Small un seen little things...:)
 

My dad wont let me re do the 4.3 so Im looking for a few more mph, anyone know any small un noticeable (looks wise) things like a new flame arrestor (will that help?) just for a few mph more....

4.3l 262
carbed

From my experiences with boats, "small-unnoticable" changes net small-unnoticable results. In performance boating, there is no free lunch. If you want to see some gains in speed, it`s gonna cost you, especially with a 4.3. To be satisfied, you probably should sell your boat and step up to a V8.

Just my opinion.........

Yup.

one problem, its my parents boat. Whats the new 5.0 vortec's selling for?

Dear Hyperbaja,
Been there, done that, but it was a long time ago!

Install a straight tube instead of the bellows in the exhaust system in the outer transom plate. Little noisier but less backpressure (talk to a merc mechanic he will know what I'm talking about).

Advance the ignition timing two degrees past stock (buy a timing light, learn how to use it, and time the engine to the stock specs in the book plus 2 additional degrees advance).

Install extended tip spark plugs with a larger plug gap (get a plug catalog and study it to understand the differences between standard and extended tip plugs).

Rejet the carb for the type of altitude and weather you generally use the boat (buy a book on carburetors and study it).

Buy a book on props and understand the relationship between engine rpm and pitch and then send the prop out to a prop shop and have it reworked.

Once you make the effort to make these mods you will have learned more than the average boater and will have a better running boat.
Sorry it isn't any easier than that but learning about this stuff is the key to going fast!

Sincerely
Dennis Moore
FAMILY AND PERFORMANCE BOATING MAGAZINE

Noticeable performance gain from engine power alone requires significant changes. Those appear to be "out" in your case.

On a 20-ish footer, any change towards rearward weight bias will increase speed. I am assuming that your current topspeed is attained using positive trim (trimming past "neutral"). This shows that your hull/weight bias responds favorably to lifting the bow.

Moving any heavy item from the front to the rear will make it easier to lift the bow. Moving anchors to the stern, moving batteries back a few more inches, storing your cooler under a rear jumpseat, etc.. These will all give you either More bow lift at a given trim angle OR the same bow lift at a LESSER trim angle - both will net a speed increase.

Using a prop with bow lift (3-blade Mirage Plus) over a prop with minimal bow lift (Hydromotive) may be your best bet. On the other hand, it is possible that your boat will like stern lift instead (although I would be surprised).

A clean hull is a must.
Keeping the boat light is helpful (don't store a whole weekend worth of stuff if you're looking for speed).

Beyond that, it starts to cost money and becomes visible to the parents....

good luck

(nitrous can be hidden easily)

Nitrous.... :D
Clean hull--bottom paint with primer which parents wont let me take off....

Prop-3 blade 14x19 turbo stainless.
i gotta try some new props next year...

I did a "back to back" with a 21" Turbo and a 21" LaserII and found the Laser had significantly more bow lift. This was on a 22' Crownline with a 5.7Alpha

I ran a Turbo 2+2 4 blade on a 20 ft Mariah with a 5.7 260hp. and was not impressed with it's performance.
Since then I've been told that Turbo makes a great bass boat prop but a marginal I/O prop.
Call the MFG. of your boat with all of your numbers and tell them what you are wanting to accomplish. They should be able to help.
I have a friend that did that through his dealer and they came back with the VENGENCE three blade.
Smaller diameter and more pitch than his original prop.
Normally the only way he could get the speedo even close to the top of the speedo was empty on fuel and by himself.
With the VENGENCE 3 bl. he was able to PEG the speedo (not just get close to the numbers) past the numbers with 1/2 tank of gas with 1 other person with him.
In a nut shell--------GET ANOTHER PROP will be the biggest change you will be able to make, and maybe not get busted by Dad. If you play your cards right he might even go along with you, once he sees the difference.
Be verrrrry careful on asking for good top end and expecting a good holeshot for skiing. It's not going to happen!!!!!!!
On the other hand you could own 2 props. One for you and one for the "Family"
GOOD LUCK

Hey kid,
You better do something with my $10..or should I say yours now:D
Opies right the right prop is probably the cheapest speed your going to find.
I had great luck with Ballistic. They're stainless and come from the factory with a thinner blade , almost like being labbed but 1/3 the cost. New your talking about $300.
Still believe in Santa?:D :D :D Christmas is coming. This Santa has to get his kid a set of 12.50x33 Michelins:rolleyes:

Id be lucky to even get those in to the powerband!!

Re: Small un seen little things...:)
 

Let's face it...........you're tryin to hit 50 right (you goin 46 now ?)? ;-)

I'll be honest with ya, those 10 mph marks are hard to hit.........it's liek a wall. You get to the x8 or x9 mph mark before the wall, then it's a major pain to hit x0. LOL

Maybe you want to just start building small block........then when you're done, start it in the driveway, and let your dad hear it - lol.

Deep down inside, most guys, even if they don't show it is that yearning for "MORE POWER" You just gotta throw a little gase on that hidden flame ?

Besiders if you are able to pull this off, one other advantage is that you can freshen up the 4.3 & when you go to sell the boat, you'll have a fresh engine for it.

In any case, you'll have to do a significant amount to see a noticepable difference. But beware, don't forget if you do build a v8, you have to consider the added wt & fuel economy, if it's a big concern. (Before I got my first boat I was looking at some 19-21 foot fiberglass boats. I know going from a 4.3 to a 5.0 (v8) there was aboput a 3 mph gain, but fuel econmy was quite a bit worse)

Please excuse my sh*tty grammar / spelling this wonderful morning........we ran out of normal coffee. I'm runnin on decaf - lol

Re: Small un seen little things...:)
 

Hyper... Can you spell N.O.S. Ran nitrous on a 20 Baja S/B with unreal results for 7 yrs with no problems. After the first year I did some changes such as cam, intake, can't remember everything, but it ran a solid 80 on good water.

