el es tu

For street tunes this is all over the place - some use it while others do not for various reasons.

Supposedly it helps engine braking and fuel economy, but can add "jerkiness" to the car.

Im also concerned about engine and driveline reliability when leaving this on and driving the car hard.

Have any folks in the autox and rr forum just completely disabled or partially disabled it?

If it makes any difference, the car is paddle shift...

Thanks!

Ramo7769

I'm curious but not an expert. I talked to a friend of mine who is an OEM small block calibrator about this. He stated that Decel Fuel Cut Off (DFCO) doesn't make a big difference on engine cooling (makes sense, throttle is closed in DFCO condition). But it makes a big difference with catalytic converter temperature. Unburned fuel hitting an 800°F cat would cause it to heat up and potentially burn up the cat on track. DFCO keeps it cool. The OEM calibration will have a thermo-model for the cat that protects it under extreme conditions (otherwise GM would be replacing a lot of Corvette cats under warranty). They accomplish this primarily with a good fueling strategy (enrichment under heavy loads, dfco, etc.). When you tip in after DFCO, a good calibration (OEM calibration) should allow proper fuel puddle growth and give you full power immediately.

I personally would not eliminate DFCO if you have a catalytic converter. I plan to remove all of the cat related calibration if and when I eliminate mine in my C5 but am not touching it before then.