UPDATE, Swapped to carb to rule out ignition.. Holley 4160 - 1850

[olbap <olbap@mail.mia.bellsouth.net>]

Basically convinced my friend to let me try out his carb, i kept the
computer dist in there, plugged inthe TPS again 

went for a spin, zero tuning on the carb and geeez the low end sucked
compared to the tbi.. but my gawd it hit 4000 rpm and the nearest thing that
came to mind was when the millenium falcon hit hyper space, it pegged the
tach in like .4 nanoseconds and i let off even though it wanted to keep
going, probably beyond 6500 but I wasnt about to find out... drove around
for like a half hour and thought the 75 or so horsepower gain on top was
uhm.. lets just say, Neat :)


So, i should have trusted my gut feeling rather than that crappy o2 sensor.
I didnt get to do any real tuning before it started raining outside today i
did crank up the fuel pressure just to see what it would do on the top and
it seemed to rev up to about 5400 or so which wasa good improvement


What really has me here is this whole thing with base pulsewidth.. it simply
cannot be right.. theway I understand it is that youd always lower it the
larger the injector is in relation to the motor using the formula.  Now if
this were true then the more hp/ci you had the lower your BPW would be since
that motor would require larger injectors.    I have found however through
adjusting BPW that it does nothing to "recurve" the fueling scales at all
its more like just a cut of fuel across the board.. I might be doing it
wrong which brings metoanother question.. do you calculate bpw from
theinjectors static flow rate or at 80% duty cycle?  perhaps not as
important I guess, but anyways,   using mycurrent bpw calculations it seems
to be lean always on the top even if i have100% ve added up in the chip, my
WOT AFR has to be well below any real number to even come close to equaling
12.7:1

this is perhaps my greatest dilemma, im about to just put it up at 134 and
be donewith messing with it.. andjustmake therest of the adjustments in the
main fuel and secondary fuel, that promises to be a PITA though...  I dont
even have a real good idea where to set my fuel pressure. The 65 lb'ers in
there flow around 90 lbs at 19 psi, according to some ofthe calculations on
the net thats good for  300 hp,  perhaps my motor is capable of more.. This
is another thing i have to decide on. just find a fuel pressure and leave it
there and then work on the chip.. 

I still know squat about this and any advice would be welcome.. it just
seems like my tbi wont ever pull as hard as that carb did on the top it was
literally like a 75 hp difference... but i just cant go carb, the low end
sucked which I attribute to a weak vacuum signal though the carb guys say
tuning.. either way i want to make this work with the tbi, its my calling card

any tips on setting up bpw and injector flow rates etc etc?

Id appreciate it

Pablo

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