Fuel Issue 09 Mustang GT whipple supercharger

[TunedbyPRD]

I am having a bucking and surging issue with little throttle to slight throttle. The car goes from 14.8 to 17.5 AFR bucks then drops back down to 14 and lower. How can I fix this instant throttle response issue? It feels like there is about a second of delay before the injectors dump enough fuel to correct the afr. Under WOT the car hauls and there are no issues with the AFR. It will also do it when you are cruising and hit the car real quick

[Blown383]

Can you post the tune and log?

[TunedbyPRD]

here is the tune. I don't have wideband logging thru hp tuners. car has a wideband and dyno has one. so I didn't log it with mpvi



The car makes good clean power. smooth graph. made 456whp/499/wtq on a dynocom dyno

[SultanHassanMasTuning]

why is your throttle angle 88?

MAX throttle limits i would put something like 900 and forget it

depeding on your throttle body. but i believe your issue is because you made adjustments to predict and no effective


your whole tune is not right.

[Blown383]

What are the mods to the car? Injectors, TB, exhaust, fuel pumps?

[BlownGTvert]

What are the mods to the car? Injectors, TB, exhaust, fuel pumps?

Knowing the information that Blown asked above will be helpful in addition to the MAF details. Are you certain the MAF table and injector information is correct in the tune?

[SultanHassanMasTuning]

i think the guy slapped on a supercharger and upgraded nothing else.

[TunedbyPRD]

bbk long tube headers, off road x pipe, 34lb injectors.. MAF tables should be correct. he has a 95mm intake tube now instead of the 83mm that is stock. It has the Americanmuscle.com whipple supercharger kit. It has the 12lb pulley on it. and has the upgraded fuel pump

[TunedbyPRD]

Also has hot rod cams

[BlownGTvert]

Both the erratic idle and surging can be directly related to the MAF transfer function. The surging is usually a lean area on the MAF curve for that voltage. I wouldn't assume that the MAF transfer is correct. if the intake tube size and cams are changed this will impact the air flow in the MAF table. This needs to be calibrated and correct as a step 1. Then confirm you have the correct injector data in Engine>General>injectors. You'll spend a lot of time chasing driveability issues if the MAF table and injector data isn't spot on. Report back once you are 100% certain these are correct.

[Blown383]

Just glancing at the tune, I can see that you need to rescale the axis' on the various tables to account for boost. You also need to dial in your Load w/ Failed MAF tables as those are key to driveability and transient response. Odds are that due to your fuel pump upgrade, the voltage table is incorrect, causing fuel pressure to vary greatly as well.

[TunedbyPRD]

ok. Thanks for the help. I will check those tables and keep the thread posted. Any ford shortcuts that could be helpful with this. I am relatively new to ford tuning