Injector Duty cycle calculations

[timsiford@hushmail.com]

FELP

I bought a new set of injectors (24lb SVOs) to replace my stock 22lb injectors. 
 The car is a 1990 IROC 350 with the 730ECM.  It has a 52mm TB, MiniRam,
 AFR heads, 218/224cam, 2800 stall, and 3.73s.  I switched to 24lb injectors 
because I was calculating 100+% Duty Cycles with the 22lb injectors.  Now 
that I have the 24lbers installed I am still seeing high duty cycles (90% 
at 6500rpms).  I am running a PROM where I used an injector flow constant 
of 28lb/hr and have the pressure cranked up to 50psi.

Diacom shows an injector pulse width value of 8.3ms at 6500RPMs.  Is this 
a 90% Duty Cycle?  I am using the following formula:

RPMS / 60(sec/min) / 1000 (ms/sec) * Pulse Width (ms)  * 100% = Injector 
Duty Cycle

Since the 730 is batch fire this equation appears to be correct.  However,
 I viewed some Diacom run from a '97 LT1 and saw injector pulse widths of 
10ms at 6500rpms.  Given that that ECM is sequential, I don't understand 
how those duty cycles could be so much less than mine?!  This car is even 
more seriously modded than my car (224/236 cam, AFR heads, manual, 58mm 
TB, 4.10s).  

Am I missing something here?  Is Diacom reporting wrongly?  Any help is 
seriously appreciated because I am getting ready to sell the 24lb injectors 
that I just installed (this past friday - two days ago!) in order to buy 
30lb injectors.

Thanx!
Tim


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