Results 1 to 2 of 2

Thread: Tuning out raspyness at mid throttle mid rpms?

  1. #1

    Tuning out raspyness at mid throttle mid rpms?

    I have a procharged 2011 3.7L with a smaller pulley, gt500 injectors, and bbk longtubes and x pipe, borla atak exhaust.

    The x pipe was sounding great but i shot the cats into the mufflers and had to do some cat surgery to remove them. Its a bit raspy now but it seems only at mid throttle mid rpms and I feel like its something with my tune.

    Any advice on how to make a loud exhaust less raspy with a tune?

    Ive been trying different transport delays and recalibrating my maf after and it definitely changes a bit but once its out of the transport delay area rpm wise (3k) it gets raspy. Ive considered rescaling my table to 5k and adding more delay but at those rpms itd be shorter if anything once the longtubes start flowing.

    Im thinking with TI-VCT i can maybe adjust the exhaust valve timing at that load range or possibly adjusting timing. It sounds like the valve is opening and popping a little making the raspy sound.

    Under very light throttle it sounds amazing, wide open pulls it screams but loses the rasp which makes me believe i need to make a valve timing change, even if its just in optimum stability or emissions reduction since under good pulls it loses the rasp, i think optimum power mode is dialed.
    Last edited by [email protected]; 1 Week Ago at 07:38 PM.

  2. #2
    Tuner in Training
    Join Date
    Dec 2023
    Location
    Palm City FL
    Posts
    34
    I am not an expert at all . . . actually very much still learning how to tune my raptor, and I only have single overhead cam on my 6.2, but in all my tune variations, i've found that retarding the cam timing seems to reduce the loudness of the exhaust. I can actually make highway drone go away with retarded cam timing . . . but i lose performance which was not the goal.

    Like i said, i'm far from an expert, but that was my experience.
    - Brad
    2014 F150 Raptor
    6.2- 11:1 Compression, Long Tube Headers w/Cats, Volant Cold Air Intake, 180* thermostat.