Tom, I'm running the classic 425 Impco with a model E vaporizor and an electric lockoff hooked to an oil pressure switch. I could have gotten away with a 225, but it would have run out of breath on top. I will probably have a little harder time stabilizing the idle, but hopefully the rhoads lifters will help.
STS doesn't wrap them, but a lot of guys on the LS forums do to help with spool with a bigger turbo. Although your pipes don't last as long when they're wrapped. I'm kind of on the fence about the wrap right now.
