Gus. Happy to talk about re-building an AC Engine. There is a certain person in the UK who professes to know what he is talking about but, when it actually comes down to doing it, he falls flat. The best person in my opinion over here is Brian Taylor and I have also received good advice from Robin Woolmer. Brian is currently building a very high spec engine for me but, at the end of the day, you can't fit a quart into a pint pot, despite what some people would have you believe. You could end up spending a fortune without a lot of gain in BHP.