This Odyssey battery turns my 13:1 383 with solid roller valve springs.
It has 900 amps for 5 seconds.
http://shop.odysseybattery.com/p/pc925-a
http://www.jegs.com/i/Odyssey-Batter...PC925/10002/-1
Not sure why Jegs is so expensive. It is available at several places.
$147 --
http://www.amazon.com/Odyssey-PC925-.../dp/B0002ILK72
You will need to use metric bolts for the lugs or purchase the additional posts for post style.