MPG 3.8L series II vs series III

[jdcowboy]

So I have a question I am hoping someone has some insights on. I have a 98 GTP and an 06 GTP. The 98 has the series II engine and I can pretty consistently avg 30 mpg on the highway (if I limit the super charger use). I have been disappointed in the 06 with the series III engine as I cant seem to get more than 26 MPG. Anyone know what the difference is? What can I change on the 06 to get it on par witht the 98?
Also I am curious to hear what kind of mileage yall are getting with your cars.
Thanks
Tex

 

[Bio248]

06 is n/a? if so its the 3.29 gears that are making it worse.

 

[matt5112]

3.05's

and check the mpg thread.

 

[tod1d]

check out Fuelly | Share and Compare Your MPG

 

[Fivefingerdeathpunch]

guys, read his sig

he has a 06 GT, so its got a stupercharger.

 

[Bio248]

i didnt remember if that was 06 or 07.