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15" mid question re: short ram

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I have a question about the 15" mids and know one or two of the reliable experts could assist me.

Putting a drag mid w/short ram onto my RR that has a hydraulic jackplate and I have heard some others express concerns about this ram not being the most lake friendly....in terms of not having enough trim travel. Would I be O.K with the hyd. jack and short ram or is a long ram a better application. Secondly, any problems fitting a long ram into this mid if neccessary?

I would assume the hyd. jack will allow me to change height at ease for diff. props or at speed over a manual, but will trim be too negative?

Thanks in advance. biggrin.gif

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Dreamer,

Most guys run either wedges or have the hydrodynamics plate made with around 2 degrees of positive trim built in. With your jackplate and a short trim ram you will not be able to trim to a neutral position, which means you will always be running in negative trim and at higher speeds you will be wanting to trim up to neutral or VERY little positive trim as the front of the boat is getting pushed down. If you have any shallow water to deal with a short trim is not the most user friendly set up. You can add the large trim ram to your mid with no problems, or you can get a hydrodynamics plate made with the offset built in or run some degree wedges. If I were you I would sell your hyd jack plate and get the new one your plate is REALLY heavy and you do not need a hyd plate, or just switch it to the larger trim ram. Let me know if you want to swap for a large trim ram out of a 15" mid, I have one.

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What RPM said, I would ditch the hydraulic plate, and get a hydrodynamics plate. Ask Chuck at hydrodynamics to make you a plate with 5 degrees positive trim in it.

I would NEVER run a hydraulic plate on a rocket, weight is an issue and so is repeatability.

You can switch to long ram if you want, as the short is a pain in the ass. Specially if you boat in shallow water.

RT

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Yep...ditcth the hydraulic jack...

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Stv Dreamer, I would go with the long ram. My offshore race came with the short ram. I have a stock 5 inch hydro dynamics jackplate on the boat. You can get positive trim on the boat but very little. It it good enough to drive with, but barely. If you plan any shore stops, it will not cut it, at all. I plan on switching to the long ram on my boat. Wayne Tripp says the short rams are hard to get a hold of and wanted by some. He says there should be no problem in trading for a long ram. If any one wants to trade . I have one with about two hours on it. I'm lookin for one in the same new or near new condition.

Kurt

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THANKS, will the Hydro plate w/5 degrees work better with the short ram for shallow water or will I still need to remove the short ram too? ALSO, is long ram the same as out of a 20" mid or different?

Chuck's price in CDN $$ w/ 5 degrees and the price of a long ram new/used.....will keep my short. AND what do you think I could get for my Hydraulic jack plate?

Thanks guys.

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The short ram has about 1/3 the travel of the standard ram. If you want to trim out the engine to beach the boat on a sand bar, the long ram is the way to go.

For drag racing, the short ram is better. It trims faster and more reliably. The problem is that they are expensive and on back order from Mercury. No one knows when they will be available.

An STV needs less tuck under to launch than many other boats. 2 degrees of POSITIVE wedge will allow the short ram to work well. It can be added with wedge plates or by modifying the jack plate.

On my personal lake STV, I use the long ram. I have a new short ram sitting in my garage, I choose not to use it on my lake boat. And NO it is not for sale!

STV Dreamer - If you want to trade your short ram for a long ram, let me know. I know of several guys that will trade out with you and at least pay for shipping on both rams. Drag racing is big around here and the short rams are in demand even for lake and river use. Let me know if you want to change yours, I will get you a good deal.

They are easy to change.

If you are looking for a new 5-6 inch Rapid Jack for an STV, A friend has one that he will let go at a good price. I will call him and get the price and the exact length of set back.

I hope this helps.

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I think the boys covered it all. In MY opinion, you need the positive trim in the jack if you want to run the short ram. While it will work, if you ever have a load or are running down wind trying to air it out you won't have enough positive trim. Any way you look at it the short ram sucks of you want to beach it. Consider that you basically can only trim the motor just past neutral. I know at least two local guys that would trade you and do the work for you to make the switch. These rams are kinda funny, guys that want them really want them the rest hate them. I am swiss on them. If you want trim speed with the long ram, get a mercruiser trim pump.... if you wanna be REALLY fast put one on the short ram...... than add 24 volts.

RT

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All fixed.......unit came with a long ram. Stinking minty too. Can't wait to hear it all fired up. Thanks agin for all the input.....you know I'll be needing more soon.

Later

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Brandon,

If your jack plate does not have any additional positive wedge, adding 2 - 4 degrees in the form of wedge plates or by modifying the jack plate can help give you more positive trim angle that you MAY need or want.

With the short ram, your total amount of trim travel is limited. For drag racing you want a bit more tuck under (negative trim) than you need for a lake boat, in order to get the best launch. We usually set STV's up with a couple of degrees more positive wedge and use a shipping bolt in the first hole to limit negative angle travel.

For lake use, this same set up will work for many rigs, but some may want as much as 4 degrees of wedge. It really depends on the props you run, and how much set back you have.

The bottom holes in the jackplate can be relocated to give additional wedge instead of using the wedge plates.

I hope this helps.

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Thanks wayne, just finished riggin the River Rocket we have over here and we have the short ram on it and it only trims just barely above level so were gonna have to add atleast 2 degrees imn guessing

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