Intake Runner Length

[Van Setten, Tim (AZ75)]

> Subject: RE: Intake Runner Length
> 
	Massive Brutal snippage

> Would it be safe to say you used 555's?.
> Would asking what for Op-Amps be OK?.
> Just 4 pots?.
> Bruce
> 
Sorry, no 555's in sight.  The box is broke up into two basic parts.  One
for the injector timing, and the other for duty-cycle (pulse width for you
digital types).
Injector timing is done by converting the input pulses from the coil (freq.)
into a dc voltage.  Next step is using a dc-freq. converter (PLL) to set the
rep. rate for the inj. timing.  I found that when I run the inj. at approx.
8% faster than what the engine is running, the bottom end and mid range is
fantastic!  If it is set to 1:1, it stumbles or hesitates.  I can
momentarily speed up the freq. of the inj., and/or increase the duty-cycle
for an accel. pump action, but it's not the same.  An Accel pump seems to
kill the off idle transition in a port inj. design.  I can also slow down
the freq. of the inj. (to eng. freq.) to lean out the idle if the pulse
width gets to narrow. (Remember we are using anywhere from 32 lb/hr to 60
lb/hr, low impedance injectors).
The TPS input goes thru different op-amps that the gain is controlled by the
engine freq, thus the different ranges, idle, mid, and top or wide open.
Did I help at all, Bruce?
Tim