Originally Posted by
hydro st170
I am new 2 cars and modifing them.What i was told at the start was that u can disconnet the imrc bix and then remap the ecu 2 let it no and adjust the ecu 2 have the lower torque.Its hard 2 get the information bout the car as i cannt get a book like the haynes books as they dont do them 4 the st170 i have even tryed over in america cause i hear they call it a svt.
il try to explain what the manifold does to help you understand.
on most cars they would have a set type of inlet manifold that from the butterfly to the engine is a preset length.. the distance the air has to travel to get to the engine(for reasons i dont understand) has an effect on how it makes power.
id assume ford for instance on say a 2.0 zetec engine designed the inlet to have a good balance of torque and bhp so stuck with a preset length. so that manifold has one path only to the engine. this will not optimise the engines potential for torque or bhp but will be the best of both worlds.
with a st170 the inlet is a 2 stage manifold that allows ford to give the best of both worlds. the manifold is switchable to a long length runner and a short. the imrc is the control unit that switches from short to long and back and forth as the engine requires.
if you disconnect it the default position is the short runner so you will be left with a loss of low torque until around 5-6k revs.
set it on the long runner and it will feel fine upto 5-6k but then lose the top end bhp.
there is no in between best of both world setting to it. i dont believe a remap can bring back the lost torque. ford could have saved them selves millions surely by chucking the imrc in the bin themselves and had the car mapped differently.
im not the best at explaining so it may help you or it may not
