I was just over on the Wallace Racing calcs and plugged some numbers into the calculator, since I have been told these MW Victors have lazy ports( poor volumetric efficiency) and my Mach Index is .66. Wallace says anything over .50 requires a late intake closing point of 60 to 90* ABDC. My cam has a 61* closing point. Anyone up on this Mach Index stuff? Any truth to it? I could use some schooling on this. Thanks

Most of the cams I have seen for the Mopars tend to have more exhaust duration than intake duration....Seems to lend some truth to what your asking, at least on the exhaust side.

If I had a good set of heads on my Duster, I can tell you that thing would fly....Mine only flow 325cfm......6.12 ET last week at 112mph.....We have a set of CNC'd 325 Big EZ heads down at the shop I may decide I need to own....Although the only shop with a way to flow them closed up last year....

My unsolicited ... don't bother going down that path. You'll end up chasing your own tail trying to use the outputs from some of the "calculators" on that site. Example: I put dead-nuts accurate data into the "DSCR calculator" and the cranking pressure output was 30+ psi lower than my results for the real engine from which I took the data.

I'm thinking about spending the money on the performance trend program. I have been told its very accurate by someone on here that uses it.
My cranking compression is 175-180, I think it would be beneficial if it where closer to 200. Not sure something like that would show on a time slip, but every little bit counts IMO.

I own a number of engine simulation programs ranging from early Desktop Dyno to the top-of-the-line Engine Analyzer Pro. EA Pro gave me sort-of-accurate results AFTER I gamed a bunch of the parameters to try and get it to replicate actual engine dyno results for known BBM combinations. Plugging in the actual data prior to that gave questionable-at-best results, which is I why I felt the need to jack around w/ the features to try and get more realistic results.

After I had gamed my "sort of accurate" EA Pro baseline, I provided the actual inputs for someone else to run in the latest version (at the time) of Dynomation. Not only were the results very different from each other, neither were that close in terms of outputs & RPMs to the actual data from my engine dyno session(s). The Performance Trends Engine Analyzer programs -- I have (had?) -- showed more realistic TRENDS from certain component spec changes than the Dynomation program did, but weren't necessarily accurate from a predictive standpoint.

I gave up on engine simulation programs after that and consider them all toys, or at least the ones I can afford to purchase. If I ever got the itch to buy another program (NOT likely), I'd look more seriously at the latest PipeMax release (4.?). I have an older 3.9x version which is far less robust in features, but at least provided some usable outputs for what I was doing.

EDIT: This is my "Last Hurrah!" on the subject: If you're a Speed-Talk member and can access the Advanced Engine Tech forum, you might want to read through this: https://www.speed-talk.com/forum/viewtopic.php?f=15&t=49826&hilit=mach

ok, i'll check out the new pipemax 4.0. I was under the understanding the new Trends was quite good. Maybe not. Thanks brad