STV Euro 2" vs 6" Setback Looking for Advice

[CDN27]

I'm looking for some advice on the pros and cons of running either a 2" or 6" setback for a stock ProMax on an STV Euro. I currently have a 6" manual setback but have been told that 2" may be the better way to go as these boats were built with the ideal setback in mind for "lightweight" 2.4/2.5L stuff.

I'd appreciate some real testimonies and experience with either setup if you have any.

[4Speed]

Try looking at the Aeromarine Research site - Jim Russell he did some pretty detailed Euro Testing with I believe a 2.4 or 2.5. I have a 2010 Euro with a 3.0L 225 sport XS and currently have 6" and plan to add 2" more. Its not much help as my 3L weighs quite a bit more than a 2.4/2.5L. There is another article in Hot Boat that came out years ago someone will probably post for you.

[CDN27]

I just found and read through Jim Russell's write up, very informative if a bit above my understanding of physics. I didn't see any discussion on setback so I would presume he didn't use any?

[4Speed]

I don't believe the test boat had any set back. I have emailed Jim several times regarding my boat and he always responds in less than a day.

[CI STV]

I'm looking for some advice on the pros and cons of running either a 2" or 6" setback for a stock ProMax on an STV Euro. I currently have a 6" manual setback but have been told that 2" may be the better way to go as these boats were built with the ideal setback in mind for "lightweight" 2.4/2.5L stuff.

I'd appreciate some real testimonies and experience with either setup if you have any.

Don’t get fixated on a specific number. Whilst it is true that the STVs have a lot of built-in setback, the most important thing to remember is that every boat has its own optimum setup, and the amount of setback you need will vary, depending on weight distribution, type of prop and kind of power you’re running.
How does the boat run with the current setup? Is it “flighty” on the run or when you trim it out? Does it cavitate and/or take a long time to get on plane (with a typical small to medium pitch prop)? If the answer is yes, then you may have too much setback.
Have you videoed it running to see how it sits, relative to the trim angle? If not, get a friend to video you doing a “fly-by”. Best setup is using minimal trim to get the nose of the boat slightly out of the water. STVs typically don’t need or like a lot of trim, and the faster you go, or more power you have, the more significant that becomes.
Do you need excessive trim to get it to run at the right angle? If so, you may need more setback.
My suggestion would be to evaluate what you have, and how it’s running first.
One thing is for sure, less setback won’t make it faster, unless your motor is sitting a bit too low on the transom now or you can’t drive it all out because it’s too flighty.

[Fish]

I run 6" on mine with a 20" 260 and its set up pretty well. Never tried the 2"

[4Speed]

The engine height in addition to set back is critical on a Euro to.

[El Español]

Hey #CDN27, I’m in a huge research of information for the correct engine height x X Dimension of my boat.

The best of your case is that there ir really specialist of your rig in the forum.

As #4Speed mention, the engine height will be the key point. Your boat will run great with both set backs if the height is right in each one.

in general lines you have to calculate a 4% inclination of the water after the boat passing. Soo as +1” X dimension you have to increase around +1/12” height.

in case of twin engines, as far are the engines, less toe-in is needed.

The prop selection is also involved of the necessary height. If you could have an adjustable jack plate, you could find smoothly the perfection.

best, Javier.