Hello Stinger friends!
I'm the owner of a Stinger 260 from -88 by the name of Wet'n Wild.
Currently her condition is awful since I haven't had the time to treat her in the way she deserves.
So, she will be repainted, or at least the paint will be removed and the gelcoat condition revealed. Then we'll see if she needs repainting.
Anyway, since I'm going to make an overhaul on the exterior, why not on the interior... And since I'm at it, why not the engines?
Everything won't be done at the same time, of course, one thing at a time. Lets talk about the engines, drives and props.
I started out learning the theory of CSB-tuning and has been reading about it for the last 2 or 3 years. Producing 450-500hp from a naturally aspired Chevy Small Block 350 is doable. The environment and fuel economy is not considered. But, I'm now in doubt... Is it really worth all the money? What will the result be? How will the boat behave? Will the drives be able to handle the power?
A lot of questions and no answers before the money is spent... So I would like to look at the "problem" from a different angle.
Driving a boat in excess of 60kts is not without risk. 70kts... Well... I'm a father of two now and I've got a lot to live for, so lets settle with 60-65kts.
What power will be required?
If i use the highly unscientific formula "current top speed / current hp * new hp" => 46 / 520 * 800 = 70kts. Well, the fact that resistance is increased by the speed to the power of 2 (is that how you say it in English?) and not by 1, the boat might make it to 60kts, i guess... ? Maybe more?
Anyone with experience of a 260 going in 60kts? Or more?
The drives are Volvo SX from 88... Far from the best, but according to a service technician they should be able to handle 600Nm if driven carefully... Whatever that means... Well, I won't run in a race and I want to live, so... Maybe they are strong enough.
Will the shape of the lower unit be a problem? Will it prevent the boat from reaching 60-70kts?
Max rpm will probably be somewhere around 4500... The drive gearing is standard (whatever that is
).
Currently there are 25" props on (totally wrong), which forces the engines to run on a lower rpm. Currently, max is 3800. Way too low. A sailboat have a better acceleration.
What prop-pitch is standard on the 260? I'm guessing 21"... So with an increase in power from 260hp to 400hp/450ftlb, a prop-pitch at 23" might be right? Or is 25" the better guess (it would save me some money...) ? Anyway that's a smaller problem since I can test the 25" first and see what happens... maybe a change in gearing will be enough...
Estimated launch year: 2015.
Summary:
1. Power requirements to push a 260 to 60kts or more? (lets skip the "how to increase the power" in this, we can take that in another thread)
2. Volvo SX: Will they break or hold?
3. Prop-pitch at 23" or 25"?
What do the rest of you say?