trying to find a happy medium with the hydrostream viper

[fordboys4x4]

Some of the information I passed along on a previously thread it was suggested I research props, set up and rigging.
the set up is a 15' Hydro stream viper,re-cored, 2.4-200 merc on a 3" Vance jack plate. When being used outside the river into the no wake zone, it lugs motoring and drinking a lot of fuel. We figured the best way to achieve the happy medium is to have a hydraulic jack plate and can adjust on the fly so to speak. We ordered a T-H marine Atlas 4" set back jack plate . The issue is that the advertised 4" set back is not as advertised! it is 4-7/8" set back !! My question is : Can we use this new Jackplate given the fact it is 7/8" over what it is supposed to be? We called TH Marine and they said they no longer sell the 4" set back jack plate and uses the 4-7/8" and boxes them as 4". I looked into Bobs Jack plates and not sure which way to go. Can you assist or any ideas, I would appreciate your thoughts

[transomstand]

I'm lost as to the thought process of engine lugging and poor fuel economy being controlled by a jackplate

[fordboys4x4]

the boat is not being used on lakes as of now. If we were, I would not be posting this! We live in Gloucester, Ma. and the calmest waters are on the Annisquam river. However,to get to these places we have to go through choppy waters and have trouble maintaining low wake speeds and the engine works harder because of the fixed position of the manual jack plate. It is set up for the calm waters
As I stated, We need to make the adjustments when approaching choppy waters and the best bet is the T-H Atlas hydraulic jack plate. My question was to find out if anyone has used this brand of jack plate and would a 4-7/8" set back would work on the set up we have. I am hoping to get some input as to keep the Atlas or get a Bobs Jack plate

[LakeFever]

The problem I see is porpoise. Vipers porpoise a lot as it is and the more setback you add the more porpoise you’re going to get. Adding the weight of a powered jack also increases porpoise. I can’t say what difference the extra inch will add to the handling and porpoise of the hull, I haven’t owned a viper. Ive had a few streams with jacks and one without. I like my hydraulic jacks for my needs they fit the bill. I have kids and sometimes cruise fully loaded and other times I’m alone ripping. With the hydraulic jack and some different props I can do both easy with a jack. My stream without while I believe drives the best, almost no porpoise and excellent handling, it is a compromise one way or another. When I had the engine height set good for speed runs if I put my family in the boat I struggled like crazy to get it up on plane it just spun like crazy trying to hook up the prop. Had to try over three times sometimes which wasn’t fun at all. With the jack I crank it down to get on plane and easy peasy. Noticeable increase in porpoise though. There’s a price for everything

[fordboys4x4]

Thank you for your reply! most informative and gives us something to look at. It does porpoise now and once you throttle up it will go away. Generally there is no more than 2 people on the boat so it's not loaded down. Thanks again !!

[Merc Speed]

I installed a Bobs true tracker stabilizer plate on my stream with a bobs 4 inch jack plate. I have a 18 foot boat but the acceleration is great with no porpoise with the plate all the way down trimmed in. It might help your Viper with the larger jack plate.

[fordboys4x4]

Thank you for your reply! We have made some changes with props so far and utilized a T-H marine hydraulic 4 inch jack plate but I will look into the Bobs true tracker stabilizer plate! Thanks again

[Carter Powell]

Is your motor a carb or EFI motor. So many things not mentioned here. What is your altitude where you boat. What type of max RPM are you turning? When the boat is lugging have you looked at your plug color? I would bet money that your problem is fuel related if the motor is in good tune. If it is a carb motor try going to smaller low speed jets.

Carter Powell

[fordboys4x4]

Thank you for the reply! It is carburetor and through a lot of trial and error we found that we were using the wrong prop. We are now using through hub prop which helps low speeds and better fuel mileage but will go back to the out of hub prop for lake only use. Thank you for your reply.

[Carter Powell]

Whether it is an over hub or a thru hub should make no difference on the fuel usage at low speed or high. If you can find out which low speed jets you have and compare those to known stock jets I would do it. Remember altitude has a tremendous effect on how a carb motor runs.

Best wishes, Carter

[fordboys4x4]

I will find out about the jets and get back to you! I do not know if the carb has been messed with.

Thanks again!