[SpdKlzU]

Hi all, I recently got my Cobb and am loving it. I just started with the Drive map and am very impressed and was curious about trying the Sport map, but I saw Cobb makes special mention in the Fuel Requirements section that Drive was designed for Arizona, California, and Nevada.

Does anyone know why this is? Is our 91 octane fuel of lower quality than the other states or is this based on cimate?

Thanks in advance!

[rader1]

Originally Posted by SpdKlzU

Hi all, I recently got my Cobb and am loving it. I just started with the Drive map and am very impressed and was curious about trying the Sport map, but I saw Cobb makes special mention in the Fuel Requirements section that Drive was designed for Arizona, California, and Nevada.

Does anyone know why this is? Is our 91 octane fuel of lower quality than the other states or is this based on cimate?

Thanks in advance!

Yes, it's due to the ACN fuels. The fuel is rated at 91 but i've seen some testing that suggests it's closer to 89 octane.
I dont know if e85 is available in CA, but if it is i'd try out a 20% mix try out sport or even aggresive. If no e85, then try some octane booster(NOS is highly recommended.) Hope this helps.

[rader1]

Here's a quote from travis that should help you, cheers.

Fuel quality is an interesting topic since it can vary from brand to brand and region to region. We have typically seen that Chevron, with their "Techron" aditive works the best as the Techron is a good burn-inhibitor.

California and fuels in the southwest in general are notoriously of low quality mostly for emissions purposes. These fuels are oxygenated, contain ethanol and are generally formulated to reduce tailpipe emissions. The flip side to this is that these are not ideal for "performance" driving.

Octane booster can be a good way to raise the octane of your local fuel and make it more friendly for high-performance driving.

The two products we have used are the NOS brand octane booster and Torco Accelerator. Both are non-street legal. The Torco will leave a nice orange coating on everything, but is not harmful to the engine.

To answer the OP's question, yes you could add octane booster and run a more aggressive map. We do this with custom tunes all the time, just make sure that your mixture of booster/fuel is consistent and that if you have to run without octane booster that you use a map appropriate to your fuel quality.

Travis COBB Tuning

[SpdKlzU]

Rader1, thanks a lot for the information! Damn fast reply for Christmas Eve too

I was worried it was an octane problem, but I can believe it - when I had a pretty modded DSM running 25-27psi I had to end up running a direct port meth injection setup to get around it. Here's hoping for that those clever guys at Cobb work out some way to trigger meth injection! Some new kits from Aquamist are looking pretty promising though.

[rader1]

There are meth kits readily available to integrate into a flash tune. They use a MAP sensor to start spraying meth at a user adjustable PSI.
My understanding of the way the N54 wastegates operate is that when you remove vaccuum they open and dump boost, so any failsafe that will cut vaccuum "should" work fine. However, you'd want to contact an expert to verify something like that.

[SpdKlzU]

Rader1, thanks again. Ideally I'd like to see Cobb have full bi-directional integration with a Meth setup to be really safe - after all, these motors are expensive! I used to keep a spare 4G63 motor around just in case I was a bit too ambitious with my tuning... a bit hard to do it with the N54

[elim11]

To be sure, you can run it and datalog to see if your car is happy

[rader1]

Originally Posted by elim11

To be sure, you can run it and datalog to see if your car is happy

+1 very good advice.
Whenever experimenting it's VERY important to datalog and review the results. Sometimes what feels better isn't actually helping the car.