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