Getting out of the hole !!

MarcoIsland

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Joined
Feb 20, 2007
Messages
6
I bought a 1989 VIP 18ft, with the Cobra 2.3 liter engine last spring. It just doesn't seem to have enough giddy-up to get me up on plane quickly. I have to have someone stand on the front, to get it on plane. Someone told me I might not have the right prop on it. Everything else on it seems to be running fine. Any thoughts or ideas would be appreciated.
 

Boomyal

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Aug 16, 2003
Messages
12,072
Re: Getting out of the hole !!

You will be maximally propped when you can redline your engine at wide open throttle (WOT). If you go over redline you have too low a pitch. If you cannot reach redline, you have too high a pitch. (taking too big a bite)

You also need to trim out the boat, once you reach planing speed, before you can make this determination.

If you are already properly propped, then you need a set of these:

http://www.iboats.com/mall/?keyword...=404392915&list_time=1172011555&view_id=39283

I would expect with an average load and an adequate prop that a 2.3 L, in an 18 ft boat, would need all the help it can get.

Smart tabs have made many a marginal boat a new animal.
 

HT32BSX115

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Dec 8, 2005
Messages
10,083
Re: Getting out of the hole !!

All of the above is true.


However, You MUST ensure that you have NO engine performance problems........I.E. The engine must be developing normal power etc.



Cheers,



Rick
 

QC

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Mar 22, 2005
Messages
22,783
Re: Getting out of the hole !!

Also, the 2.3 is probably the highest revving I/O engine ever sold. It needs to be propped so that it reaches 5200 - 5600 RPM at wide open throttle (WOT) under the conditions that Boomyall describes and when the engine is right as HT3 notes. To get the best hole shot you should target 5600 RPM at WOT with an average load. This should give you the best hole shot and maintain some decent top speed. My guess is that it is prop pitched too high (reaches less RPM than noted) or that it isn't running right, or that your expectations are too high.

Ditto on the trim tab recomendation ;)
 

Gary H NC

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Dec 1, 2005
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8,972
Re: Getting out of the hole !!

Also if you have to get someone to stand up front to get on plane something is going on with it.
Do you know what pitch the prop is?
If it was me i would start with a complete tune up and see what your WOT rpms are.
 

MarcoIsland

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Feb 20, 2007
Messages
6
Re: Getting out of the hole !!


Would it be possible if I don't get enough power with the new prop and tune-up, to put the next bigger engine into the boat. I think the 4.3 liter cobra is the next step up. If I did that, what else would I have to change out. Also where would a good place be to look up pricing for the replacement engine.
 

WillyBWright

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Dec 29, 2003
Messages
8,200
Re: Getting out of the hole !!

You would need a complete engine with exhaust manifolds and an new exhaust Y-pipe. About the only thing you might be able to use from the 2.3 is the alternator. The 2.3 is a Ford and the 4.3 is a GM. You would also need to make sure the boat has structure to mount it to. Not all boats with inlines have the support necessary for a V.
 

MarcoIsland

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Joined
Feb 20, 2007
Messages
6
Re: Getting out of the hole !!

What would be the best way to upgrade to something with a little more power?
 

QC

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Mar 22, 2005
Messages
22,783
Re: Getting out of the hole !!

Sad thing is the answer is probably to sell the whole thing and buy something else. There are not going to be any bolt-on performance products for the current engine, and a repower will require a gear ratio change, especially with the high RPM of the current engine vs. everything else. Complete engine/drive packages are usually pretty steep, so unless you find a super deal, a boat swap would probably be less costly . . .
 
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