Engine simulators

Anybody using Desktop Dyno or Virtual Engine Dyno 2003? How are they?

I have used Desktop Dyno (an older version - I haven't used the most recent one) and it was fairly easy to use and seemed to be relatively accurate - though a bit optimistic. The version I used assumed alot of the little things - for instance, you couldn't tell it you had forged aluminum pistons or steel pistons - it just assumed something. That kinda thing, but it did have a relatively powerful flow simulator for the heads - but you needed very precise data to input custom heads and you couldn't make a custom block - you could only use the ones they had, which was alot, but I don't think it included the 4.0. At any rate, it was OK - but not perfect. I'd like to see ALOT more options in it before I bothered to buy it.

I'll second that. There are some OK freeware ones out there, but the catch for the average Joe (not saying anybody here is!) is the input data needed is tough. Not things like carb size or valve size, but the stuff like CFM flow through ports, carbs, flow at (x)amount of valve lift, just the snall but important details for a good result that the repair manuals just don't give. I've tried to use some of them for motorcycle engines I build but found them too frustrating. Need concept, but nothing beats a real flow bench and a dyno if you got the $$
Try some of the freeware and see what you think. I can't think of any names right now, I have one on my computer at home still I think. I've got several two stroke versions if yo wanna get weird!

Desktop Dyno 2000 doesn't have the 4.0L but I just chose a Crystler I6 and entered in the 4.0 bore size, crank stroke, comp ratio, cam stats, head stats, etc.... It came out at the HP/TQ ratings my FSM says. I will post links to the files if anyone is intersted. I have one for the HO, RenixII, and a 4.6L AP stroker.