Performance upgrades for my 240 SD?

[So Cal Sundeck]

Hi everyone. I'm a newbie to the site. I live in Southern California and bought a 240 Sundeck last year. My wife and I absolutely love the boat. It's so versatile and has everything we could want. the only thing I was wondering was if there are any performance upgrades (props, air filter, etc) that are worth doing? My boat does about 46mph now +/- 1mph and that is good, but just wondering if there is anything worth doing. From the research I've done, it doesn't seem like it, but I thought I would ask on this site to double check my findings.

Thanks very much.

 

[Searay Jim]

Unlike with motors in cars, boats currently have no emissions restrictions so for the most part, boat motors are operating at about their peak performance. However, even if there was a little room for improvement like with cars, 25-50 HP in a boat would almost go unnoticed where in a car you might actually feel it. It takes $$$$$ :grin:

That said, everything is always for sale. I can hook you up with a Sundeck that does about 20 MPH more. :grin:

And you're right about the Sundeck. It's hard to come up with a boat that is as versatile, especially the 240.

 

[So Cal Sundeck]

That is what I was afraid of. I was just hoping that there could be something done to help it. I had a shop not too far away tell me he could put new exhaust manifolds and utilize my corsa thru-hull and I might be able to pick up 3-4mph, but the cost was going to be around $2000. One of my buddies basically told me it's about $1000 per MPH. I just thought there might be some trick or something I could do, but I guess not.

Wow, you've got a 540 in your 240? That's awesome. I absolutely love my boat. I get so many compliments on it. I love the Corsa Thru-hull exhaust too. It may not move out like a fast boat, but it sure sounds good idling through the marina and definitely grabs attention.

Thanks for the reply. Do you have any pics of your motor? What drive are you running in your boat?

 

[ehaze]

you could always go with something like this.

http://www.livorsi.com/catalog/extreme_superchargers.htm



my boat seems fast but another 10mph wouldn't hurt

 

[Searay Jim]

$2000 for a set of after-market manifolds may be a little optimistic these days. But that's a starting point. Stainless Marine, which is what I have, are pretty much the hands down favorite as far as inexpensive and high quality, and $2000 is in the ballpark just for them. But you won't get 3 - 4 MPH just from them. Better sound yes, a little more top end, eh, maybe, but not to justify $2k.

My buddy that has the shop ho built mine, has done extensive testing lately on several different set ups, but ones where there are claims of significant gains with big blocks primarily. He's one of the few that has a dyno with a prop-shaft adapter "AND" that sets a motor up in the dyno room with full dress and full wet exhaust as it will be in the boat. Awesome real world results. Example, the new Dana manifolds for the 496 (no where near $2k) claim something like 46HP just with them. He proved on a dyno that their claim is pretty dead on, and more, they beat the gain of custom Lightning Headers which is pretty shocking considering the cost for those.

Anyhow, I know a few people that have added Prochargers to 350 MAG's with pretty good results, including one that did it last year and before the year was out, blew it up running too lean. Over the winter left it with my buddy to stroke and set the Procharger up right, and it's running really strong now as a Procharged 383. However, we're back to talking about $10k or more once it's all said and done.

My buddy has a funny, but so true thing he tells people that ask, "how fast can you make my boat go?". He smiles and says, "I can make it go as fast as your checkbook will let me." Speed costs. :grin:

Give me a few minutes on the pic. I need to shrink one down to micro size for this site, otherwise post a 50x50kb micro avatar style pic. :smt013

 

[Searay Jim]

Let's try this again. :smt017

 

[Searay Jim]

Oops' missed the Q about drive.

Still running the BIII. Only change was going to 30p props.

I have an opportunity to swap for a BIII XR right now, but I'm done spending money on the boat for a while. Besides, gearing and props are restricted on the XR so while a 2:1 ratio is fine, and what I have now, they ended up not producing a 29 or 31p XR prop-set so I'm stuck with 27p and no option of re-gearing to 1.81:1 gears. The XR was designed for big heavy sport cruisers with big Merc power.

In the mean-time, I'm still dealing with cavitation burn with the old elephant ear BIII props but so far this year it's looking good with a cupped 30p aft prop.

 

[So Cal Sundeck]

Jim, thanks so much for the info. I really appreciate it. Yeah, I figured this much on the upgrades from talking with some others. I was unsure on the supercharger as well as some shops told me that it wasn't a good idea to 1) supercharge the 350MAG and 2) the drive probably wouldn't hold up. Oh well....I love my boat still and didn't get it because it was the fastest one so it's all good. Maybe after a few years I'll break out the checkbook and start doing some mods. As for now, I'll probably just enjoy it how it is. Thanks again for all of the info. Really good stuff. The pics are awesome too. That motor is SOO clean.