95 F355 sounds different after service...

1. Did you re-time the cams?
2. Did you check the status of the exhaust headers?
3. Did you tighten all exhaust nuts bolts tightly?

 

+355 on that.

Is there any loss of power?

Have you inspected the cats?

 

My internet mechanic expertise would point me toward a broken exhaust bracket/clamp around the cats/muffler area....

 

cam timing

 

Make sure your bypass valve is installed properly (not backwards and no leaks in fittings). I had this issue when the shop installed it backwards and another time when it was not properly mated on the Y-pipe side.

 

How exactly did you re-torque the cam bolts?
Did you replace the timing belts?

 

Did he take the engine out or is he just talking about the cam cover bolts (I guess they'd be nuts not bolts)?

 

Then the sound difference is all in your head.

 

As mentioned by PeteyP, a loose exhaust interface would create a sound change ....... also make sure no vent hoses were damaged, creating a crankcase leak .... sometimes old hoses do not hold up well if moved or reseated ........ or finally what GerryD said: VVV

 

The service that was done does obviously not affect the timing, nor the manifolds.
So I would say that the service was not the reason for a different sound.
Did you check for loose fibers (hairs...) in the compartiment (manifold problem that coincidentally worsened at the same time?)
Does it sounds different, when you stand on the right side of the car, compared to the left? Any strange smells?

 

Try smoking it to see if any leaks just happened to occur in any of the exhaust joints and in the meantime, you will see if the headers are OK or not.

 

+1 ... I had a big sound change happen when I had some headers installed by a friend (sounded deeper and boomy) ..... it turned out to be loose flange bolts at the y-pipe interface(s) ...

 

Ferrari .....
If you start listening (to close) for strange noises, you will start hearing them

 

If it sounds deeper then normal, I would suspect a manifold has burned through. Figure out the problem before you drive around with it. A burned manifold can cause some serious cylinder issues.

If you have a smoke machine available, smoke the manifold and look for leakage escaping the shielding around the upper and lower test ports.

 

maybe you had a cold, and were not hearing well?

 

yes. You need to let the car idle for 10 minutes right after start up (with the battery cut off switch previously used) so that the car can learn its running parameters.

 

After a disconnect you are supposed to start the car w/o touching the throttle and let it idle for 10 minutes to learn the adaptive setting. If you hit the throttle during the idle period you mess things up.