Hi,
I have been reading it is possible to swap the AFM for one from an early RX7 as it is larger and can give power gains. Seems to be a straight plug-in swap.
Has anybody here done this? Is it worth doing?
I read up on this a while back. It seems that if your running an aftermarket ECU and you’ve done a lot of breathing mods, It could be worthwhile.
The problem’s when you use it with a standard ECU, To stop your engine running lean you need to slacken off the flap return spring, But then it doesn’t always close completely. When this happens the AFM’s signal tells the ECU that there’s airflow, So the ECU adds fuel to keep the mixture right and your car won’t drop to the normal idle rpm.
To be honest though, The 1.6’s AFM isn’t that big a restriction, The 1.8’s is a little better but I seem to remember reading that they’re not interchangeable because you would need to work out a way to invert the signal it outputs to the ECU (As the flow rate increases, One goes from low to high resistance and the other goes high to low).
It’s a nice idea but from what I’ve read I would say it’s one of the mods you look at when you’ve done all the other breathing mods you can.
Scotty B
I have airflowed a couple of vane type afm. The afm becomes a restriction at about 6500rpm. Take it off and set to with a file and dremel. It is obvious wher the restriction is. It does improve top end.
The wealth of knowledge on this forum constantly amazes and delights me…