AFR ?

[mike454]

donf, yes I agree on the difference I didn't like it would only deadhead at 16 psi too.
Im thinking im gonna change the pump anyway, but I don't think thats causing my problem.
while attempting to emulate(been awhile lol) when it ran on the limp in mode it was at 11.5 to 12.0 afr,..so that tells me the fuel is available.

The injectors that are in it are #GM 17111784 which say they fit 90-93 7.4 tbi

No exhaust leaks for sure upstream of my Wideband,the entire exhaust system is new, and I checked it with my hand and ear, while I had it on the lift, it has new manifolds that have an O2 sensor port on both( I guess some models had the sensor there's they make a bung on both manifolds right above the flange...ive had it there on both manifolds and it reads the same there on both sides, as well as in the factory hole where the 1 o2 sensor it has sits, and I checked it with my clamp-on at the tailpipe, and it was basically the same in every spot. ( + - .1 to .2)

Engine is bone stock never had anything done other than what the dealership did under warranty, and the 3-4 sets of manifolds and gaskets over the 65k miles that are on it. and the trucks main issue is the manifolds running sooo hot its always burning donuts because the constant heat of being cherry red and cooling off loosens up even the grade 8 fasteners and new manifolds I put on it 1000 mi ago..

I ran the fuel pressure gauge from where the fuel filter would be(my adapter for tbi takes the place of the filter) and ran it up inside the cab so I can watch it while driving... rock solid steady at 14 normal driving and WOT up to about 80mph,never moved really.
previous owner said fuel pump had been changed but he had no idea with what.
so im gonna change it anyways, but im thinking there's has to be something or some reason for the ecm to be leaning it down...( I don't think its mechanical issue with fuel system, but maybe im missing something?)

I finally figured out how to get the emulator to run and then it got dark on me, but
tomorrow im gonna bump up the fueling while driving and see if the afr will come down and what effect that has on manifold temps.

any insight would be appreciated.
Sorry for the long explanation,just trying to give a little background
mike

[mike454]

ok, I swapped out the pump
I went with the vortec pump,regulated to 14 psi.
definitely much better....afr stays in the low 15's now.
I will do another log, now that I have the emulator up and working( it does allow me to make a change and upload it)
any suggestions where to look to help this pig power wise? I think the mixture not being so lean will take care of the manifolds turning red.
Dave or anyone else that has a sec to look at my log and maybe nudge me in the right direction, kinda new to tuning this way,but i can see its basically the same, just get there in a different matter.
anyone have a good power optimized tune for one of these? that I could compare side by side to see where changes need to be made and how.....
its bone stock,

thanks for the pointer so far

mike