So I had my first rx-8 track event last week. The car preformed fine no issues there.
On the way back immediately started to notice that I was getting great gas mileage. By the time I got home (4 hour drive) I was able to get 300 miles out of the tank which is about 20 mpg. Usually I get about 16mpg in highway driving.

Not that I'm complaining, but anyone know why this happened? I redline the car regularly, so carbon buildup shouldn't be an issue.

 

Tailwind, tire pressure, 18 wheeler and Suburban drafting?

 

running it hard on a track or dyno is different than on the street.

 

The drive home sounds like the street to me

 

You miss the point. Driving the car hard on the dyno or track is what is different. Driving it hard on the street usually doesn't compare, which is why the car feels a lot better after.

 

What mysql said.
Tracking the car really lets the engine perform better since you are able to burn a lot of residues and this cleans up the engine a lot.
You also work through various load levels

 

I thought we were talking MGP's here?

Edit: MySQL didn't say anything about carbon so i was confused what he was getting at...

 

I have noticed this every time I do a track event. I have gotten 25 mpg driving home from the track. after a couple of tanks, it settles back to normal fuel consumption. I am guessing it has something to do with the ecu running in open loop on the track and then resetting to closed loop maps on the drive home. Also, track events do a good job of cleaning out the engine of carbon deposits.

John

 

Many have also reported an improvement in MPG as the cars engine wears in or runs in with a little age??

 

My First track event, my car had 600 miles on it. My final break in miles were on the way to the track.

 

Mine has about 5000 miles on it now and it does feel like it's running a bit better now then when it was brand new.

also the engine doesn't pop as much at cold startup, which leads me to believe that there may have been carbon buildup on the spark plugs