Originally Posted by 454C10
781 heads typically have rotators under the exhaust springs which are normally replaced with thick spacers when stronger springs are used. The springs have a recommended in stalled height so you can used that when you install them. The 268h is a little to big for 7.7:1cr and requires more stall and a 3.55 gear. I would get the 260h if you want to get a kit. What gear, transmission, and stall are you going to use?
My current setup is 305, 29-3200 stall, TH400 and 3.73 moser 12 bolt.
I can always change the converter when I do the bb swap.