Spectra 1977 20'?

[pw_Tony]

Hey I got a Spectra 20' Daycruiser and I need some speed. It's got a 460BBF and I'm throwing a 6-71 on top of it but it's got a little pussy cam, like a .450 lift but I can't go bigger unless shortening the guides. I was expecting about 7lbs of boost, it's got all stock heads and I'm finding some headers for it. Just got aplace diverter and I'm lookin for what kind of speed or horsepower I'd be getting. The boat weighs with motor 2500 lbs but it rides pretty shallow in the water. Anyone got some ideas of speed or how to get more? Thanks

[El Prosecutor]

I was reading the other day that some of the Spectras get a little squirrely at speed. Not sure if that applies to the 20 though.

[FASTJTBT]

That boat should run well with that motor mid 70s at least that hull is a soild built boat very heavy. As for the way it handles will be fine they run on the keel not much lift.My 19 will run around 110 and thats about it and would want to drive it any faster.Around 92mph to about 100 the boat handles real well I tow a skier in that range works nice. Good luck

[malcolm]

I was reading the other day that some of the Spectras get a little squirrely at speed. Not sure if that applies to the 20 though.
I think they were refering to the 18s. Mine doesn't get that way unless I'm running wide open in rough water, but then wouldn't any? ;)

[pw_Tony]

A spectra that does 110? Wow what you got done to yours? I still wonder what kind of horse I'm lookin at with a pretty stock 460bbf and a 6-71 runnin bout 5 lbs of boost?

[Boatcop]

If you're going to be boosting the HP, I'd consider installing full length stringers, if it doesn't already have them. The '77 20' only had the engine box.
You could also spec the bottom. Even though hook issues apply mostly to flat bottoms, or semi-vees, bottom irregularities can also affect the top speed on modified vees, like the Spectra.

[pw_Tony]

What are full length stringers? And what does riding on the keel mean? Sorry I'm kinda new to this...

[Boatcop]

What are full length stringers? And what does riding on the keel mean? Sorry I'm kinda new to this...
Older Spectra 20' jet boats and all V-drives have stringers that run along the inside of the hull to add rigidity to the boat. They reduced the jets in later years (1974 and up, I believe) to just having short stringers around the engine. Maybe to save weight. Maybe to save money. I don't know. I do know that on mine I can feel the hull flex in heavy wakes.
Riding the keel means that at speed, the boat lifts out of the water where just the keel is in contact with the water. This makes the boat pretty unstable in smooth water. In rough water it doesn't really apply since the waves/wakes are contacting a greater surface of the hull.

[pw_Tony]

You're boats pretty sweet lookin, what kind of power/mph are you runnin?

[hack job]

it could be possible that the 20 has full lenght stringers due to the fact that it was a option after 75 but most likely it is a goal post deal. one stringer down the middle of the boat . and a floor for strength.;)

[pw_Tony]

I'm hoping for about 550 hp, maybe but I'm not sure that's why I started this thred, but should I add support? The boat seems really strong and heavy but I honoestly dont know how strong?

[Boatcop]

You're boats pretty sweet lookin, what kind of power/mph are you runnin?
If you're meaning mine, it's pretty much a stock Hardin Olds w/ Torker and 750 Holley turning a Jac WJ place diverter and 6 degree wedge.
No numbers on it since I put the manifold / 750 / diverter & wedge on it. Before that I'd be lucky if I was hitting low-mid 50s.
The add-ons might give me another 5 MPH.

[pw_Tony]

That's sweet. I think mine pulls about 53-55 mph. I live in Bullhead. I haven't driven the boat that much maybe like 50 miles, what do you feel are the strengths and weaknesses of these big boats?

