jermzz

iTrader: (18)

So I bought a turbo car. Tuned on 93. Might not be able to get it tuned right away and all we have here in ca is 91.

I can throw a couple gallons of 100 in with each tank though from the local station.

question is, does it matter if im higher then 93? Is that gonna effect anything, or is it strictly related to timing / detonation just like in a all motor car? Is putting like 7 gallons of 91, and 3 - 4 gallons of 100 just to make sure im at atleast the 93 the car is tuned for ok?

Im new to boost.

I found a couple equasions for mixing octane, but no two seem to come up with the same rating.

thanks for the help.

TurboZ28408

iTrader: (18)

as I told you previously GERM


elevation and air density has a big factor to the AFR's of your vehicle and how well it runs.

jermzz

iTrader: (18)

im talking strictly from a octane point of view. Everyhting else is relativly close. I just need to be able to drive itif needed without ******* something up

ls1290

iTrader: (20)

Just 'driving' it around should not matter. At WOT, it can make a difference. How much boost is it making? If you do not want to get it retuned for the CA environment, buy a tuning tuner and bump the timing down a couple of degrees and you should be good at WOT.

MadIceV8

iTrader: (12)

Wiki:

"Octane ratings can vary greatly from region to region. For example, the minimum octane rating available in much of the United States is 87 AKI, and the highest is 93. However this does not mean that the fuel is different.

In the Rocky Mountain (high altitude) states, 85 AKI is the minimum octane, and 91 AKI is the maximum octane available in fuel. The reason for this is that in higher-altitude areas, a typical combustion engine draws in less air per cycle due to the reduced density of the atmosphere. This directly translates to reduced absolute compression in the cylinder, therefore deterring knock."

Pro Stock John

iTrader: (34)

Are you pulling out some timing around peak torque?

The BallSS

iTrader: (9)

Really doubt there's any significant difference between 93 and 91.....

mk3cn4

iTrader: (3)

My understanding of mixing 87 and 93 for example is that it ends up being an average of the two, so I assume that's may also be true with your 100 octane but I'm not sure.

93 versus 91, just "driving it around" should be absolutely no problem right now if you don't go WOT ( in my opinion based on my tinkering.) Certainly keep it out of boost.

If possible, get something that will allow you to watch for detonation (KR) and go for a drive and give it a test... and don't go WOT until you get some REAL good data on the 91.

It all depends on how aggressive the prior tuner was when he tuned for 93, and all the other variables like weather/humidity/heat etc.

But if it were me and I needed transportation, I would not hesitate to drive it non-aggressively on 91.

Pro Stock John

iTrader: (34)

And yeah you should run more boost and less timing given the fuel you want to run. At some point you hit a point of diminishing returns (14 psi and 5 degrees of timing lol?)...

TheWrathofDan

2009 post