Who set timing and where is it at, has it been verified? cehck timing, plugs then compression and leakdown test. Maybe re-lash vaves. I just did almost identical build for a customer, 27 fountain, hp 500 efi, ran 74 speedo most time loaded, 76 speedo running light, hurt motor slightly and lost ring seal. Boat would barely run 72 speedo when he put it away, we pulled motor, Bob Madera spec'd a cam and springs, bored it .030 to 4.500, had heads bowl blended, monoblade throttle body and he's now running 79 speedo w 26 pitch LH at 5600. Runs 78 speedo with my rh labbed and cupped 26 bravo at 5500 in comparison. I think his speedo reads 2 or 3 mph fast too but in comparison, fwiw, Smitty

I brought my boat back to the shop today.He said he was going to do a leak down test and then a water test,with a fuel pressure gauge hooked up to see if its getting enough fuel.I put my 24 pitch hydro on also to see if that helps.Hopefully i should know more by tomorrow afternoon.Thanks for all the input!!

Smitty,The shop set the timing at 34 and will check it again before and after they do a water test tomorrow.

I have never heard of cam motion . On many marine apps the hp500 cam is on the fringe unless you go stroker and or tubular. Or grind a custom from a marine guru who has memorized stock cam specs

I thought Cam Motion was the company that guys like Bob M use to grind their custom spec'd cams. Could be wrong though - need to walk out and look at the box in my garage.

What do you mean on the fringe ?

Not a guru, but I have stock cams and many aftermarket cams memorized. Been doing this since my 1st Crower catalog u=in my early teens. Because of which I can never remember a family member's bday or anniversary. Too many importnat #'s in my head. Hah !

edit in: The descriptions next to each 'Beast' cam made me addicted to cams. Words like 'brutal acceleration' chnged my life. LOL.

let me save you a trip.CORRECT.

Kip Fabre of Cam Motion is known to be a genius with camshaft design. He has done some awesome things in the LSX world. He also grinds custom spec cams from other designers so just because it comes in a Cam Motion box does not necessarily mean it is a Cam Motion designed cam.

Any luck finding out your issue? Did u try the original prop?