Wobble

are you sure you have #1 plug wire? 50degrees of timing will cost power and most likely engine.

rob vanharten

I double checked both motors because I couldn't believe my eyes!!! I am picking up a new timing light tomorrow to verify. I have to believe this much advance was costy me hp and speed....? Thankful at this point I haven't lost a motor. Not sure how this is possible if they really are advancing that much.

articfriends

iTrader: (1)

Rob, I just bought a set of 30 labbed merc 4 blades that woerk well on my v hull, pm me on FB or give me a call if you still have my ph number and want to borrow them just to try out, Smitty

JRider

iTrader: (1)

[ATTACH=CONFIG]545488[/ATTACH]

I was interested in this boat and found this pic on my phone yesterday. Two of these hanging down to be costing him speed, that is the most piss poor installation of a pickup that I have ever seen. I had a text conversation with Rob last night and made him aware of them. On a non innercooled or NA motor with bravo type drive I see no need for them. Sucks he has 2 holes in the bottom but eliminating those is some cheap speed.

rob vanharten

Very appreciative of this information!! As discussed via text yesterday, I was also alarmed at how far down these water pickup's are below the bottom of the boat. Last night I took some additional pics and took some measurements. They are 1" 5'8's below the running surface, and could be the cause of some major top speed scrubbing. The boat does have water pressure pop off valve's in place so to high a water pressure is not a concern. But the thought is to cut these down so the leading edge is flush with the bottom of the boat and then angle cut them so the rearward edge is sticking down maybe a quarter inch? How much speed was I loosing? Remember one of these on each side of the boat. And do my thoughts on how to cut them sound correct?

rob vanharten

Thank you for the offer Smitty!! I am going to try and figure out this timing thing, and the water pick up situation, and then see where we are at before I go changing anymore of my setup. I have determined I have 1.36 drives, and the props I have should be really close if I can get the rest of the boat dialed in. Smitty could 50 degrees of advanced timing be slowing me down? I realize I am lucking the motors are still in one piece, but did it cost me power up top???

JRider

iTrader: (1)

The ones I just took out of my friends 28 were aluminum, they would have been easy to cut down. The ones on your boat look like stainless, not sure how you would cut those down without taking them out.

Wobble

This would be my first choice, the repair should be near invisible if done right. Plus you no longer have the worry of 2 holes in the hull that could sink your boat in a hurry if a fitting fails. Not that outdrives are perfect but a maintained one rarely leads to a sinking.

Cat & Mice

Yeah those pickups are super long, for sure robbing you of speed.

I had the same style pickups on my 28. Mine were flush to the hull in the front and about .5" in the rear. had plenty of water pressure.

I would think a cut off wheel would be able to get them trimmed down enough without taking them out.

MP

articfriends

iTrader: (1)

When we dynoed my 540 boat motor with blower belt off, my 600hp Pontiac car motor and several circle track we found that there was a sweet spot where motor made peak hp, then there would be a spot where it made same hp about 2 degrees higher but was on edge of detonation or simply no gain, then we would go 2 more degrees and find power decaying 10 to 20 hp. On the pontiac we did a tune for scca racing where we pulled 10 degrees of timing and it loses 120 hp. IF your motors like 36 total at wot lets say, at 50 they should be down well over 100 hp , that number is suspect as it should have detonated itself apart by now. I would do a leakdown test as the rings would be broken or soft now IF it was detonating alot aside from lifting a head gasket or burning holes in pistons which you would know