(If images look jagged then click them, the forum shrinks 800x600 images just a tiny bit which makes things jagged looking on my PC.)
compare to the factory flywheel rating (as nicked off Dino's site): '91-'95 XJ: 190hp at 4750rpm, 225lbft at 3950rpm, redline 5250rpm
As you can see its a lot like the factory rated flywheel output. Dino found that the factory numbers may be a tad conservative and my model may be as well, as my exhaust flows are a bit more restrictive (didn't use a flow pipe). The curves look as they should (also from Dino's site):
Keep in mind that's not a symmetrical graph, and it's scrunched together. hp numbers on right torque on left and they are at different levels. If you adjust the scales to the same size or manually plot out the factory curve over the EAP graphs they are damn near identical. Crazy part is I ran that plot, without actually seeing this factory one until I found it on Dino's web page while writing this. Believe it or not there was no tweaking of EAP parameters to get the torque curves so close.
So next post I'll tweak the exhaust flows (flow them with a flow pipe they should be slightly better CFM) and we'll prove out the model (or find inaccuracies) by bolting on virtual 99+ intakes, 63mm bored TB's, borla headers etc.
Now the long part; I got this far without doing anything funny that is not in line with the real engine. The port flows are real world from my bench (and they happen to agree with other flow bench numbers I've seen and that have been posted here) I didn't have to fudge anything. When I get a few more things tweaked, and confirmed. I will put the engine files up for download probably in this thread. Here's some screen caps to give you an idea of how much input there is. Each area has multiple calculators that take measurements and turn them into coefficients or areas, or CFM etc.. Whatever EAP needs. There are area's for rotating mass, valve train weights, angles etc. Here's the short block menu:
This is one of the most simple menus and there are 4 calculators off it it which all can take multiple inputs or measurements.
The cylinder head menu and intake flow sub menu
Okay so big deal I've got a simulated 4.0... but now the fun part, once you have an accurate stock model then we can throw mods at it and get predictions that should be reliably accurate to within a few % assuming I didn't screw the pooch. 1% to 3% at our power levels translates into 2 to 6 hp and torque. So we can throw combos and cams around and see what sticks and what stinks. Or at least we can if we get realistic looking results from known mods to the 4.0. If virtual bolt ons have believable effects on the graphs, then we can move on to virtual strokers, Virtual cam swaps, Custom intakes and even more radical build possibilities. How about 48" long tube headers with an RV cam and a long individual runner fuel injection intake (for max torque).
<- Spock smiley).
