i want to change my tune with predator tuner. i', running the 87 octane program right now and i want to unpgrade to the 93 octane. what i need help with is how low should i run my tank before putting some 93 in. I've never changed gas octanes before.

 

Fill it up with 93 octane when the gas tank warning light illuminates on the dashboard. There will be approx. 2 gallons of 87 octane left when that happens.

 

I just switched from 89 to 93 w/ my SCT XCAL II tuner. I drove til the the dash computer said 2 gal. to empty. I reflashed the car while I sat there at the pump. It took approximately 1/2 block until I could see the difference.

 

thanks for the info guys!