I am getting a dual 91/E85 tune here shorty and have a few questions. E85 is plentiful here in San Diego. The nearest road course is a 3 hour drive (Willow Springs). The plan right now is a 29psi E85 tune, and a 24psi 91 octane tune. Since most of my time in the car will be tooling around, canyon runs, etc, I am thinking of keeping the E85 tune at 29psi and reducing the 91 octane tune to around 20-22psi for road course track days.

I am replacing my MBC with a 3-port solenoid, so just turning the boost down for track days won't be an option. I'm not worried about dyno numbers but don't want a neutered daily driver either...E85 being the daily driver fuel. I could put 20 gallons in the trunk for track days and head on up. I guess my question is, would 25psi...or a safe E85 boost number....be that much less fun as a daily driver than maxing out the turbo?

 

29 psi on a stock turbo is going to build a lot of heat up. E85 should be able to keep knock in check but I think there may be other issues with getting the heat out and killing turbos or melting plastic bits. 25psi will probably fine, but I would keep an eye on temps and check everything after the first session.

If you want more than 2 settings, get the equipment and bring your laptop with you to the track to reflash the low boost E85 map. Or flash it before leaving and switch back when you get home. With E85 I'd rather keep the low boost/91oct map on the side just in case I needed it.

 

Well that would allow me to have my cake and eat it too. Where do I start? I'm having the car tuned next month. Is there anything I need to tell them so I can switch tunes/lower boost at the track? I have a Macbook....assume I need a Windows based laptop?? Etc, etc!!

 

E85 does burn a bit cooler but the turbo itself trying to compress that much air is inefficient and make a ton of heat. Basically youll have a glowing manifold and turbine housing pushing it that hard which will cook the bearings and just about anything around it.

Its ok to run it like that on the street because its not run like that for long. Quick 1-2-3 and off. Takes no longer than ~15sec and then it can cool off.

For what you need to flash, thats a whole nother' discussion. Best to just start reading up on the basics of ECUFlash.

Really though you don't need to actually know how to tune it, just how to load a different file which you're tuner should be able to make you.

 

I would run e85 and about 24 psi of boost for track days on a stock turbo. You need to keep the turbo in a good efficiency window.

 

+1