Stock 28 excel How fast?
 

i got a 28 excel with a 330. how fast should this boat go stock and with what prop

Re: Stock 28 excel How fast?
 

What size prop?

Re: Stock 28 excel How fast?
 

23 p mirage 3 blade

Re: Stock 28 excel How fast?
 

63.5mph - I think

Re: Stock 28 excel How fast?
 

That 63mph sounds right, I have one since '91 it now goes 83mph @ Lake Mead Las Vegas.

Re: Stock 28 excel How fast?
 

We need to talk , Whats your set up. I just blew my motor and am looking to build a 700+ Hp motor for her. Here is my current set up http://www.offshoreonly.com/forums/s...d.php?t=139686

Re: Stock 28 excel How fast?
 

'89 stock setup - 59-61 mph with 365 hp.

Re: Stock 28 excel How fast?
 

I guess 63.4 MPH

Re: Stock 28 excel How fast?
 

my 1989 with a 365 ran 62 best avarage 59-60.the 330 would prob be 56-59mph.Mine came with a mirage 23 3 blade turned it 4900rpm.

Re: Stock 28 excel How fast?
 

i have an 88 excel 28 that i recently purchased, and i can only seem to squeeze 64-65 on the gps on lake mead. the motor is supposed to be a 650 hp stroked 454, but i was guessing more like 550... any ideas? im about at my wits end with tuning, and im about ready to start buying parts now. any ideas to get me going in the right direction would be great. id love to find all the "free" horsepower i can before i start building some, such as prop, x dimension, etc... any help you can give would be greatly appreciated!

Re: Stock 28 excel How fast?
 

What prop and RPM?

What elevation you at?

Ck the bottom see if there's a hook in it .Mine had one right were the LH motor mount would be .The motor was pulling up on the stringer on that side.

Re: Stock 28 excel How fast?
 

we need more info like strip said

what is done to the motor. 64 - 65 mph sounds more like a stock 454 mag.

If its a true 550 hp I think you should run some where around 73- 74 mph with the stock X dimension.

if you run the Wong prop on that hull it will ride heavy and scrub speed. Bret at B Blades built me an awesome prop for that hull, that gives bow lift not stern lift like most 4 blade props.

Also the x dimension is very low. around 7 1/2 " :( I have stern jack and a imco 2" shorter drive. it gives me around 4" higher x when I am trimed up. It was the best $$$ I ever spent on the boat.

Re: Stock 28 excel How fast?
 

Paul - did you ever run the 2" shortie without the setback box. Was wondering what the gains were with each mod.

Again - my '89 excel with the 365 mag only saw 61 at best right off the showroom floor. My friend had a "90 23 foot Nova that did about 63 when also brand new. Even after procharging the 454 with 5 lbs boost, it only did 70 MPH (550+ HP). Now with a procharged 540, it's seeing 80 with std length Imco. Unfortunately I ran 1:36 gears with the imco which I'm sure cost a couple MPH.

Re: Stock 28 excel How fast?
 

my x dimension is between 8-8.5". i tt ron at imco last week and he figured it should be in the 5.5-6.5" range? im still pretty new to the whole boat thing so i dont know what a "hook" is. the prop im running is a 26 pitch bravo 1 with a bunch of cupping to it that i bought off of ebay for pretty cheap. i replaced a dinged up 24 pitch bravo 1 with it, but ill have the 24 back this week from the prop shop. the 24 ran between 5400-5600 rpms and went 61 on the gps. the 26 only pulls 4400-4600 but pulls the 64-65 on the gps. i still havent quite figured that one out yet. the guy i bought my boat from was actually introduced to me by my race car machinist, who actually built the motor in this boat. its a stroked 454, to a 496. it has factory square port heads that have been cleaned up a bit. it has a single plane intake, an 850 marine holley, and a comp hydraulic roller that is the 2nd from the largest in the marine lineup. the motor is supposed to be in the 9-9.5:1 range with the je flat tops. im geting ready to but an m4, but like i said in my previos reply, i want to make the boat right first. i know my gimbal ring is a bit sloppy, but only on the swivel pin. im getting ready to do hydraulic steering to clean that up though. hope thats enough info to get me in the right direction, and thanks all in advace for any help you can offer!

Re: Stock 28 excel How fast?
 

