I think I understand how to measure shaft to pad relation. I level the pad. The only way I know to describe what im calling the pad on my boat is that its the small section that's stepped up at the stern. I'm leveling off of that which is a much different angle than the plane of the main hull. I'm then leveling the outboard using the anti cav plate as a leveling surface. I measure from pad to ground and then centerline of propshaft to ground. If I'm 16" from the pad to ground and 13" at then prop shaft I'm 3" below the pad correct?

Now that im thinking about it I guess the number doesn't matter that much. It's just a reference. Could measure it however so long as you always do it the same way every time.

I guess my question is what is the best process to determine the optimum height. I know that set back, the particular prop, and hull all make it where there's no magic answer. I am no where near that level where i understand lift and prop pitch, etc. and what it does for me. I'm just looking for advice on the general process of finding the sweet spot with my setup. I'm running a hydraulic plate so I have a gauge of engine height, I've got a water pressure gauge as well so I know when im getting to thin.

 

Could measure it however so long as you always do it the same way every time.

Yup, that's a fair statement.  I did mine the same way as you.

 

My advice, move it in 1/4" increments at first, each time testing on the water, until you get it close.  Then move it in 1/8" increments until you find the spot you're happy with - which is subjective.  Yes, moving it only that much can make quite a difference.

 

It will be a balance between speed and handling, and your comfort level.  Everything feels great going straight and on plane., so be sure to make hard turns in each direction at different speeds to get a feel for handling, before and after you make each adjustment. 

You have it easy with a hydraulic jack plate, just play with trim and lift until if feels best and runs the fastest.

 

If you are not familiar with setting one up, Ken Cook has some of the best info already written out so I would start there.  http://www.kencook.net/Setupart.html

 

Thanks guys for the advice and for the links. It's a 201 pro elite. Moves pretty decent for its size but I'm always wanting more speed. Learning to drive it has been a bit more of a learning curve for me than I expected. It drives itself to low 60s. After that it starts getting pretty sensitive to everything I do. Looking forward to getting that last little bit out of it.

As always y'all's help and advice is greatly appreciated.

What size jack plate? I've never seen but one with a 6" jack plate (and I set that one up for a friend), because it seem most people go with at least an eight, and many go with a 10" or more However, a friend of mine that was a Stratos dealer, factory backed by OMC for most of his racing carrier, and owned Stoker boats always told me a 6" was all the setback a 201 needed with an OMC 225. I built his motor that started life off as a Venom 200 and pushed his boat 62 mph with no jack plate just him in it. When I finished with the motor, the setup and a 26" Raker tuned by Bob Lipton. When jetting it with me and him in it, I was 212 at the time and he was 225, it peaked at 81.6 mph gps and egt's bumping 1,250 degrees. Since it was a little cool that day, I went a little larger to give it a cushion and it was running 78.3 at 6,500 rpm and 1,205 degrees egts. On his, we ended up with the prop 2 1/2" below the pad.

So, those old lead sleds with haul the mail with the right goodies on them.

6" plate. Technically it's closer to 5.5". Venom 225.

I like those numbers. That's moving on. I know what egts are but that about the extent of my knowledge. Closest I've come to that level of performance monitoring was looking at afrs on dirt bikes when trying to really get them dialed in. What are you looking for with the exhaust temps?

I'm pretty happy with how this thing does given my lack of ability to drive it. The guy who had it before me was kind of a bolt on performance guy but I feel like he did a little homework. He was on scream and fly and referenced racer who now that I'm doing the math I'm thinking is your friend. I'm still learning the ropes. Kept it from chine waking a couple times last time out. Long way to go though.

Yep, racer is Alan Stoker.  Probably one of the best OMC guru's on the planet until he retired, sold out and moved to Florida.  He's is my got to source for info and the one that has helped me learn what I know about building bad*** OMCs.  OMC engineers even went to him on advices when they were investing money in outboard racing program.  He is also the one that developed the cooling mod for the 3.0.

 

As for egts, metal from the pistons usually starts going out the exhaust ports at 1,280 degrees.  The e-tec use a special a coatings and other new materials and different technology so they can run around 1,400 degrees.   Those hotter temps and leaner conditions is why they get better fuel economy and run so much cleaner.

 

The more you get it up on the pad and get good bow lift, the faster you can go, and the more it's subject to chine walk.  My Javelin R20 is running on about two square feet of hull surface when it's flying. 

 

You might want to see if you can find any info Paul Nichols, Nichols Marine might have.  He is very good a tuning and blue printing hulls.  I don't know if he still is but for years, he was the man behind the wheel and did the work on Bullets hull for all of Bullets records and test runs. 

I think I found him. Would he be lake Chickamauga area? The website is mostly geared toward outboard performance but I imagine it's the same Paul Nichols.

When you blueprint a hull are you mostly trying to ensure that its true and symmetrical on both sides?

On the trailer, it's hard, but not impossible, Basically, it's taking a two foot flat, hard, smooth surface sanding board with 320 girt wet/dry and start wet sanding the last three to four feet of the pad and the the first riser on each side. You work in a V at about a 45 degree angle back. After an initial sanding that takes the shine off, check for shiny spots, then see if they are shallow enough they will smooth out or need to be scuffed and a thin layer f filler applied. You don't want to sand through the gel coat. A lot of Stratos hulls have a hook in the last six inches of the pad to help them get on plane quicker. I fill that in so the pad is flat. Now, if it was a Allison, you would ruin the hull if you filled in their hook. A lot of Stratos hulls have a large hook at the rear of the first riser, don't mess with that. If the boat is fast enough the pad is going to lift it off those anyway. The idea is to have all of that hull area smooth and flat with about a 320 grit finish. Some spray primer on that area and not sand the primer. That leaves the finish they want. While doing this, you also do the sides of the pad and sharpen the edge.

