My intro

[deckofficer]

Hi all, name is Bob and I've been into hot boats and rods for 40 years. I'm retired Merchant Marine (no hot boats in that line of work, 18 kt stuff) and in the process of buying a lake house with pier, dock and lift. I'm looking at the SVT and others of that type (little weight, massive hp) and am here to learn about what is new in performance boating.

This is from 25 years back, taking my folks for a spin on Lake Tahoe.
http://i1236.photobucket.com/albums/ff452/deckofficer/Old%20ides/Image88965x700.jpg

And this is my road equivalent to a SVT, 1790 lbs, 516 lb/ft@2800 5 speed stick, Jag IRS 3.54

http://i1236.photobucket.com/albums/ff452/deckofficer/Day%20tripping/DSC013201014x760.jpg

I'm hoping for a better reception here than I received on "Performance Boats Forum", Craig and his spam filters think I'm a spammer. I am a real person, not a spam bot.

[beer30]

Where are you in the US?:) Chuck

[deckofficer]

I'm near Placerville, California and have a vacation residence near Lake Elsinore.

[Bies]

You have fun toys!

[deckofficer]

Thanks Bies, looking for one more, hence my joining this community. What I'm looking for is something like the SVT, very light, like my hot rod, capable of amazing hole shots and 100+ mph. Don't need or want 110 mph or higher, just something that will crack 100. My last luke warm boat was the hemi V-drive flatty in the above picture, good for 85 mph but not for a long time at that speed because something would always break.

[stokernick]

welcome,Bob,we're sure you'll enjoy your stay,retirement is great,let's you hang out on Scream&Fly when there's nothing else to do. Can be addictive,but a good addiction! Nice ''toys''!!!

[deckofficer]

Nick,

Like your boat, kind of what I have in mind. Light, so your not fighting the Laws of Physics, with an ample powered clamp-on. Can you tell me about your fine ride?

[Riverman]

Welcome!

I think you mean STV versus SVT. Here is a STV picture thread.

http://www.screamandfly.com/showthread.php?256452-S-t-v-pic-s

[deckofficer]

Yes Jeff you are correct, as I remove my foot from my mouth. I remember Hot Boats magazine pitted the STV against the current crop of hot boats about 25 years ago and was impressed with its 0~30 mph numbers so much I have remembered it all these years. Thanks for the correction and link to the STVs here on the forum. I hear you are also into electric vehicles, so am I.

[Bies]

Bob,
I have a 1958, 14' Biesmeyer 327 ci, V-Drive

[deckofficer]

Bob,
I have a 1958, 14' Biesmeyer 327 ci, V-Drive

Now that is a classic. Boat of my dreams as a kid each summer at Fallen Leaf Lake.

[Hoss Marine Propellers]

Hello Bob & Welcome to S&F!!!!!
You can't go wrong with a nice STV with a 260, 280 or 300 drag on it.
I'd go with the 260..... 100+ is VERY doable in this combination!

[deckofficer]

Hello Bob & Welcome to S&F!!!!!
You can't go wrong with a nice STV with a 260, 280 or 300 drag on it.
I'd go with the 260..... 100+ is VERY doable in this combination!

That is what I prefer, 101 mph with decent longevity instead of 120+ mph and a lot of wrenching. I wouldn't mind paying the premium for the Verado 350, a 4 strokes quiet operation if I thought an extra 150 lbs hanging on the stern wouldn't mess with good trim.

[Superbender]

Welcome to S&F,for a second there thought you where a Ford fan looking for a SVT,but I see you straighten that up.

[deckofficer]

Jeff straightened me out on that.

[JWTjr.]

Welcome, Bob.

An STV (or pretty much any other lightwer-weight outboard hull) with a Verado would be terrible.

Compared to a 2.5 (any 2.5 EFI/carb) a Verado is about 250 lbs. heavier, not 150--and you're right, that would wreak havoc on handling as well as the boat's longevity.

John

[deckofficer]

John,

Are there any quieter outboards available that could push the STV or other hull to 100? I've heard the hp outboards with above water exhaust, sounds a bit like a screaming 2 stroke dirt bike. And for flexibility to be able to use on restricted lakes like Tahoe, a 4 stroke would be nice. I have a feeling there are no 4 strokes that are light enough with the shaft hp to do the trick.

Input please informed forum members.

[JWTjr.]

A 250 Etec would give you 100, and be quiet as well. It weighs about 100 more pounds than a 2.5. Plenty of guys have rigged 500-lb engines to STVs and have done just fine.

John

[Scmarineperformance]

welcome .Hats off to a merchant marine i was in that program also. the best choice for a quite outboard with a 100mph potential would be an etec 250ho or 300 as well as a merc opti xs 300 both great motors in all aspects

[Largemouthlou]

Welcome aboard,, these guys will steer ya right for sure :cheers:

[deckofficer]

Thanks all. So from what I gather 505 lbs is about the heaviest motor to use while 300 lb "race" motors in the 240 to 280 hp range are what most folks are running.