[Boatcop]

That's sweet. I think mine pulls about 53-55 mph. I live in Bullhead. I haven't driven the boat that much maybe like 50 miles, what do you feel are the strengths and weaknesses of these big boats?
The Spectra's biggest strength is the hull design. It is probably the smoothest riding boat of that era. It's also the most splashed hull design ever. Tahiti, Hallet, Bahner, Southwind, Omega, etc.... If you can name a Southern California boat builder of the '70s and '80s, chances are they splashed the Spectra.
It's also the quality of the build. They were all built to last, and the number of them around today is a tribute to Ed and Bud's design and workmanship.
If there is a weakness, I'd have to say it's weight. It's a pretty heavy boat. Other than that, I haven't been able to find one. For a family cruiser, race boat, or sandbar junky, you can't beat it.
We ran them out here and on the coast in the mid '70s - early '80s with the Coast Guard. That was my first exposure to Spectras, and after doing that for 3 years, I just knew that I'd own one someday.
There's a Spectra (http://www.spectramarine.com) website that can give you all the info you need on these things, and a few there that may even be able to tell you about YOUR boat.

[pw_Tony]

Splashed? Another new term that I dont know

[Oldsquirt]

Splashed? Another new term that I dont know
Splashed = copied.

[flat broke]

Just to be clear, a Spectra 20 with a jet does NOT ride up on the keel unless some substantial work has been done on the bottom. The inner strakes stop up around the drivers seat, so there is nothing to lift the boat up onto the keel from there back. Trust me, after having a 468, then a twin turbo intercooled 468, then an 821 hp N/A deal in front of the jet in one, I've done my share of tinkering on them. No matter how much shoe/plate/droop/wedge you throw at that boat, the ass likes to stick to the water because of the weight and the lack of lift built into the hull back there. That same trait makes the boat super predictable and compatible with both V'drive and I/O propulsion setups in addition to the jet. As for 500-600hp in that boat as a jet, you're probably looking high 60s with proper setup. You aren't going to build a Porsche slayer out of a Vista Cruiser wagon. Enjoy the hull for what it is, and it's positive attributes. If you want to haul ass, and want to do it in a Spectra 20 with a jet, be prepared to build a stout mill, and flip the boat over to do some modifications to the bottom.
They're great boats and I love em to death, but you have to be realistic about what you want out of em performance wise, and the lengths you're willing to go to in order to achieve those goals. Merely bolting stuff on without a master plan definitely isn't the most efficent way to make a Spectra or any other boat haul the mail.
Good luck with it, and be sure to check out Brent's website at http://www.spectramarine.com I owe a lot of what I know about Spectras to Brent's undying love for em, and his willingness to share information.
Chris

[pw_Tony]

Well we'll see won't we lol? Mine does bout55 right now wit a 340hp motor. Yea it's a heavy boat but wit a dicent amount of boost it should break 70, not really lookin for 95mph or anything but it seems to ride pretty damn far out of the water from some pics I have. But thanks for the advice It's still a wonder to me.

[malcolm]

You may want to get a GPS number on that boat before and after just so you know what is really happening. Just a little boost isn't going to get that cruiser up to 70. I really doubt it's doing 55 now. I've got 390 horse in my 18 footer and it's only seen 55 once. I figured I'd have been way over 60 by now. ;) That boat is capable, but it's gonna take a lot of HP to do it.

[Riverkid]

A spectra that does 110? Wow what you got done to yours? I still wonder what kind of horse I'm lookin at with a pretty stock 460bbf and a 6-71 runnin bout 5 lbs of boost?
BAM!
http://www.***boat.com/forums/attachment.php?attachmentid=23940&stc=1&d=1171210402

[El Prosecutor]

Anybody have any specific experience or thoughts on the 19' model 190?
What would it take to make it go 70? Handling characteristics?
I am thinking about buying this boat as a project:
http://c.im.craigslist.org/ov/GN/7l4YieqGj9agAmE4a4lBqfK7FCKf.jpg
Yeah, I know - the seats have got to go. : )

[FASTJTBT]

Thanks for the photo. That motor is for sale I really want that new nordic by this summer.

