Like these guys said, about the only way to get more out of the 235 is with head work. You can gain some with an 848 head, compression is a little higher. A good port and polish will help, along with milling. You didn't mention your cam. An upgrade there will open up the top end. Contact Patrick's (in the links page), and don't be afraid to go with an aggressive cam. Other than that you will need more cubic inches.
Momma always told me to stay away from Hastings, thats where they sent all the crazy people.
She grew up in Burwell.