[JWTjr.]

Two-strokes: 225/250 ETec DFIs, Merc 225/250/300xs DFIs, and Yamaha VMax HPDI engines are all in the 500-525 lb range

Four-strokes: The only hi-performance 4-stroke engine that's even remotely in these engines' league (wieght and performance) is the Yamaha 225 SHO.

John

[JWS]

Bob, Is that your cat blowboat in your pic? We rent one in Tortola occasionally and have a blast with it. Soory guys, I know this is not a blowboat forum. Wecome Bob. I have always sight friendly and helpful.

[deckofficer]

Thanks John. I'll take a look at the Yammie 225 SHO. In my hot rod world, if drivetrain is set up to withstand say 600 hp of a positive displacement blower engine, then that same drivetrain could easily live with about 800 hp output from a centrifugal blower like a turbocharger. With all the cooling median of the water, I can't help but wonder why the outboard manufacturers couldn't build a 250 hp turbo and intercooled 4 stroke in the less than 400 lb range. We do it on land all the time with just air to water intercooling. On the ships I used to serve on, the output of or engine would increase 5000 hp just by operating in water that was 10 degrees cooler. Our engines are very slow turning monsters, producing around 60,000 hp at 118 rpm, but the concept would hold true for small 4 stroke outboards, run a lot of boost and after compression of the intake charge, cool it down with an intercooler for a more dense air charge that more fuel can be added to.

Can anyone tell me why we don't have turbocharged, intercooled, 4 stroke outboards?

[deckofficer]

JWS, yes, it is a Chris White design Atlantic, and for a cruiser is fast. I've seen 21 kt on a reach with friends aboard, so it wasn't white knuckle, hands on the sheets type of sailing. I sold it awhile back, but when time to cruise returns will probably go with another Chris White designed boat.

[deckofficer]

JWTjr,

I liked what I saw with the Yamaha you suggested, 250 hp, quiet 4 stroke at 505 lbs. It does prompt a couple of questions.
1) 20" shaft length, I would have hoped for a 15". Any problems with 20"?
2) Prop selection. Since top hp is reached at 5500 rpm and the gear case is 1.75 to 1, it would appear a pitch of 38" would be needed to break 100 mph. I'm not sure such a coarse screw is even available. Does anyone know? I figured 10% slip.

[warren]

Bob go stv have had multiple with no dissappointments if not go action will b happy there 2 there is a little more driving involved and not quite as fast/good luck and welcome/red rocket out

[JWTjr.]

JWTjr,

I liked what I saw with the Yamaha you suggested, 250 hp, quiet 4 stroke at 505 lbs. It does prompt a couple of questions.
1) 20" shaft length, I would have hoped for a 15". Any problems with 20"?
2) Prop selection. Since top hp is reached at 5500 rpm and the gear case is 1.75 to 1, it would appear a pitch of 38" would be needed to break 100 mph. I'm not sure such a coarse screw is even available. Does anyone know? I figured 10% slip.

The engine rev-limits at just over 6000; you can twist it to 6000 with no problems. There are no other gear ratios available that I know of.

There is also no 15" leg available. 20" is of course taller on the transom but unless you cut it down, there is no other solution.

John

[deckofficer]

Thanks guys. It looks like I won't be able to do my own thing, that is breaking 100 with a 4 stroke, so I guess this at 300 lbs, 8000 rpm is what works and was designed for the task. Shaft length, weight, rpm, and gear ratio ready to go.
http://i1236.photobucket.com/albums/ff452/deckofficer/STV/OptiMax-200XS-ROS.jpg

[JWTjr.]

Great engine. For a smaller lighter boat it will work extremely well. I tested/reported on this engine back in 01 when it was first released; we tested it on a XB-2003 Allison bass boat (20') and it put up some very strong numbers for a "200" horsepower engine (something like 96 mph, don't really remember). The later models are stronger yet.

john

[deckofficer]

Do you know if this is a clean enough 2 stroke not to be banned for Tahoe and surrounding lakes? Some info I've gotten form TARPA, some two strokes are still allowed if injected, they even stated the Optimax was clean enough to be allowed, but they might mean the production version, not this one from Mercury Racing.

[Adam McKeon]

Welcome Bob, I believe this was right up your ally but sold a little while back. I don't think you can beat it personally.
STV's are built local here in Jacksonville FL to suite your needs. Good luck and enjoy S&F.

http://www.screamandfly.com/showthread.php?252269-2010-STV-River-Rocket

[Frank Molé]

welcome aboard,lots of fun here..................