[hack job]

Anybody have any specific experience or thoughts on the 19' model 190?
What would it take to make it go 70? Handling characteristics?
I am thinking about buying this boat as a project:
http://c.im.craigslist.org/ov/GN/7l4YieqGj9agAmE4a4lBqfK7FCKf.jpg
Yeah, I know - the seats have got to go. : )
i had a 19 that i got to 90 with 740 hp on the first trip out( no set up work done). with a pretty easy built motor ( small cam and logs)i got 75 out of it. i loved that boat it was awesome i sold it after i had some issues with the gel coat( had been redone very poorly).

[v-drive]

i had a 19 that i got to 90 with 740 hp on the first trip out( no set up work done). with a pretty easy built motor ( small cam and logs)i got 75 out of it. i loved that boat it was awesome i sold it after i had some issues with the gel coat( had been redone very poorly).
BTO's dad here. what ever happened to that boat. My son is still chasing cracks. next winter he is going to grind the whole top off and re-do his.
v-drive:(

[pw_Tony]

Well I gps my already, isn't that the first thing a hot rod boat guy should do? It hit 53mph with people and almost a full tank of gas so I just assumed it does 54 or 55. But then again it is a weak ass ford motor in a big heavy boat so I guess I'm just crossing my fingers for 70mph with some boost, even though I don't know what kind of power it would put out altogether. And yes it's true you can't make a big cadillac go faster no matter what. That's why I'm lookin for tunnel hull shallow boat so I can drop my 440 in it and push some numbers.

[malcolm]

Most likely scenario is you'll put some boost on it and hit 57. ;) It takes major changes to get that big a jump in speed.

[pw_Tony]

Well let's see I do bout 53-55 right now, pretty much stock. And I should get only to 57 with over 550 hp? I dunno bout that

[malcolm]

Last I heard you were going to put a conservative blower setup on a stock 460, how's that going to make 550hp? I'm not trying to burst your bubble, just giving you a little taste of what I've found out over the years with my smaller Spectra. They are nice boats, but they do require gobs of HP to go fast. I started out with a stock small block 200 hp motor. Got me up to 44 mph. I jazzed it up to around 350 hp, that got me up to 51. Now with a big block making around 400 hp, it's gone 55 once. :) I'll be the first one to jump up and down with ya if you can make that thing do 70, but I thought I'd have passed 60 a long time ago. :D

[pw_Tony]

Well I'm not lookin for a race boat I'm just hoping for 70+ "hoping" is the key. Who knows what it would actually do. I've only tinkered with another jet boat and we pulled 65 mph wit gps out of the thing with a 396 BBC, granted it was 1000 pounds lighter. But with a 6-71 witha decent cam and heads should pull 550hp no problem. I just built a 340 dodge that pulled 560hp on the dyno and it had a dual plane intake and some eldy heads and that's it. But if this 460 can't pull 550 with 7lbs of boost and a decent cam then I should just go out to the river and sink it and buy a BBC boat or a dodge.

[flat broke]

No one here is trying to burst your bubble or crap in your coffee. It's just that a few of us have quite literally been there and done that. The comments that have been made have only been done so to adjust your expectation or "hopes" to a very well documented reality. I wish you the best of luck, but also woudln't want someone laboring under the delusion that 500 or so hp in a Spectra 20 with a jet will be a guaranteed ticket to the 70s... unless of course you're talking the styling of the boat :) Keep us posted, and feel free to post up some pics of your ride. I love seeing Spectra pics, so the more the merrier.
Chris

[pw_Tony]

Well that is the truth of it. I'm just gonna have to finish and run it and see what she pulls. The other 20' Spectra guy on here said I'd probably pull mid 70's but I don't know about that, it's a big boat lol. But Maybe but maybe not. Ford's aren't really my thing anyway, it's just what I got.

[Schiada Time]

Don't knock the Ford so quick. They can be built to perform awesome as I had a 501 BBF in my old '19 Hallett and with a set-up pump and blue printed bottom she ran 78. With the motor bored .030 over, aluminum heads from Edelbrock, an Eagle stroker crank, JE 9.6 :1 pistons (pump gas friendly), mild Lunati cam, Weiand tunnel ram with two 600's this motor made 533 HP and 599 TQ. Torque is key in a jet boat getting the power to the water. The pump is like a transmission in a car so you need to detail the bowl, do a blueprint, add a droop snoot, place diverter, loader grate. Is the pump a 12 JC? If so I would have the split bowl conversion done or find a 12JG. The cool thing about a 12 JC is it has longer veins. Good luck.

