330hp 454 Merc Dyno Curve

[ECeptor]

Does anyone have a dyno curve (or tabulated data) for a bone stock 330hp 454 Merc? Given a choice, I'd prefer the older Mark IV carburated one.
I'm trying to get my DeskTop Dyno calibrated and need a starting point.

[SmokinLowriderSS]

Bad part is needing a cam. Is likely a stock cam (GM) but which one to be sure of. Here's my 2 best guesses, out of my Hotrodding BB Chevy's book.
Part # Uses Lift (Int/Exh) Timing Duration
3883986 - Hi-lift Hyd L-68/LS-5 etc- .461/.480" 20-68/74-20 268/274
6272989 - Hi-perf Hyd/street&marine-.500/.500" 56-120/107-65 356/352
Duration is @ .008" lift off the seat so set as seat-to-seat timing.
The first one is the one that came out of my 454. The lifts checked out but I have ne way to measure the duration.
Good luck.

[ECeptor]

I think I have the cam specs from the Dennis Moore "Big Block Chevy Marine Performance" book.
It shows a GM 3904359 or Merc 431-4734 with 213/217° @ 0.050, 0.460/0.480" int/exh lift, 110ATDC intake, 118 BTDC exhaust and 114° separation.
Smokin', I think your help has me dead on with the DTDyno I just hoped someone somewhere actually had a dyno curve on a 330hp Merc so I could validate my 2,000-4,000 rpm numbers.

[SmokinLowriderSS]

I was pulling info out of my "How To Hotrod Big Block Chevy's" book by HP books. 1986 edition. haha Sure looks like almost identical cam really. My specs are "seat to seat" specs and yours are .050" to .050" I have no lobe sep listing. They sure are close/similar. Yea, I'd like to see validation as well. there were NO numbers on my cam, none at all.
Cams sure have come a long ways. My book shows factory mechanical cams with less lift and a lot more duration than mine, roller cams, and I'm on hydraulic non-roller. :D Good example is the (pretty much) race-car cam that went in the 425HP L88 427's. .540"/.560" lift (in/ex) 326*/334* durations. I'm running .565" and 280*.