I just turned 15k mi over the weekend. It is probably a coincedence, but it seems that this thing has all of a sudden unleashed itself. Throttle response is better than it has ever been. My son tried the no lift shift on a back road and the thing stood up and went like it never did before. Spins rubber at will in at least 3 gears. Boost pressure, something that I don't worry about too much was neverthess 23PSI+ when I dared glance at the guage. I have had ambient environmental conditions like this in the past, post Stage install, but the car has never responded as well as it has recently.

Anyone experience something like this at a specific mileage interval? I sure hope that it's not temporary.

 

I went threw the same bonus, At about 20,000 miles mine started running better than ever, And at 42,000 it has'nt changed.

 

My cars been through a few tunes since 4500mi and now is coming up on 30k still running strong lol.

 

I also noticed a big jump in responce around this mile marker.I also have an SS. Our first HHR was an lt and I noticed it also grew a pair after some miles.

 

Funny, Kinda like a creeper.

 

It's most likely the engine being broken in fully. All/most cars run faster/better at 40K miles than at 5K miles since the motor's broken in and all the tolerances are "set" in the block so to speak. I'm at 18.2K myself and there are days when I step on it and my lil' SS leaves me wide-eyed and hangin on for dear life lol.

Later
Allex

 

Might it be them changing off the winter formula for gasoline?

 

x2. I'm guessing this has something to do with it.