This is easy, drill the speedo hole out from 3/16th to 1/8th and that shoud do it.


Hopefully someone laughs when they read this......

You sell boats ? lol :D

Isn't it difficult to drill out a hole from 3/16 to 1/8 ? Where can I find me one of these magical drills ?

:confused: :) :D

Thats what i sould do, start building a small block. Can someone start me off with some places to start at? Jegs is only a 20 minute drive away from here....:)

YEAH!!!!!!!!!!! I WORKED MAGIC ON HIM, Dad says i can put it in on one condition, I put a new drive on it because he dosent want me to blow it out (In otherwords, he dosent want to learn how to throttle the boat correctly)

So, how hard would it be for an alpah to bravo or arneson swap??
Or should i go with an alpha SS?

heres the engine-
http://www.1800runsnew.com/gm04.htm

And yes the flywheel and mounts from the boat will take the 350ci, it was an option back in 1990. :D

Just stick with your Alpha. It will work fine on your light boat unless you plan on putting 500 or so HP to it.

Yeah , Hyp
A friend of mine has a 20' Rinker with a 406 small block and an Alpha. Been running it two years now and no problems:rolleyes:
And this guy isn't easy on it...I wouldn't run it as hard as he does:cool:
The original MERC 350 MAGNUM (260 HP) did 58 mph , changed to 325 hp Vortec crate motor and got 64/65 but didn't have the holeshot of the 260 because he bought a GM engine that specified "not for highway or marine use" . Marine cams are different:eek: Then went to a 406 sb . Dynoed 390 hp and over 400 ft lbs torque. This got him in the upper 60's.

Good luck Bud.

tssteph
I laughed. I like your thinking. Heck for that matter put a blown 540 in it... REDUCE the intake on the speedo,,, and tell dad it's just his imagination, the boat runs the same as it did last year, You just don't remember cause your getting old.

No need, got the ok.... Itll be a lot quicker this next summer. Maybe if the local with the 29 baja with twins learns how to drive a little better we can have a competitive race, this year i blew him away... He dosent seem to know that to go faster, the props need to be in the water.... Some people.

if your gonna put a small block in it,
you may wan't to switch to a
1.50 ratio, or a 1.47 ratio drive,
V-6's usually came witn a 1.84
ratio drive, and as far as i can
remember, all gear ratio changes
in alpha drives are in the upper
unit, gear ratio's are usually stamped
on the decal on l/h side of upper
gearcase.
you can leave the same drive on,
but you WILL have to buy a MUCH
LARGER prop than you are currently
running, and you will have to
GO EASY ON IT.
good luck,
jt

get yourself a PAW catalog (performance automotive wholesale). you can order it off the net.

They have every kind of engine kit combo known to mankind.

If $$ is an issue, you will obviously be going with a 350 Chevy or maybe a 400 smallblock (they won't be more than a hundred $$ apart). You can get a complete kit with a ready-to-go block all rustoleumed up inside and choose your parts.

A "stock" 350 chev with a decent dualplane and a 650 holley and a marine cam will give you around 280hp. Your drive will handle this just fine.

The 400 smallblock can make 310 inexpensive hp (stock heads, dual plane intake, hydraulic cam).

Keep WOT rpm under 5000 and everything will be happy.

NOW, you will need a V8 oil cooler.
you will need V8 exhaust manifolds (Dennis Moore wrote an article on some aftermarket ones that were cheaper than stock and performed better than stock - can't recall who made em but look up Dennis' profile and chase down that thread..)
Oil pan, Intake, Carb, distributor...

You can use your T-bolt module, alternator, raw pump, ps pump, etc...

This is getting exciting...

www.1800runsnew.com

the GM
The 350
325cshp

will need exhaust, fuel pump, oil cooler

drive now is 1.84 so that needs to be a 1.5, whats that cost to switch from 1.84 to 1.5?

props, what range should i try first?

If it were me I would leave the 1.84 and get a different prop. With that ratio if you spin a 26 pitch prop between 5000 and 5200 RPM you should be knocking on the door of 60 MPH. You are getting into a pretty big project. Are the motor mounts on the v6 the same as the v8? How about space in the engine compartment? Just throwing some questions at ya. There are a lot of horror stories out there of guys trying to get a little more and ending up not boating because of these type of problems. ;)

The boat had the option of the 5.7 back when it was built, same mounts, flywheel and the same amount of under hatch room.

You already know you need a prop.

While there are several reasons to "choose" a specific gear ratio if you are buying a lower unit, you already have one, and it is giving you no trouble.

The vertical shaft and lower gears in the drive will be subject to more torque at 1.84:1 than it would be at 1.5:1 (23% more torque). An Alpha expert would need to assist you in making the right call as far as how close to the line you are at 325hp (360 ft.lbs of torque).

If you are within the safe zone for the drive, then you can figure that @ 1.84:1 and 4900 rpm, to run 63 you will need a 28 pitch prop. At 1.5:1 and all else the same, you need a 22 or 23.

** I think you should forget about marine exhaust manifolds and just get some truck pulling headers and let them stick straight up out of the engine hatch. Your dad will love it.

ya or do it like Tim's 28 Skater with the jet boat headers. Charlie

I posted before I saw Tim's picture in the other thread.
They must be more lenient about exploding boats and stuff in Turkey...

Tim, please always use your bilge blowers with those redhot rewarders (they do make you have bilge blowers over there dont they?).