ATI Supercharging

[Frank Parker]

> 
> I'm running an aftermarket intercooled supercharger on a 1.6L Mazda Miata.
> Max boost 12psi, using 93 octane fuel, higher when I can find it. The system
> uses a boost-controlled variable fuel pressure regulator and an MSD spark
> retarder.
> 
> 
> I am considering replacing the MSD spark retarder with a knock sensor
> package that also contains an LED oxygen-sensor monitor. But it isn't cheap.
> 
I have a lot of experience using those fpr and msd boost retard. The first
thing you need to do is find out if you are rich which I suspect. The O2
sensor does put out a voltage when changes very little from rich to very
rich unless you buy expensive $2500 UEGO sensor/electronics package. You
need to dial in the a/f ratio better and it is hard to do with fpr. Can
adjust to be ok @ 5psi, then off @ 12psi and reverse. There are some new 
electronic controllers to chg fuel press with boost but much more 
controllable. 
Hook digital voltmeter up to o2 sensor and monitor while driving. Will
jump around but average about .5 during cruise. If lift throttle will drop
to 0 as cpu shuts off fuel and @ wot should be about .8 volts. 
I have lots of other things you can do. email mail back if interested.

PS. The msd retard is a dumb system that depends on you to hear knock and
it is hard to do. You need feedback knock retard like factory systems 
available from J&S in the aftermarket.

Frank Parker
>