So a few months ago a cement truck backed up into my Mini, after having them pay to fix my car, I decided finally to pop in the pulley while it was getting fixed. I got my car back today and the first thing I noticed was a slight "ping" sound when I start my car and the burble from my exhast (borla) sounds quieter. It also seems I have to rev it up a bit higher before I can hear it.

Is this normal? Maybe its because my car hasnt been driven regularly for nearly a month and its sad? I don't know, can someone explain this?

Thanks.

Edit: The ping sound is coming from the engine by the way :P and its more of a "da-dink" sound...

 

I'm no mechanic or expert, but I have a borla also. It's the race or aggresive type also. I've noticed it does seem quieter if it's cold or hasn't been run in a while. I also have a pully which didn't seem to make a difference with exhaust noise. I had a software upgrade along with the pully, the shark injector. Maybe that's what the pinging is.
Not sure though. Just thought I'd chime in with my experience

 

The ping sound may be the metal expanding as its getting hot.

Dunno why the burble would get quieter. Are you carrying more stuff in your boot? It may be covering or insulating the sound from getting to your ears.

 

Are you running the stock (heat range) plugs? It's recommended to go 1 step colder in the heat range with the pulley upgrade to avoid the pinging, or detonation. Also-are you running premium fuel? This can also lead to the "ping". Hope this helps.

 

Colder plugs are to prevent pre-ignition. That certianly isn't an issue on start up or anything but high load driving.

 

Now that I think about it, I do remember being recommended colder plugs, which ones specificly ones I should look at? And yes, I do fill up with premium only.

 

Plugs - I've been happy with the Denso IK22 (colder set).

 

I had a Borla system on my 02 MC and it got quieter over time.

 

Hrmm thats interesting...why do you think it does that? I like the loud pops :D

 

I'll pick up a set of those...anyone have a link on how to install them? Any precautions I should take?

 

I have the Denso IK22's as well. I got them here
http://cgi.ebay.com/ebaymotors/4-DEN...9998QQtcZphoto

Best price I could find and had them in two days

 

I just picked some up from there Thanks!