Injector Phasing...

[Mike Wesley]

On Sat, 10 Feb 1996, Timothy Coste wrote:

> 
> 
>    I'll stop discussing this unless there is a reply directly to my
> comments since this is getting way off of the diy category.  If
> you care enough about COVimep, transients, and cold starts, you're
> working for an auto manufacturer and not in your garage.  Or your
> WAY too optimistic about your 4 micro-processor's having nothing to
> do during idle times. :)  Sorry, I really enjoy my own humor late
> at night too much.
> 

Welp, count me as one of the 'garage' types who does care about 
transients, emmisions, part throttle driveability and WOT performance and 
does this type of work for himself and not an OEM. My company develops 
calibrations to pass EPA regulations for all 50 states in the US. I work 
mainly on Ford EEC-IV/V systems re-calibrating them for other 
manufactuers. I've been following the closed vs open valve injector 
timing and I too have spent many an hour doing steady state and transient 
testing. On a Ford, you can change injector timing based on speed/load 
which is VERY nice. I fire on a more closed valve at part throttle/light 
load for smooth peformance and reduced emmisions. I fire on a more open 
valve at high load/WOT for increased torque. During the WOT transient 
testing, and depending on the engine, I see a 0-10% torque increase by 
firing on a more open valve. Of course if you fire too late, your in for 
trouble later on. Since I deal with high performance, federal certified, 
street cars, injector timing is pretty important to me.
Mike...