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4504
01-30-2001, 12:49 PM
Hello
I am new to boating and as such could really use your advice. I recently bought a mini-boat and would like to know your thoughts on the boat and its potential, as far as maximum speed and what I would have to do to obtain this. The pink lists this boat as an 86 Fireline, V1 type pleasure boat, vsl type is 82, hull type is X, prop is O.
I am not yet familiar with the proper terms as far as boat terms, so bear with me and feel free to either correct or inform me of the right terms. Here are links to pictures:
http://pongopix.com/upload2/4504/boat1.jpg http://pongopix.com/upload2/4504/boat3.jpg http://pongopix.com/upload2/4504/boat4.jpg http://pongopix.com/upload2/4504/boat5.jpg http://pongopix.com/upload2/4504/boat16.jpg http://pongopix.com/upload2/4504/boat18.jpg
I have been told that this is a tunnelhull. I am unable to find anything that lists what the maximum horsepower should be. There is a disclaimer on the dash which says the boat was built as a racing boat for competition only, may not comply with coast guard regs, etc.
The demensions are as follows:
The length is 10" 0", the width at the widest spot is 5', the distance from top to bottom at the rear (transom?) is 20". It currently has an Evinrude 30 outboard. The plate between the boat and engine (offset plate?) is 13 inches long and 7 inches from top to bottom. The distance from the very top of the engine to the very bottom is 44", from the bottom of the cowling to the very bottom is 32", the distance from the bottom of the cowling to the middle of the prop is 25", it is 38" from the top of the cowling to the middle of the prop.
Does this mean that this is a short-shaft, long shaft, 25" shaft?
We took the boat out a few time and top speed was an approx (speedo broken) 30-35 mph at 4,900 rpm. I have been told that this engine could go 5,500 rpm with a different prop and get up to about 40. The thing is this: the boat feels very fast and stable at top speed. We were tucked down and I was thinking "wow, we are flying"!. Then we got passed by a kid on a jet ski.
Well, I am not into getting passed by jet skis. I need to know what is the most motor this boat can handle, type (longshaft, shortshaft, 20" or 25" etc> ) and any other tips, such as a prop, etc. I won't get over my head, I just want to go a lot faster. I think this boat should be able to crack at least 60 mph without being a hazard. What do you think?
mike

thebone12
01-30-2001, 06:12 PM
The best bet is to go with a 2cylinder 50 hp or 48hp johnson or evinrude. any more weight than these engines will make you porpose like crazy. You should also get a adjustable jack plate and a nose cone from Bobs marine on the lower. With this set up you will be at the edge of the proformance. The problem is not the hp but the weight. With a 50hp you will be close to 57mph. good luck

4504
01-31-2001, 06:13 AM
thanks for the reply
I am just trying to clear some things up:
1. So, should I be looking for a shortshaft, 20" or 25" or ???
2. By my dimensions, what is on there now? If it is a 25" or 20", would I be better to switch to a ???
3. I am going to re-paint the boat. As such, is there anything I can do to the hull beforehand to make it speedier or more stable, before I lock it all in with new paint?
I very much appreciate the replies...this is kinda a start for me before I get into any more serious boats. I know that I have a lot to learn and at this point I'm just trying to "get my feet wet".
thanks
mike

thebone12
01-31-2001, 10:35 AM
your engine that you have now is not a long shaft. It is a short shaft of 15inches, a long shaft of 20inches 50hp on a jackplate will work but not an extra long shaft of 25inches. As far as the bottom goes just make sure everything in straight and flat. It may have deformed from sitting to long. As far a a marine paint for your boat go with awlgrip or emron. They are the best! Good luck

4504
02-01-2001, 07:15 AM
thanks for the help
I would like to try and clear up just two more things, as I am looking at a specific engine right now.
1. can anyone tell me with my setup what the manimum weight of a ob motor my boat can handle? Then engine I am interested in now weighs 230 pounds. I have no idea what the 30hp evinrude I have on there now weighs.
2. From the current setup in my boat, I see that the prop, specifically the middle of the prop, is about 6 inches below the bottom of the transom. In other words, when the boat is level, the prop is sticking below the bottom of the boat about 6 inches.
I have heard that this is not that good for performance, in that this is producing drag. Makes sense. Now, altho I am not doubting the previous post which lists my current engine as a 15" shortshaft, a person who has actually looked at it insisted that it is a 20" longshaft.
If I understand what I have read so far, an ideal setup would be is that the prop, specifically the middle of the prop, would be about even with the bottom of the boat. As I already said, my prop is about 6" below the bottom of the boat.
Is this true, about the prop being even with the bottom of the boat being the best setup? If so, and my engine is already a 15" shortshaft, obviously there is not much I am going to do to raise the prop up a little higher with another engine. However, if my engine is a 20" longshaft, getting a 15" shortshaft will raise the prop up to be about even with the bottom of the boat.
Thanks guys for the replies and I appreciate your replies more than you know. If you can help me with the weight and shortshaft issue I promise to quit asking anymore.
mike

FCnLA
02-01-2001, 10:37 PM
Nice looking ride. Kinda looks like mine except for smaller. It looks like a tunnel. Need to see pics from the rear to make a sure. You definitely want a 15" mid. From looking at the pictures, it looks like you have a 15" motor, but your prop measurements make me wonder. I can take some measurements at the boat store down the street from the shop and get back with you.
A 50 horse OMC with a 15" mid. would be a good start. You also need a adjustable jackplate to fine tune the depth (power trim would help too). The setback plate (extends the motor rearward, moves the center of gravity rearward also) does not look like it would support a larger motor. "Surfacing the prop" decreases drag and will reduce trim angles. If you surface the prop, you will need a nosecone with a bottom water pickup. This fits on to the front of the current gearcase and would be epoxied and molded into place.
I like you am fairly new to this fast boat stuff. I've had mine in the water for about 4 years. Only until last year did I get close to where I want to be. My fastest speed has been with the centerline of the prop shaft even or slightly above the pad or riding surface. I measured this by using a carpenders level and leveled the boat with the tongue jack. I then leveled the cavitation plate (horizontal flat area above the prop by adjusting the engine angle). Finally take long straight edge place flat on the pad back to the gearcase. Super high engine heights can cause a loss of drivability like difficulty getting on plane because of prop cavitation.
Hope I've helped ya. Glad to see more people getting to fast boats. FC.
[This message has been edited by FCnLA (edited February 02, 2001).]