Im going CRAZY, WOT tuning is being a bastard! Running out offuel

[Len sabatine]

At 01:43 AM 5/25/00 -0400, you wrote:
>Something is definately not right here
>
>Heres the breakdown of my day
>
>
>I start tuning WOT this morning, friend (or shall i say carbureted arch
>nemesis) comes by, first chip it runs very strong.. lean past  4200 but very
>strong nonetheless,  he thinks  i might give him a run finally... he leaves
>afterwards.
>So, I go into my AFR- WOT table.. drop it down some at 4800
>Go for a spin again.. runs much better.. still lean a bit on top
>Repeat step two
>Go for spin again, seems like maybe (this is a shot inthe dark)  perhaps my
>part throttle isnt as good as i thought, on therich side, and the ecm is
>leaning me out across the board
>Ok, ill just keep richening it up till its beyond the scope of adjustment i
>figure (yeah im real half assed about things, i just want it to be fast at
>wot at this point)
>Repeat step two.. several times
>repeat thepart about me going lean several times.. yet getting worse
>andworse each time... down to about 3800 rpms its pretty much done.
>Ok, time to go crazy, so i start making big changes in the AFR and FL2 just
>to make it  bird killing, rear bumper blackening, plug fouling rich (id
>rather work down than up)
>ok, it only makes itBARELY better than what it was
>at this point, i think a geo metro can beat me
>desperate times call for desperate measures so i repeat the bird killing,
>plug fouling step
>a teeensy itty bitty bit better if at all
>at thispoint imdown to an AFR of 2 at4800 rpm
>i started outat like 11 andit ran much better yet asthe day progressed it
>seemed to just get leaner andleaner. Im starting to correlate it with heat..
>it seemed the harder and more i ran the car the leaner it got.
>Ok, the pump is new, rated at 40 psi, and42 gph
>The injectors are stock 305 TBI injectors, externally regulated to 50 psi
>the motor is a 309.9 ci SBC, 214/224 .474.498, ported andpolished #416
>heads, edelbrock torker II single plane manifold.. blah blah blah
>as a very conservative guesstimate,  300hp
>thats definately not happening at this point
>im thinking its 1 of three things
>My injectors just cant take it, im running them at too great of a duty cycle
>and they dont like me
>My fuel pump doesnt like 50 psi as much as i thought it would though id
>figure ifanything, pressure would drop, and thatslack could be taken up by
>just making the top end crazy rich in the chip to where itwouldnt run lean
>at say..  30 psi(i know thats not the right way of doing things but im just
>trying to eliminate the pump as the culprate here)
>or, im really really rich at part throttle (im not) and the puter is
>learning to lean everything down, sorta like the return road problem the GN
>guys have
>I could have tested the last one I suppose but instead i just got angry at
>thecar and kept throwing more fuel at it hoping it would go away. It didnt.
>Any ideas guys?
>at this point the darkside (carburetion) is looking very tempting.. tell me
>some good news
>thanks
>
>Pablo
>       Question, How much Fuel Pressure are you Using @ stock GM TBI 
> Injectors ?

   Len

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