I usually slide one back on the trailer and brace it up, to get the trailer out of the way, Needless to say, laying on your back and wet sanding, killing your arms, is enough to discourage most from tackling this. My 285 Pro gained seven mph, just from doing this to its hull, but it also had 300 hp pushing it.

You've got a da** impressive knowledge on these things. I'm a total beginner so keep that in mind when I ask this.

Lets say you flip the boat over and look at it that way. The keel then is like the roof ridge. The highest point when upside down The first rib from the ridge would be the first riser? I'm making an assumption that the pad is the back maybe three feet that falls between the first risers. There's a real small back part that steps up. I'm assuming that is to channel water to the prop. What is that called?

Is the hook what gives it the lean left when just starting to trim up?

I think I'm picturing exactly what you're talking about but I want to make sure.

I hope you are flipping just for the sake of discussion, because to flip it to do the sanding, that one would be tons of fun.

The pad is the bottom most section of the hull, about 14" or so wide, depends on the boat, with a very slight V shape, and may even flatten out completely as it gets close to the rear.

Using your upside down reference, you will see about a 1" to 2" straight side drop to the first riser. Then that riser will extend over and there would be another drop to the next riser. It is built this way so as the boat gains speed, each rise lift's a little more of the hull out of the water and reduces hull drag, so it can go even faster. Get it going fast enough and only a few inches of the very back of the pad is actually touching the water.

That stepup you see in the back of most all high performance type boats is just for a built in offset. Works just like a titter totter, They get that part of the boat out of the water so the weight of the motor, batteries, fuel and all the other crap in/on the back of the boat creates a leverage point at the back of the hull there to lift the bow. Then you add the jack plate to set the motor a little further back, if needed so the weight of the motor is in just the right spot to help leverage the boat to the perfect point so you have just the right bow lift and the motor vertical to the water so the prop is applying a straight forward push. You see tons of boats running down the lake with the motor trimmed way out, well beyond vertical. That usually means they don't have enough setback and the motor is having to use power to lift the bow, or they are just flat over trimming the motor.

A good way to check and see how yours it set, Level the hull, and then level the anti-cav plate so the motor is vertical, then mark you trim gauge where the pointer is at so you can tell how much extra trim you are trim you are using to get the hull up. With that 10" jack plate on my Javelin, I can't even get to vertical with my motor before it starts to slip.

Just so you understand, the reason you want about a 320 grit finish, that lets the water start forming micro bubbles of air between the hull and water, so you are actually running on a pocket of air. Wax a hull and it's like running on a pool of glue.

As for the hook and the lean, that's just the Stratos hull. They actually recalled a bunch of hulls on some of their 19SS and 20SS hulls because of that and a very unstable condition they developed. They tried a new design, go faster hull, on those and found out it was dangerous for the average boat owner to drive, so they swapped them out for their old style hull.

Yep, just for discussion purposes. I don't love the idea of overhead wet sanding but I love it alot more than what it would take to flip one over.

Alright I'm getting a better understanding of how this all works. I crawled around under it this afternoon and checked out everything you're talking about. I've looked at it before but it starts making more sense how it works when you're armed with some knowledge. Now I can kind of visualize where the hull is at in the water when I'm feeling it step its way up. Pretty neat stuff. Kind of a simple concept with a whole lot to it. The leverage point makes perfect sense now that I'm starting to get a basic understanding.

I did what you said checking where the outboard is perfectly flat in relation to the hull. It's about 3/4 up on the gauge. Then its got about another 8 degrees at the anti cav plate to the end of the trim range.

I need to totally revisit how I'm driving this thing I think. There's a little more to it than this but I'm basically hammer down out of the hole, once it planes out I start trimming up. I'm on the trim like its the throttle. I don't even think about letting off the trim until I'm almost topped out. Then sometimes I pause and bring the plate up a little. Then I trim all the way out. Then I watch the pressure gauge and start messing with the plate more. I'm thinking now that's all wrong.

What you're saying about it being ideal for the prop to be pushing forward rather than lifting the hull makes a he** of alot of sense. I never even thought about that before now.

Now, I'm the same way one the trim, as soon as the hot foot goes down, the trim starts coming up.  My boat comes out the hole strong and fast, doing it the way I do, the motor totally changes sound as it lays over, you can hear the cavitation holes in the prop working and it gains a bunch of rpm and it is gone. 

 

You can also adjust that trim sending unit so you can get the gauge to read a little closer to the center when the motor is squared with the hull.  The two bolts that hold it in are slotted so if you loosen them, the sending unit pivots.  It has almost a 1/2" of movement in it to adjust it.  Just don't get too carried away with getting the arm out/up more so that when the motor is trimmed all the way down it don't break it off.

 

One way to tell if you are too high on the plate, when you start off and get to full speed, then lift on the has just a little and see if the bow pops up more, and then drops back down when you got back WOT.  A lot of props, unless they have been tuned for the boat will cause one to do this when you are to high on the jack plate.

Alright well I feel a little better about what I'm doing then. Hopefully I'll get to mess with it Monday. I'll definitely try the letting off the gas thing. Why does being too high cause extra temporary bow lift?

Not sure, just something I've noticed with several boats over the years. My thought is the motor is above that sweet spot and when it's pushing at full power, it's actually pushing the bow down. Let up on the gas just slightly and the bow pops up and you can feel the pad just skipping along the chop like it's just barely touching touching the water.

That makes sense.

Man I love that skipping across the chop feeling. Nothing like it.