[Guest]

Placed dual exhaust system in my 69 Mach 1, it sounds great but it seems upon deceleration (like coming to a stop) a vibration occurs underneath the car, any ideas??? Thanx Joe

 

[Woodchuck]

Sounds like you've got one of the pipes running to close to the chassis. When decellerating, the flex in the motor and tranny mounts is twisting the engine, picking it up on the passenger side (i think) and reducing the clearance on the RH pipes. I'd check there first.

'66 A-code Fastback (therapy)
'89 Town Car (SWMBO D'driver)
'87 Caprice (as req'd by Hagerty)

 

[camachinist]

Try running the car up to 30 mph in first gear and decelerating without the brakes....

What do you hear?

Do the same thing except neutral the car and coast to a stop (Ok, you can stop for pedestrians *G*)....any difference?

I agree it might be a clearance problem....

Pat
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