Part Throttle Help 08 GT500

[Z71]

I am having some issues with part throttle driving from around 1600-3000 rpms. Mostly noticeable in second and third gear. Its almost like the throttle body is opening and closing back and forth. In my scan from frame 2823 to 2930 i was in second gear slowly accelerating and she was bucking while accelerating. The tps shows a consistent 19-20% from 1800 to 3500 rpms. Absolute TPS goes up with RPM.

Any ideas?


Upgrades are:

JLT 123mm cai, L&M 66mm throttle body, 2.5" pulley.

Still using 2.24 scanner.

Thanks!
GT500 5.5 LTFT Disabled. Pedal WOT Start.hpt
5.13 part throttle driveability.hpl
gt500.cfg

[Z71]

Or is their anyone that has a configuration for an L&M 66 mm throttle body?

[Rick@RRE]

I've recently jumped into the ford mustang platform and I've encountered the same issue on a 2014 5.0. I can tell you from extensive trial and error it's mostly related to the "predicted throttle angle". This needs to be precisely tuned to sort out the partial throttle bucking.

I hope this helps.

[69b302]

I had a L&M 66 on my 07 GT500 for a while, and the tunes I had for the L&M 66 did not have any adjustments to the Effectve Area, or the feed forward table(predicted throtlle angle in HPT world). I am running the BPS 73MM now, and multiplied the Effective Area by the percentage increase from the stock twin 60 mm. I also change the predicted throttle angle table to reflect the new effective area at throttle angle. I took a quick look at your tune, and not sure on the values you have for the tip-in torque multiplier table.

[Z71]

Thanks for the info. Yeah I never adjusted the tip-in torque multiplier table. Those are stock values. Or at least I hope so anyways. Compared another stock tune file and its the same as mine. I think I fixed the problem. The throttle body I have I purchased from someone else who already had all the electronics hooked up. I swapped them out with my stockers and it runs fine now. Same part numbers and everything so who knows.