Scarab28 Sent you a PM

Re: Stock 28 excel How fast?
 

I also had the 1.36 I belieave it hurt me also

Re: Stock 28 excel How fast?
 

Mine also did around 61-62 new .The first mod I did was Stellings headers dry,merlin heads,ported,MSD,83ocfm Holey carb,1.8 rockers,bobs nose cone,turned a 23 3 blade 5400-5500,speedo said 68 porpoising

Re: Stock 28 excel How fast?
 

Just remember this hull wasnt designed to go very fast.Mine was about 5800lbs. Archer Marine had the same hull which is a 26,no swim platform.A lite race boat ,no inteiror etc.real high X ,Paul Plaff motor, I believe Dan said the best he got was 93mph.

Re: Stock 28 excel How fast?
 

Glenn guy I am finding it hard ti see that you have 550 hp with your set up.

My 454 with 9:1 compression with supercharger at 6 psi boost only pushed 540 real HP not some over compensated dyno results. A lot of guys can play with the dyno #s and make more hp on paper than what you really have. I am not saying thats your case but from the mods you listed done to your engine it sounds similar to the motor my boat had when I got it. the boat pushed a 22 pitch prop at 5300 and ran around 65-67 if I remember correctly.

I would also try and find a stock 24 p bravo prop in order to get a base line to start with. I would not be using a modified prop until you feel how the boat rides with a stock prop. then talk to a professional like B Blades of Throttle up and tell them how the boat is handling. Bret at b blades made me a bow lifting prop and it's the best prop I ever ran. If my memory is correct ( I might be wrong) I thought that extra cupping in a prop gives you more stern lift , But that hull needs bow lift.

Check your hull for a hook or rocker. Get a 4' straight edge. place it on the bottom of the hull from the transom forward. Starting at the botton start dragging it to the chine and look for inconsistanceies in the hull. if it has an area where it seems to sucked in to the boat , that is a hook. if there is an area that bulges out, then thats a rocker. you should see a small hook at the last 1' from the transom, about 1/8", thats there from the factory. You would like the hull to be as straight as passable. I got a 5' piece of oak hand rail from home depot. I glued sand paper to the flat bottom of the rail and used it as a 5' straight edge to sand the bottom of my hull flat. The boat rode more stable at high speed when I was done.

Re: Stock 28 excel How fast?
 

I thought the boat was a bit faster that that from the factory with a 454 mag. .

To answer your question , It wasnt that the 2" shorter drive made the boat any faster , in fact it dont even know the before and after #s. What made me keep it was the ride quality. The wife and I borrowed it from a friend to try. We gave it back just before a poker run.....Very Bad Move.... The ride was so much better with the shorter drive that my wife practically demanded that I get it back when we finished the run.


I will be sure to get all the speed #s with the new motor next season. I want 86 + :evilb: :evilb: :evilb:

Re: Stock 28 excel How fast?
 

hot boat... thanks for the info on the hook and rocker deal, ill check that out this week and see what i come up with. as for the horsepower, it wouldnt surprise me in the least if its down lower than 550. i can only guage from my automotive experience what the motor should make for power. given what the heads flow and the cam and intake combo, i just figured 550 sounded pretty fair, maybe even a bit conservative, but who knows for sure until its on a dyno. im gonna go ahead and do a setback box with a 3" lift and hydraulic steering this month and see what that gives me, but not until after i see what happens with a stock 24. id like to try and max out this baseline before i go changing and adding parts. i also ran a mirage 23 3 blade, but it seemed to be a big waste of time on my boat. i dropped the hammer once i was up on plane( which seemed to take forever to get to) and 5400 came and went pretty quick, then 5600, and ended up at 5650-5700 before i knew it. i made a pretty quick return to the dock after that, but i never thought to pull a gps reading before i pulled the prop. i figured it was just too small. im pretty sure one of the reasons ive been having a hard time getting a better number is the extra weight in the boat and distribution. i almost always have at least a half tank of fuel, and usually a full tank, and always at least have my wife with me and sometimes my kids( maybe 75 lbs between the 2 of them). im gonna try to get out this week by myself with a half or less tank of fuel and finish tuning the motor and check again on the gps. i have my 24 back, and a stock hydromotive 24 to try out. guess ill let you guys know what i come up with!
thanks again for all the info!!! ps my running weight on my boat is 4975 lbs fueled, with nobody on board if that helps.

