96 Saleen Power Loss At 4psi

[Matt88]

View attachment 73031

my 96 4.6l sohc is lossing power badly at 4psi, my car typically kicks 11psi at 6,000rpm no problem,but after my battery died this is what is left, could i have lost my prodynotune by livernois. or is my vortech v-1 s-strim blower going bad, the car runs great until i 4psi then it done its like im in mud.
if i need to tune it what is the preferred sct tunner?
i could be way off base on all of this im looking for help and all advice is welcome
thanks in advance
at least my 88gt is running well,its fun, but not the same as my saleen
Matt88

 

[trinity_gt]

You sure you're not leaning out when the boost begins to build?

How are you doing the fuel? Is it just an FMU or ...?

 

[Matt88]

You sure you're not leaning out when the boost begins to build?

How are you doing the fuel? Is it just an FMU or ...?

The boost build from -20psi to just below +4psi is very strong, but when i reach that 4psi mark my car starts to fluter and losses power,wich happens to be my main powerband between 4psi and 11psi.. My saleen was tuned by livernois out of D-town. anyways i had not driven it much like normal and my battery died to the point of having a dead cell! the battery was a motorcraft. do u know if this could have erased my dyno tune or possibly the hole computer.
Also im running a FM unit with 30lbs injectors, i have new plugs wires and battery. my air fuel ratio remains consistant with out change.
I can run the r's all the way up to 6grand in every gear and it pulls as it always has,but he minute i look for my big power she fluters,im sick and lost over this!
i hope this addition info helps
-Matt88

 

[trinity_gt]

What does the AFR read when it begins to stumble?

 

[Matt88]

What does the AFR read when it begins to stumble?

14.2

 

[trinity_gt]

That's much too lean. You should be more like 11.5 to 12:1 or so. I suspect you've got a fuel pressure problem. You should verify the vacuum line connection to the FMU and put a pressure gauge on the fuel rail to see what's going on. I'd recommend staying out of boost until you can determine why you're so lean.

 

[Matt88]

That's much too lean. You should be more like 11.5 to 12:1 or so. I suspect you've got a fuel pressure problem. You should verify the vacuum line connection to the FMU and put a pressure gauge on the fuel rail to see what's going on. I'd recommend staying out of boost until you can determine why you're so lean.

i will apply that advice,thanks for ur knowledge, i agree im leaning out getting a bit of white smoke around that problem time almost insurres that. do u think i could have lost my tune and should buy a tunner and retune?
my t-rex fuel pump is runnining steady at 60, could i have a possible bad injector?

 

[Matt88]

i will apply that advice,thanks for ur knowledge, i agree im leaning out getting a bit of white smoke around that problem time almost insurres that. do u think i could have lost my tune and should buy a tunner and retune?
my t-rex fuel pump is runnining steady at 60, could i have a possible bad injector?

im not driving the car until its corrected and it is killing me,im sure u can appreciate that.
thanks again please continue with ur thoughts.

 

[2002BLGT]

Sounds like fuel pressure issue to me , dead battery does not do anything to the tune