Running lower octane

[b e z]

Was wondering if anyone is running lower octane gas in their ms3 since gas prices are going crazy and if so does it run worse? Ive ran 93 since ive had it but gas is still rising.

 

[oaklandopen]

You can do 91. Don't do 89 or 87. They are not recommended and the second you start giving throttle with boost involved your car is probably going to be bucking and heaving like a bull in heat because the ecu is going to be on a never ending search for advanced timing it can't have with low octane

Save a few bucks now, pay a lot more later. Just drive less or plan routes with less traffic and stop lights

I'm planning on tackling the higher prices by biking to work a few days a week

 

[peavey]

I'm planning on tackling the higher prices by biking to work a few days a week

argeed!

 

[zrollo]

E85 convert? I want to do this badly.

 

[Tronspeed3]

I have ran 89 in the car before and my gas mileage went to s***, 91 is the highest we can get here in Iowa. I never really pushed the car with the 89 in it so I cannot comment to that. I figure I break even in paying extra for the 91 filling up less often.

 

[b e z]

I might as well stick with the 93, i dont want to be messing anything up. I would do the whole bike to work thing but my drive now is on interstates and takes me 15 mins in a car. I could take the town roads and get some exercise but i work at a bank and it would suck in dress clothes.

 

[b e z]

Also didnt think about the whole sweat factor to when i get to work.

 

[oaklandopen]

^^^hahaha....with my job, sweat is almost a requirement. mike rowe should do a dirty jobs where I work, if HIPPA wasn't a factor

 

[spdjnke]

learn to do hypermileing. or you can just run Royal purple to help get additional MPG...it has helped me greatly...

 

[oaklandopen]

According to my realtime mpg readout, I get better gas mileage doing 70 than 50

 

[b e z]

I recently changed what gear i run in on a couple mile trip down a highway. The speed limit is 55 and originally i was in 6th gear going 60 but when i approach some slight hills i fill like the car has to work to hard at that low of rpms so im running it in 5th, dont know if that will help a little with better mpgs tho.

 

[oaklandopen]

Difficult to say...

On the one hand you could say a higher gear yeilds lower rpms so less fuel used. But to me it also feels like I'm using more throttle so the lower gear at a better torque point may have better gas mileage than lugging in a higher gear

I would say the best way to find out would be find a long hill, and if you have an ap or dh or scan tool with live readout set it to show you fuel injector duty cycle and then approach the hill with cruise control set. Then just see the difference between gears

I'm thinking I might try that myself

 

[b e z]

That sounds like a good idea, il look at my ultragauge crap and see if i have the fuel injector cycle and post my results

 

[spdjnke]

I think you would be fine with a tank or 2 but after that I would go back to premium...otherwise your zoom zoom might go boom boom from knock.

 

[Kain]

I don't know your financial situation, but it really boils down to about only $3 a fillup...

 

[oaklandopen]

I don't know your financial situation, but it really boils down to about only $3 a fillup...

And I don't know YOUR financial situation, but wawa just raised their coffee prices

 

[wootms3woot]

I don't know your financial situation, but it really boils down to about only $3 a fillup...

AMEN, I hate when people b**** about premium compared to regular...our tanks are what 16 gallons max?? that comes to, on average, $3.20 a fill up more for premium. Honestly if you buy a turbo car and can't afford the extra ~$3 to put the right gas in it, then you should just sell it and buy a civic or corolla.

 

[flomulgator]

I've ran mid-grade and regular, both work fine. This isn't an old turbo, the ECU should be protecting the car from knock. Also, I believe (but could be wrong) that cars for sale in the US are required to be able to run on 87 octane. That being said I know tuned BMW's (M3's) run like crap on regular, but that's a totally different setup. Give this engine lower octane and it should just turn down the boost, like it's doing every 1st & 2nd gear anyways. Can't comment much on fuel mileage, as all grades of fuel here are laced with 10% ethanol all winter long, because one @#%$@ county requires it (not mine, but fuel distributors don't care), so it all sucks. Regular may be slightly less than 92 but not enough to be really noticeable or overcome the cost differential.

Come to think of it the 10% ethanol may be helping the knock/boost situation because ethanol has a very high octane rating (one positive to offset it's low fuel density). Either way I only put it in when I know I gotta burn a whole tank stuck in traffic or going slow, I'm feeling poor (which happens a lot these days) and the differential is in excess of 40c/G. Premium is now over $4/G here.

 

[peavey]

there is actaully a thread about some guy running 87 and its brought on a CEL and he had to spend cash to get get autozone crap, blah blah blah.

 

[peavey]

LINK
(yippy)