Xtb 21 preferred jackplate setback

Dave Hensley

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Thomas the fastest XTB I ever saw had the motor offset on the transom to the left and was back 11". The pad is so narrow I think loaded they could use a 14" set back. I haven't tried moving moving one across the beam.
 

ally2dextreme

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Thanks,yea I really want a 10-12 plate but there not making them any more.All the boats I have here are 6 inches and I think more would be better.
 

Mrbuck50

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I will let you know.........I have a 10" plate and just bought a set of 4" spacers. I will be installing them in the next few weeks. The guy I bought my boat from (long time Allison guru) suggested that the XTB's need between 12" and 14" setback to perform at their best. I will keep you posted.
 

ally2dextreme

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Great !the bad thing about alot of setbackbis poor hole shot....I'm going to have a product for that very shortly that should help us all out
 

silverbullet02

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Bill told me to run 14" on my 89 and it worked real well with the 150pm in the low 80s and pulled skiers nicely too.
 
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Dave Hensley

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Mine is 10" back right now. With 2 people and a light load, 29" box stock RE 3 Mazco, stock 225 ProMax and stock 1.87 Sportmaster it is comfortable at 92MPH. Motor is dead even. Mazco blows bad on holeshot. Fishing boat not race boat. Other things to work on. Need to talk to Tbuck about a better prop. Three batteries, onboard charger and 22 gallons fuel. Biggest issue I have with the boat is the lean with one up and all the rear weight. Darris put a well for one trolling battery in the front compartment of the later models. It is there for a reason.
 

Dark Allison

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Thomas when I talked to Darris about mine he stated some perform better with less. My XTB21 is a 96 . He stated due to differences built into the transoms the 94-96 they perform better with the 9-10" jack plates . As Dave stated my buddy Tommy said he once saw one they moved the motor 1/2" to the left and the seat 1" to the left and it drive like a center steer boat.
 

ally2dextreme

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Thomas when I talked to Darris about mine he stated some perform better with less. My XTB21 is a 96 . He stated due to differences built into the transoms the 94-96 they perform better with the 9-10" jack plates . As Dave stated my buddy Tommy said he once saw one they moved the motor 1/2" to the left and the seat 1" to the left and it drive like a center steer boat.
OK ,Todd told me when they took out the floor locker they changed setback but my 91 looks like the same as the 90 and the same as the 85....94 must have made the change.. All mine have 6-8 I think they need 12-14....I'm thinking about making some new jack plates because Allison only offers the short ones now..
 

ericgolf69

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I got a 5.5 inch now and going to put a Bobs 10 inch on it with 15 inch set back and see how it does 1990 XTB with 2.5 promax , I have three batteries and 22 fuel , with about 50 to 75 lbs of gear , and a MinnKota Tranova whitch is about 50 lbs on left front 28 pitch chopper and it runs 6000RPM easy at half to 3/4 throttle ,I have not GPS it yet but it is fast now
I am just asking ,what do you guys think ?
 

ericgolf69

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Thomas the fastest XTB I ever saw had the motor offset on the transom to the left and was back 11". The pad is so narrow I think loaded they could use a 14" set back. I haven't tried moving moving one across the beam.
did they stack to 5.5 together ?
 

ericgolf69

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Well have not seen the answer but I think that I will add a 10 inch Hydro. jack plate to my fixed 5.5 and I think that will be enough with a 28 chopper , but i will try a 4 blade 29 or 30. So I will be running 15.5 with a 2.5
 

SLOmofo

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Yes, mine has been trouble free. I always check the bolts to make sure they are tight. I think people have problems is because they run till something breaks. Here is a view.
17298
 

ericgolf69

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Wow thank you for the picture, I love your setup ! I have decided to take it down to Reynolds racing and have then put the CMC 10 inch hrdo. jack plate on it . I have been an auto tech all my life and just got eye surgery and trying to get it all done before summer weather gets here. I am still a good tech but just an older and slower worker. I am running a 28 chopper and i can blaze it to 6000RPMs in no time and at half throttle so I know i am going to have to get another prop and don`t know whether or not to go with a 4 blade or what. Plus fishing all the time my prop is razor thin and I want a beefy prop just in case i hit some sticks on the river , what is your thoughts. Thank you for your time. The last Allison I had was a 1979 SXT 17 running a mod 200 OMC that put out a lot of HP ,it would run a 100 easy but it only weighted 450 pounds empty, I straight line the bottom and put hooks in the back edge and it would rock .
 

SLOmofo

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Loaded to fish prop and height will be different then stripped and ready to rock. Reynolds is a great choice from what I've heard. A beefy prop will get you there and back, where as a thin prop is soon to crack. Stainless by the pound and pistons by the drum...LOL
Here is another view17303
 
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