I have an SXT with about 2,100 miles on it now. I have noticed it feels faster and faster the more miles I put on it. I use regular 87 octane. I am wondering if these cars don't "loosen up" over time. Anyone else notice?

 

Of course cars get quicker ( and better mileage) as they put on some miles.

That helps to get rid of friction, which gives you more power.

My 63' Plym with 426 Max Wedge came "clearanced" from the factory, that is to say that they built the engine with "looser" clearances. My engine was the 415HP one that had 11:1 compression, the 425HP engine came with 12.5:1 compression, on the latter one, you could hear the pistons "rattle" in the bores until the engine warmed up.

Those cars were beasts to drive on the street, especially in a Chicago winter.
I ended up buying a 2nd car for work.

Bob

 

Well, as far as modern, computerized cars go, I would just be surprised if they loosen up that much. But I definitely notice mine is quicker now than when I bought it (the weather has not changed here). With a lot of modern cars now you don't even have to go through a break-in period, correct?

 

I entered this in another string, but thought I stick it in here too, it's a subject I'm right interested in, since my Black Hemi won't be here for what seems like forever

this guy --> break_in_secrets seems to have something, I wonder if it's real?

Any opinions from those who have actual 'inside-the-engine' experience?

Mike

 

VERY interesting

 

There is something to what that guy says... I wish he didn't sound so damn crazy sayin it.

This subject has been spoken about a lot with regard to the RT's and the computer requiring a "break in" as much / more than the engine. Mayhap the same is true of the SXTs. I can say I've noticed the same, though I don't get too much time to appreciate it (have to drive in a calm collected manner when the boss is about).

 

I saw on a post in dodgemagnum.net that the engine will wake up past 7000 miles excatly and will make more power and have better fuel economy.
It sounds like B.S. to me, unless the PCM was programmed to change some parameters at 7000 miles, but according to the forum at dodgemagnum.net more than a few people have experienced that power increase past 7000 miles, go figure??????????

 

I just put this in another thread. So far my number has been 3-4000 miles. Supposedly built into the ECM to keep from us blowing up new engines. Mine feels like its got 100 more hp than it did when i picked it up. 4000 miles on it now and it lays a lot of rubber that was barely a squeek new.