Steamboat

Greetings,
I DE a 750 hp 997.1 Turbo that utilizes a Fabspeed exhaust and hi-flow 200 cell cats among its many other modifications. I also drive the car on the street and generally take it for a long road trip each year to a favorite track. While at the track I generally mix a half-tank of Sunoco 100 unleaded race fuel with 91 octane unleaded pump gas which is the best available to us in Colorado. This spring the cats will be coming off and a test pipe installed. My question is whether I can then run Sunoco Standard leaded fuel, 110 octane, and whether that can be mixed with the unleaded pump fuel that got me to the track? Any other potential problems I should be thinking of? Thanks in advance.

Chris@Fabspeed

You will kill your O2 sensors running leaded fuel.

Mixing in 100 Octane unleaded is plenty "safetynet" for a tune that is only rated for 91 or 93.

stownsen914

Aside from the O2 sensors, the lead shouldn't hurt anything else once the cats come off. But lead and extra octane might also not be needed. They only help if your engine needs them. Maybe check with your engine builder. 750 hp!

Scott

Viperbob1

What they said plus 110 is not easy to detonate. Your ignition system needs to be damn strong to ignite the charge at pressure and high RPMs with lower rise time on the coils.