Loud Drone, After Replacing Old A9p Ecu

I just got my 92 gt from a kid that had put in a rebuilt 5.0 only had 34k incl cam, holley annihilator distributor, BBK headers, Flowmaster h-pipe, Performance plus 75mm tb & spacer, replaced iac, egr, wiring, deleted fuse box in the bay, new maf sensor, spark plug wires, & Jet Performance chip on the A9p ecu. Always ran boggy, but strong. Said when he put the motor in, the OD stopped working. That chip ended up frying the motherboard & I finally found a ecu but it's the c3w and now there's a drone that's been getting increasingly louder as time progresses. Everyone says I'm just freaking out, but IK what my car should & should not sound like, especially going 55mph & can't hear the radio. Also I can feel od grab but slips back out, any help would be very useful

Noobz347 said:

My suggestion would be to ditch the "jet chip" and burn it with fire.

THEN, if it doesn't run well, make yourself an appointment for a real tune on a real dyno.

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Oh yeah, we threw that chip away made sure it was gotten rid of. And that kid did mention the only he failed to do was take it in to get a tune

Gearbanger 101 said:

The drone is from the Flowmasters and O/R H-pipe. Swap them out for a straight through style muffler like Borla, Magnaflow, Dynomax, etc and your interior drone will be GREATLY reduced. Weld a set of cats into that H-pipe and it'll get better still.

And yeah.....off the shelf chips are poop. Have it custom tuned, at a reputable shop and don't look back.

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Yea that's what I was also thinking . I got under it at my uncles tire shop & you could tell he ran it with uncapped headers for a while then put the flowmasters on, which have a lot of suet in them but look fairly new, still don't like them... MagnaFlow I prefer