I've done several Duratecs on just bodies and the results are very similar to standard Mi16 or GTI6 on bodies. In Ford terms it's a good engine (and the later Zetecs weren't all that bad), but it's not that remarkable if you're used to Peugeots or Hondas. In terms of parts availability, everything you can buy for the Duratec, is available for the EW, rods, pistons, cams, pulleys, cranks, you name it. If you want to take advantage of mass market high quality parts, then none can get close Honda engines. Building a Duratec using low-medium quality components will be very much the same deal as an XU or EW, using the better stuff will be just as expensive. I'm not kidding around about this, on the Duratec we've engine dyno and in car tested just about every available rod, piston, crank, cams, inlet set up, exhaust manifold, head (inc our own, Cosworth and other CNC ones) in 2.0 and 2.3 litre form, even several other builders complete engines! I know what I've seen and felt and I don't think the engine deserves any exceptional credit over the best of the rest, including the EW.
Incedentally, as a nugget that is worth taking heed of, the best results we've seen from a 2 litre Duratec (in terms of overall delivery), have been from the worst performing head on the flow bench (a head we ported according to what we felt was right by eye/measurement and only flow tested after). Which serves to reinforce my belief that flow benches are a distraction in most cases.
Comparisons between the EW and XU are arbitrary unless you can align the specifications enough to be truly objective about it. But as i've said already, a stiffer, more advanced and lighter block design is good for high stress applications, especially improved reliability. The heads are clearly developements of the XU design that I feel overcome the limitations of the XUs; not necessarily for outright peak power or flow bench results, but for making a better engine overall. Playing top trumps with pure numbers isn't what it's about for me; I look to improve the way the power is delivered, how it drives (often a function of how well it maps and that's an important feedback loop) and that helps it to perform well for longer; less worries for me and better value for the users.
That weight quoted is literal, with a race flywheel, inlet, wet sump, no fluids. I'm not sure what the exact weight of comparable XUs are off the top of my head, but if I get the chance I'll weigh them too on the same scales.
The middle bottom 3 bolts on the exhaust manifold are in the same place relative to the exhaust ports as the GTI6/late XU heads, I have a double drilled dyno manifold I use on both, the in car angle will be all wrong!
Perhaps using the Mi16 crank (I haven't tried it), would enable a choice of 50mm BE journal rods from the standard range, to mix and match, you'd have to figure that out for yourself.
Trying to fit an 8v head crosses the mind, for sure, but on a rational level... why bother?! The oil feed is in the right place, coolant holes close enough, but oil drains would need to be external.
Using mildly upgraded factory EWs, will always be limited by the hydraulic followers really, before anything else and I see no reason why it shouldn't be fine with a 7200-7500 limit, unless you use it like an idiot! Beyond that, it's becoming a race engine and like any engine, careful scrutiny of components is sensible (even Honda engines need attention for sustained 8000rpm use if modified).
Edited by Sandy, 18 January 2012 - 07:27 AM.