Lost mph in my mandella whole story

[nathandouglas]

I have posted prior about my boat to understand how to get some mph out of my boat. when i puchased the boat 66 mandella 17'4, 8 percent overdrive gears, i put in a 429 stock ford with tunnel ram and single 850 carb running msd ignition marine. has 8 percent gears and a old stellings 12x15 prop. revved at 5700 on mechanical tach from v drive. going 63 mph gps. i put in a procomp distributor mechanical advance. the pins that held the gear on shaft broke and so no oil pressure bottom end blew a piston and a few rods i will never buy chinese parts again!.took motor apart and cam was almost flat.

Now i have a stock newer 460 . brand new cam is a summit 218/228 at .50 lift. .503/.503 exh lift 114degree. a edelbrock performer intake 750 vacuum secondary. points distributor, didn't put tunnel ram back on. now boat is running guessing didn't gps at 50 at 5500rpm. i was running a 11.5x15 three blade, not my 2 blade stellings 12x15 pitch couldn't even keep up with my uncles 71 schiada flat with stock 350 with three blade prop. but where do you think i lost the mph at.

[boatpoor]

The three blade will slow you down, what was the compression. Timing, maybe a 112 lope center. None of the old cast iron pieces were left in the boat?

[gfinishline]

Isn't "Pro Comp" from down under? Anyway, "218/228", ".503/.503" is pretty small, and on 114. The Performer intake should be the Performer II or Wieand Stealth. Points distibutor? What curve? I have just thrown out a few things and I haven't even seen your boat. The old 429 sounds like it was a good runner and this 460 needs some help. Did your static compression go down?

[nathandouglas]

429 in book said compression was 10.5to1. new motor is 8.5 to 1. distributor is a stock points distributor from auto store. don't know what curve. cast iron pieces like what. should i put tunnel ram back on.

[gfinishline]

Your "2 point drop" in compression can really make a difference. If you are going to stick with the points dist. get it curved to bring in all of the advance around 2500RPMs. Panther Marine offered a number of marinized motors way back. Two of them were based on the 460 Ford. The stock 330 HP motor ran very well, but the "500" was the same motor with a single top tunnel ram on it. It LOST 3% of it's power with the tunnel ram, and knowing that, they offered one year warranties on all of them. Funny how things "look and/or run".