STOCK1SC

Did you notice a power increase after 3,750 miles? I've heard rumors that the stock computer limits the VVT for the first 3,750 miles until the motor is broken in well, I figured it might be BS but you never know. Also heard they make significantly more power below 80 degrees temp but not sure about that either. I've just notice big discrepancies between the 6.4 times, some are 13 flat, some are mid 12's and other's are around 12.8 not sure which is most representative.

USHotRod

I honestly couldn't say since mine hasn't hit that yet. I bought it late last summer and then had to store it for the winter, which is just now starting to melt off.

From all accounts on the Challenger site I'm on, its true. People opened threads stating they felt a surge in horsepower after that milestone. I know my Jeep had it too.

The time discrepancies may just be between the autos and manuals. People arent having much trouble getting an auto in the low 12's. The manuals are struggling a bit, getting about 1/2 second behind on average by the looks of it. Personally I could care a less as the 6 speed is way too much fun.

guionM

Wouldn't dismiss it as BS.

For years, computers on cars have been programed for a break-in period.

All cars perform better after the break-in period. The computer running Chryslers LX cars are (or at least under Daimler, but may still be) a bit more conservative than the norm, and therefore have a more noticable difference after break in.

Not saying they change into Mr Hyde after spending a 1000 miles as Dr Jekyll, but there is a notable difference in how they run and perform.