Getting a ZFG DMS tune with valved exhaust

[beezee]

Hello, I did the valved catback for the explorer st and I was curious in which mode should I be tuning the car? With the valves open or closed? I'd assume open for more exhaust flow but could the car make better power if it had more back pressure from closed valves? Thank you

 

[UNBROKEN]

No exhaust is adding any power, valves or not. All you bought was sound…tune it in whatever mode you like.

 

[2020FordRaptor]

Hello, I did the valved catback for the explorer st and I was curious in which mode should I be tuning the car? With the valves open or closed? I'd assume open for more exhaust flow but could the car make better power if it had more back pressure from closed valves? Thank you

Back pressure is mostly a myth. It won’t matter what mode you tune in, it won’t help flow at all.