut these N54/55 engines is that you practically practically blow them up from boost or timing issues. The engine management and direct injection are just too smart to let the engine go.