Re: Stock 28 excel How fast?
 

Ive got a 26 excel with a fresh 454/365 mag with a 420 cam, alpha drive and a 19p wheel. We had an ign advance problem and a run of broken stock rocker arms, so we never got to run it up before tucking it away for the upcoming weather. Ign problem has since been corrected, and its got a set of crane roller rockers on it now. What can I expect for top end, and is this the right prop for the boat?

Re: Stock 28 excel How fast?
 

Gleen guy , keep in mind that all bravo props are one size smaller than they say. example a 24p is really a 23p. A hydromotive is a true pitch, it also a stern lifting prop. They never worked good for my hull. I could never get the speed or rpms that I did as with the bravo 1, and they weren't the best either. A friend gave me some bass boat props to try. They were bow lifting O/B props, Thats how i found out that the boat likes bow lift. Its just hard to find a stern drive 4 blade bow lifting prop unless its modified. and forget about 3 blades . I never had any luck with them.

With the Hydo and a stock B1 the boat rode heavy in the water. The bow would crash into waves so bad that I had people thought that I stuffed it a few times. with my current setup the boat rides on top of the water and lo longer crashes in to waves

You can see from this photo that the boat is running on the pad and riding high.

Re: Stock 28 excel How fast?
 

If you want a nice set up for your 454 . I have my old blower and parts for sale. I have more photos I havent down loaded yet. Its going to be listed on ebay soon.

http://www.offshoreonly.com/esvon/page-13153.html

Re: Stock 28 excel How fast?
 

@ Hot Boat

I have a 28 Excel with a 502 EFI it´s running 67 mls but at Top speed the Hull is to the half in the water. I have a 24 P Bravo that realy was only 22 P it is pressed to 21 Pitch an had a swissmade labfinish.
I have the same problem that the Boat goes very hard thru waves ( thats the reason why i look for Stand up Bolsters).
We drive mostly on the River Rhein and sometimes there are a lot of short but high waves. What kind of Prop do you have and what was the modifikation

greetings

Hans

Re: Stock 28 excel How fast?
 

My prop is a re pitched modified labed finished Bravo 1 by Bret @ B Blades

Re: Stock 28 excel How fast?
 

@ Hot Boat

Thanks for helping , i want to upgrade my EFI after this i surely have to change the prop. I will try to get one from B Blades because i think youre realy right with driving " on " the Water

Greetings

Hans

scarab true speed
 

I have a 1987 scarab 26excel which is the same hull as the scarab 28 but with a different deck and is about 100lbs lighter.
It has the 330HP Alpha 1 1.34gear ratio 21P 3 blade prop. The boat runs 52mph.
A friend before his divorce had a 28excel with a 502 415HP
Bravo 1 23P prop and he was hitting around 60mph.

Your gear ratio is hurting you.

28 excel prop
 

I share your frustration with the prop. I just completed installation in my 1987 28 excel and I am getting close to figuring my boat prop situation out.

My specs are accurate with dyno sheets from Derryberry racing which they installed the motor and performed the tests with as well. boat was with two full size adults and nearly full tank of gas.

540 cubic inch Merilin
1050 dominator
Custom made twin wall tuned headers
MSD limiter set at 5800 rpm
629 horsepower at 5600 rpm
Bravo one xd

bravo one 4 blade 22p gave on gps 67.8 mph at 5800 limit
52 mph at 4200 rpm and 60 mph at 5050 rpm

bravo one 4 blade stock 24p on loan yielded exactly 70.0 mph
at 5450 rpm

next was a 28p and the boat and engine could not pull it

My last to try is going to be a labed bravo one 26p and I hope to pull 72-73 mph at about 5300 rpm.

If anyone has a different suggestion or idea please inform me as any input is of value to me.

does anyone know what it takes to put a portapotty in a 28?
Oh by the way the boat is run at lake texoma in Texas and all tests were in weather between 65 and 75 degrees in April 2007

sincerely
Tom G

Mine came with a porta and it was in the front center compartment, you couldnt use it in there ya had to pull it out to use it.

If the 4 blade stock 24p on loan yielded exactly 70.0 mph
at 5450 rpm. I would think a labed to 23 would get ya back up to 5600.