:mj:I just bought this 03 cobra and inherited what seemed at first to be a tune issue.
Long story but here goes.
The car had VMP blower w/ 3.3 pulley, "FuelAmp" voltage booster set at constant 16.5v. Stock pumps,maf, and injectors. Car had a street tune done by owner. Car has widband that read 12 ish a/f when pushed in 2nd and 3rd gear. I drove the car from socal to vegas and could barely make it over the hills as the car leaned to 17+ on the widband and fell on its face with ANY boost under part throttle with NO recovery. When I pulled over and tried lower gears again the car ran fine. Major part throttle issues. So.....I bought the following mods prior to going to my tuner thinking it's a tune issue and I had these in mind for the car anyway:
BA3000 maf
3" pulley (17psi)
60# injectors
I installed it all and drove the car lightly to the shop (Shelby in Vegas)
The car went on the dyno and the tuner called and said the car cant be tuned. He tried to give it more fuel in the tune and rail pressure dropped to less than 30 and leaned to 18 so he sent me on my way to get it fixed on my own with no more info than that. I started datalogging with the old tune best I could watching pump duty cycle, voltage, load, frp. I drove it just hard enough to see a/f lean to 16-18 with no pinging, checked the log and saw duty cycle never reached past 20% and frp never dropped lower than 37. I then went ahead and changed the fuel filter and took it to another guy at Dyno Jet Carl is very helpfull) and he checked it and said fuel is good and just needs tune. Problem is I am into Gil at Shelby for money to be credited towards the tune, AND I have a Diablo and Carl uses SCT.
My question is: All I did was replace the filter which was not clogged so what else can I do to check this thing before I find out on the dyno that it STILL cant push enough fuel. Should I shotgun it with new pumps/fpdm/frp sensor? Is there a way I can get a close enough ball park tune to do more datalogging and road tests myself because the delima is the car has the stock injector/ stock maf tune in it now and of course does not run right enouph for and heavy load testing. I will gladly pay someone to just fix it and tune it but I can't seem to find that person. I just want my car to get dialed in. I was thinking put the kit with GT pumps in with the modded fpdm and pprv delete and take to get tuned. What else is left? Or could it possibly be the fuel filter all along? Could it be the fpdm? could it be the frp sensor? My head is spinning and I need someone who knows these quirky returnless systems to fix it. Car has 30k miles and 6k on the filter I just replaced. BTW has new plugs.
ANY help would be greatly apreciated. [email protected]
702-281-6360
Long story but here goes.
The car had VMP blower w/ 3.3 pulley, "FuelAmp" voltage booster set at constant 16.5v. Stock pumps,maf, and injectors. Car had a street tune done by owner. Car has widband that read 12 ish a/f when pushed in 2nd and 3rd gear. I drove the car from socal to vegas and could barely make it over the hills as the car leaned to 17+ on the widband and fell on its face with ANY boost under part throttle with NO recovery. When I pulled over and tried lower gears again the car ran fine. Major part throttle issues. So.....I bought the following mods prior to going to my tuner thinking it's a tune issue and I had these in mind for the car anyway:
BA3000 maf
3" pulley (17psi)
60# injectors
I installed it all and drove the car lightly to the shop (Shelby in Vegas)
The car went on the dyno and the tuner called and said the car cant be tuned. He tried to give it more fuel in the tune and rail pressure dropped to less than 30 and leaned to 18 so he sent me on my way to get it fixed on my own with no more info than that. I started datalogging with the old tune best I could watching pump duty cycle, voltage, load, frp. I drove it just hard enough to see a/f lean to 16-18 with no pinging, checked the log and saw duty cycle never reached past 20% and frp never dropped lower than 37. I then went ahead and changed the fuel filter and took it to another guy at Dyno Jet Carl is very helpfull) and he checked it and said fuel is good and just needs tune. Problem is I am into Gil at Shelby for money to be credited towards the tune, AND I have a Diablo and Carl uses SCT.
My question is: All I did was replace the filter which was not clogged so what else can I do to check this thing before I find out on the dyno that it STILL cant push enough fuel. Should I shotgun it with new pumps/fpdm/frp sensor? Is there a way I can get a close enough ball park tune to do more datalogging and road tests myself because the delima is the car has the stock injector/ stock maf tune in it now and of course does not run right enouph for and heavy load testing. I will gladly pay someone to just fix it and tune it but I can't seem to find that person. I just want my car to get dialed in. I was thinking put the kit with GT pumps in with the modded fpdm and pprv delete and take to get tuned. What else is left? Or could it possibly be the fuel filter all along? Could it be the fpdm? could it be the frp sensor? My head is spinning and I need someone who knows these quirky returnless systems to fix it. Car has 30k miles and 6k on the filter I just replaced. BTW has new plugs.
ANY help would be greatly apreciated. [email protected]
702-281-6360
