Proper setback

[specboatops]

I have been told and I might add I have read as well that the proper amount of set back is typically 1" for every 1' of your boat. So if I'm running a 20 foot boat I should have 20 inches of set back from my last running surface. Here comes the question, what do we consider the last running surface, like on stv,s that have that extra on there transom do you measure from the last part of your pad or the last part of that extra area i'm referring to??

[specboatops]

BUELLER.............??????????????????????

[Moodgam]

I have never heard of that particular formula for determining the proper amount of setback. I'd be interesting in reading that article if it is available.

[Ted Stryker]

The amount of set-back is measured from the last wetted surface while the hull in on plane... Let us know your about your rig and set-up, and we'll try to help you if we can...

[imq707s]

I think the the "propper" amount of setback is more of a factor of your hull/motor combo. Also....one persons "ideal" setback may be different from other peoples. It all depends on your setup.

[specboatops]

The amount of set-back is measured from the last wetted surface while the hull in on plane... Let us know your about your rig and set-up, and we'll try to help you if we can...

Gambler SuperSport 20 foot running 11 inches of set back ( approx 20 inches from last wetted surface ) 2.5 200E.F.I. worked by Ruck. Few extra goodies here and there. Just trying to clarify the set back thing. Any and all advice appreciated.

Chris

[SUPERBASH]

As Bash remembers & read...12" setback max. up to 21' ....then 1" for each additional foot. AS A GUIDELINE ONLY.
(It makes a little more sense too.)

[specboatops]

I did do a search BEFORE I posted this thread thanks for the post, like I said that's what I was kinda thinking just need a little reasurrance.

[SUPERBASH]

I did do a search BEFORE I posted this thread

Good man !!!

[Ted Stryker]

I'm assuming your hull is the Gambler that is a Bass boat made in Florida... I've never owned one, but I'm thinking it is around a 1500-1600 lbs. hull... 11" of set-back is a reasonable jack plate I would think, provided you have a good biting 3-4 blade prop... A Tempest and Trophy props are great props for full size Bass rigs..

[Moodgam]

I use to sell Gambler Bass Boats manufactured by Maritec Industries, Bob Ackerbloom and am familiar with your hull which is 20'3" if I remember correctly. 10" of setback was the magic number on that hull. Predator props performed really well along with the older A40 and A45 series Trophy and Tempest. The M series which we referred to back then as the Pro Series from Yamaha also performed very close to the Tempest. We use to run 26" pitch with stock 200 Merc EFIs.

[Ted Stryker]

My Father used to own a 1994 21'10" XDC Bullet that performed exceptionally well with a 27" pitch Predator 4-blade, great props... The Bullet had a 1994 XRi 200 Merc and it ran 82-83 mph unloaded with a 14" jackplate and the factory Alpha style gearcase... The engine was as high as we could get it while still retaining full water pressure with the factory pick-ups...

[specboatops]

I'm assuming your hull is the Gambler that is a Bass boat made in Florida... I've never owned one, but I'm thinking it is around a 1500-1600 lbs. hull... 11" of set-back is a reasonable jack plate I would think, provided you have a good biting 3-4 blade prop... A Tempest and Trophy props are great props for full size Bass rigs..

Ted, actually it is a closed deck ski boat. I'm sure the bottom is the same as the bass boat but the cap is much different.

[specboatops]

I use to sell Gambler Bass Boats manufactured by Maritec Industries, Bob Ackerbloom and am familiar with your hull which is 20'3" if I remember correctly. 10" of setback was the magic number on that hull. Predator props performed really well along with the older A40 and A45 series Trophy and Tempest. The M series which we referred to back then as the Pro Series from Yamaha also performed very close to the Tempest. We use to run 26" pitch with stock 200 Merc EFIs.

I do run a 26 trophy, I've called Gambler a couple of times to ask questions but noone is ever there that seems to be able to Answer these questions, or I ask for a return call ..........to recieve none I'm sure they are a very busy outfit and answering questions on a boat they no longer build falls to the side if ya know what I mean. Not to ask a dumb question, but if you go past your ideal set back how does this effect the ride???? what type of charectoristics would I see/feel??

Chris

[W. Tripp]

Moving the engine farther back does several things.
1.) It moves the WEIGHT of the engine rearward, and changes the balance of the boat rearward. This makes the boat harder to plane off, but it is easier to carry the weight at speed and can give a bit higher top speed.

2.) It gives the lift of the prop more leverage to lift the bow of the boat with less positive trim. But it also reduces the effect of tail lift from the prop.

3.) Most importantly, it allows the prop to be raised relative to the bottom of the boat. This can give an improvement in top speed with a slight loss in the ability to plane off. The general rule of thumb is that every inch you move rearward allows the propshaft to be raised 1/8 inch.

A boat with too much setback has a hard time planing off, and can be "squirly" to drive. Finding the correct amount is part of set up of any boat, and the amount of power, gearing, and choice of prop(s) plays a big part.

I hope this helps.