Okay, so I now have over 5000 miles on my car and to me it seems like the engine has grown louder, is it just my wishful thinking? Have you guys noticed any difference?

 

Yeah mine too...and it seems to rev harder and faster now!

 

Going on 3500...yes engine is louder (could be because I don't turn up the shaker much anymore) and more power for sure.

I also use premium for that extra pickup [sm=icon_rock.gif] [sm=icon_rock.gif] [sm=icon_rock.gif]

 

my car is at about 4 grand miles...i usually have the shaker 1k on so i dont always hear the engine but id have to listen

 

The compuer does learn how you drive and adjust it's programming accordingly (or so I'm told)

That might have something to do with it.

Some mufflers also get louder with time (I'm not sure if the stock one does or not).

 

I have 3,800 on mine and have not noticed a difference on the engine sound. Maybe my new exhaust covers up the change or it is a GT related thing. I thought using high octane gas without a new tune was bad for the engine. No issues on your chrisc65?

 

No issues...I don't think it's "bad"...just not required. The manual says it requires 87 octane. Try the 91...you see a huge boost in power.

 

87 octane is fine with me...i only really drive it hard on weekends...weekdays it spends 90% of its time in the parking garage at work..which is good for me cause it protects the paint and keeps it clean during winter months

 

Same here except that in California, "winter" doesn't mean the same thing to us (no salt on the roads.) I use the 87.

I don't think I've noticed a louder engine, but it's difficult for me to compare the sound I'm hearing today with the sound I was hearing 3 months ago.

 

Where'd you get that idea? You won't see any boost in power unless the PCM is tuned to take advantage of the extra octane.