85hp on a jack plate?

[bishopcherrycoke]

Hello again! I just picked up a beautiful old 1974 glastron cv 16. would I benifit at all from a manual jack plate? I'm putting a 1979 cross flow 85hp on it. I'm looking to go as fast as I can and be as efficient as I can. Thoughts or ideas?

 

[JB]

Re: 85hp on a jack plate?

Being able to fine tune the engine height and trim is essential to get the very last smidgen of speed from your rig, bcc. The question is what is that last smidgen worth?

There are a dozen ways to fine tune a rig, most of them cost a lot less than a jack plate.

 

[Faztbullet]

Re: 85hp on a jack plate?

I'm looking to go as fast as I can and be as efficient as I can.

If it was mine I would be looking to trade/sell it for a mid 80"s inline Merc 115, as this are 140 hp at powerhead and 115hp at prop where the your 85 is about 80hp on a good day at prop

 

[F_R]

Re: 85hp on a jack plate?

"Fast as you can" and "Efficient as you can" are kind of oxymorons. Usually, "fast as you can" means it isn't worth a hoot at much less than full speed or different loads. A race boat may go half way across the lake before getting up on plane. Everything is a compromise in boating unless you have a single goal in mind.

 

[bishopcherrycoke]

Re: 85hp on a jack plate?

A new motor probably won't happen for a few years. I'm just trying to get the most out of my current setup. I have my eye on a 4 inch manual jack plate on eBay. I am used to changing props between sking/ tubing, cruising and just me for going fast. I don't mind tinkering before we go out depending on what I wanna do.

 

[Chris1956]

Re: 85hp on a jack plate?

I put a jackplate on my speedboat. What I found was that if I maximize the lift of the jackplate, the effect of the power trim is lost, and I can lose top speed. I also found that it was difficult not to ventilate when trying to pull a skiier.

I have now set the jackplate height where it is a compromise between top speed and "driveability". The boat is still damn fast.....

Be sure to watch the heights of the water intakes for the cooling system. If she sucks air, she can overheat.