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



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

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