odd TBI problem

[dusterbd13]

i have begun to open track my TBI project. it really does quite well, but im having a problem that i cant figure out. coming out of hard right hand turns, like out of turn 14 onto the front straight at CMP, the thing lays down. just no power, no throttle response, no acceleration. will so it more or less depending on the turn sharpness, and also on left hand turns. will not do it on the street.
as far as eliminating variables, i have tried a new fuel pump and filter, rebuilt the TBI, and tund it up. full tank or empty does not make a difference. does not do it in the rain, only after the track dries out and i can drive it harder. it gets worse the further into the session i get. im stumped on this, to be homest. i left this thing injected so i wouldnt have to worry about these kinds of things.
the vehicke is an 87 s10, five speed, 2.8 TBI. stock 92 ECM, stock PROM, stock motor. the motor has had th EGR removed, the air pump removed, timing bumped to 12 degrees initial, no cat, and 2/25 exhausts. no CEL happens to light, and no backfiring. seems like it is running lean at these points. i have not verified fuel pressure, nor do i belive i can do so safely.
if you have any ideas, let me know.
thanks
Michael

[MonzaRacer]

Actually yess you can, tap into the pressure line with proper fittings(ie compression or flared fittings and run a proper braided steel/teflon lined hose with crimped on ends to a guage, mount guage on cowl or I believe Autometer had a membrane device that fuel pressure line ends at then another filled with no flammable liquid goes to guage.
OR use electric low pressure guage as the TBI is only running 13 psi max.
IF its dropping you may need to do away with stock tbi regualtor if possible and use aftermarket one.
You also may be having computer over heat so maybe a computer case fan blowing on ecm may help, had a dragracer that lived in Phoenix with similar issue, he eventually went Megasquirt.