Metallic rattle sound after LTs.
09-16-2015, 08:37 PM
#1
Metallic rattle sound after LTs. Yo.
I recently did Poly MM/Trans Mount and Speed Engineering LTs and ORY to the stock catback. The headers and Y have perfect clearance. Nothing touching floorboards or none of that. Around 3,000RPM I'll hear an awful metallic rattling sound for a second or two, or really any time I'm heavy under load like say 5th gear, 40MPH and plant it.
I'm thinking:
A: This sites general description of rasp. Although rasp sounds bad (or decent on exotics/Vettes), this sounds more severe than rasp.
B: Bad Y pipe merge. Exhaust smashing together at a certain frequency.
C: Muffler/I Pipe contacting or buzzing the gas tank heat shield. It's not touching the shield at rest, but its an ant's *** away from it and I could see it getting some flex under load or communicating some sonic resonance to it.
Only curious as soon I will be converting the SE ORY into a 2.5'' over axle TD setup. Just wondering if this is a common thing on these 4GFs with ORY setups. Rasp seems to be common, but this is much more metallic sounding.
FWIW, it sounds like pure domestic ricer garbage and I hope there isn't a bunch of kids with cheap F bodies that are cruising around to this racket thinking it sounds cool.
I recently did Poly MM/Trans Mount and Speed Engineering LTs and ORY to the stock catback. The headers and Y have perfect clearance. Nothing touching floorboards or none of that. Around 3,000RPM I'll hear an awful metallic rattling sound for a second or two, or really any time I'm heavy under load like say 5th gear, 40MPH and plant it.
I'm thinking:
A: This sites general description of rasp. Although rasp sounds bad (or decent on exotics/Vettes), this sounds more severe than rasp.
B: Bad Y pipe merge. Exhaust smashing together at a certain frequency.
C: Muffler/I Pipe contacting or buzzing the gas tank heat shield. It's not touching the shield at rest, but its an ant's *** away from it and I could see it getting some flex under load or communicating some sonic resonance to it.
Only curious as soon I will be converting the SE ORY into a 2.5'' over axle TD setup. Just wondering if this is a common thing on these 4GFs with ORY setups. Rasp seems to be common, but this is much more metallic sounding.
FWIW, it sounds like pure domestic ricer garbage and I hope there isn't a bunch of kids with cheap F bodies that are cruising around to this racket thinking it sounds cool.
09-18-2015, 09:40 AM
#5
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probably not your issue but i had a spot on my catback near the muffler where 2 pipes were touching and causing a strange noise, a simple small weld fixed. the big noise i had turned out to be my torque arm rubbing my drive shaft safety loop. good luck!
09-19-2015, 11:30 AM
#6
It was the fuel tank heat shield. Took it out and it cleaned up the sound. It still has a little mechanical rasp to it from the Y merge, but the terrible buzzing sound is gone.
....and there was much rejoicing.
....and there was much rejoicing.