[pw_Tony]

That's a crap load of torque. What kind of weight is was your 19' lookin at?

[pw_Tony]

I was checking out www.spectramarine.com and alot of their 20' seem to be running good numbers, but the key is I'm running budget so that takes 7mph off right there haha. What other kind of speed tricks are there? I'm still new but I heard about a drop snout and a special grate or something, anyone?

[Squirtcha?]

No one here is trying to burst your bubble or crap in your coffee. It's just that a few of us have quite literally been there and done that. The comments that have been made have only been done so to adjust your expectation or "hopes" to a very well documented reality. I wish you the best of luck, but also woudln't want someone laboring under the delusion that 500 or so hp in a Spectra 20 with a jet will be a guaranteed ticket to the 70s... unless of course you're talking the styling of the boat :) Keep us posted, and feel free to post up some pics of your ride. I love seeing Spectra pics, so the more the merrier.
Chris
Well said Chris..............per usual.

[CampbellCarl]

Two words.........."Day", as in, not an overnighter and "Cruiser", as in, not a racer!
Carl

[spectras only]

The 20 Spectra is 2550 lbs dry . Take yours to a scale , and I guarantee it will top to 3000 lbs. The thickness of the hull is nearly 1" at the keel , and the rest of the hull is pretty stout . If you look at the length , width and freeboard ratio , this is a heavy 20'10" hull compared to other 20' boats . Without a trim device [ place diverter ] the boat runs level , that's causing the hull run wet [ too much surface drag ] . The boat flies level when airborne [ it's a good thing] because of the CG . My 19' & 24' V-drive flew level too . The 20' is perfect for jet application [ 12 degree deadrise ] , but perform much better with a sbc sterndrive , compared to a BBC/BBF with a jet . Best speed would be attainable with two 250 HP outboards ;) . A stock 460 will give you an honest 55 mph , and around 63 mph with roughly 500HP . My best was 72 with a 500hp BBF on the 19' Spectra ,that's more of a performance hull .
Here's a vid of my 20 with a 429 BBF >
http://media.putfile.com/My-old-1976-20-spectra-jet--429-BBF
video of my 24 with an LS-6 BBC >
http://media.putfile.com/24-Spectra-at-Jericho-beach-Vancouver
http://media.putfile.com/24-Spectra-in-English-Bay-2006-July-22
My son driving the 19 , 429 BBF >
http://media.putfile.com/Adrian-driving-the-19-spectra

[pw_Tony]

Well there's some facts for me to smoke too haha. Well I'll do what I can but daycruisers aren't fast. But is there any other secrets for a little speed? I got a place diverter I'm just lookin for a couple other goodies to get it out of the water.

[superdave013]

Well there's some facts for me to smoke too haha. Well I'll do what I can but daycruisers aren't fast.
nope, no fast daycruisers. ;)
http://www.hotboatpics.com/pics/data/500/1503IMG_0559.jpg

[pw_Tony]

Hey superdave So what's the stat on your "slow" daycruiser?

[superdave013]

That's not my boat but is me driving it.
It's the Short Bus and it hauls azz big time. But it does live up to the name DAY cruiser because it's always on kill and at the end of the day it's gonna need some new parts. lol
It's a v drive, not a jet. The rougher the water the better for that boat.

[Schiada Time]

It's a v drive, not a jet as posted by Superdave
A v-drive cruiser can move with good gearing and ample HP-getting a jet cruiser to haul ass is going to take some big HP, a lot of set-up work etc. I'm not saying it can't be done but be prepared to spend. My old 19 Hallett probably wieghed in the 1,400 pound range (hull only) and I would say about 3,000 complete.