Exhaust Manifold/Heaters

[Andreas]

Hi,
Has anyone installed an aftermarket manifold?
The problem is if i remove the catalysts what happens with the sensors. I heart that in some cars you can trick the sensors.
Has anyone done this before?

 

[un1eash]

From what ive heard its pointless and any performance gains are minimal unless your doing other big mods.

 

[ga41]

From what ive heard its pointless and any performance gains are minimal unless your doing other big mods.

In certain cases the benefits are quite good. USA M's have an extra set of catalytic converters on the exhaust manifolds so they're more restricting than our Euro one's. Those who switch to European or other after market manifolds like Supersprint's report around 20-25bhp boost in power but have to flash the ECU to kill the inevitable check engine light or custom install sensors so it works without a flash. (more info here)

Andrea's Z4 isnt an American M though so i would agree with you mate in that the gains would probably be slim. Maybe someone with some actual handσ on experience can provide some more useful information.

Either way καλή τύχη φίλε Αντρέα!

 

[Andreas]

Ι didn't knew you can flash the ecu, I only heart that you can put the sensors deeper in the tube and avoid the check engine.
I will definitely go for it, i think supersprint is the best choice.
ευχαριστώ για το link φίλε.