Chinewalking
 

Hey Guys, I could use some info about an '88 steve stepp velocity that I purchased. I have an '88 22' steve stepp velocity hull that I just purchased with a 454 and 7.4 alpha drive. The engine was blown so I rebuilt it. Bored it .30 over with mild cam. Engine has 450hp and I replaced the drive with a 1.50 Bravo 1 drive. I have a 23p mirage prop on it. I can get around 5000-5100 rpms as max. Problem is I'm only getting about 62 mph out of the boat and I was told the boat should be faster. The other problem is right around 61 mph the boat chinewalks violently and the ass end begins to slide. I can't get it past 60-61mph without the chinewalking. I was looking at doing more work to the boat and motor to get faster speeds but I need to correct this chinewalking first. Does anyone have any ideas of what it could be and/or how to fix it? Does that top end speed sound about right also or is something off? Thanks

If the engine is putting out 450 hp you should be spinning at least a 25 or 26 inch prop. My 23 (Regal) Velocity ran a 25 inch Mirage with a stock 454 mag with headers. Topped at 70/71 mph with light load and chop. Is there a rev limiter on the engine? You may me up against it.

The Alpha drive is not going to last with that power. Upgrade to a Bravo and add external steering to help with chine walking.

Brade he did the bravo upgrade he just bought it with the alpha. Agree on the Hydra steering all velo's need it but need to get that up on the pad, thats where they fly.
-Mike

is the X the same depth as the Alpha if so good. i have never seen one of these boats work right with w 3 blade prop and yes a 25 should be close i would try a 25 hydromotive also make sure there is no side to side play in the drive, if there is you have something in the steering loose.

Thanks guys....I may try the 4 blade, I was thinking about a 25p but thought with the engine running around 5100 rpm's with the 23p if I went to the25p I would be working the engine more than it should. Machine shop said 5200 rpm's are max for this engine. I was thinking about putting trim tabs on the boat. The boat just gets real squirly @ 60 mph. The drive is tight, no play

The 23 (Regal) Velocity ran faster with the three blade Mirage. I don't know if the 22's do although I would think they would be lighter in the bow and might like a hydro better.

Is there a rev limiter on the motor?

I don't believe there is a rev limiter. I was told the boat should easily reach 70mph with my set up. But I'm only reaching about 62mph @ 5100 rpms but like I said as soon as I reach about 60mph the boat starts to porpoise and chinewalk bad. I try to correct it and the ass end starts to side

That hull should run 70 mph ! Something is wrong . Are you sure that is a 1:50 gear ratio in that drive?

24 Tempest Plus

Your pad bottom won't like 4 blades; more blades = more stern lift. Let the pad hull do what it was designed to do.

Tempest Plus has a smaller diameter than your M+ which is why you can go up in pitch.

I'm pretty sure. I bought the drive used and was told it was. My mechanic opened it up and resealed everything. I wasn't told otherwise. I do know the person I bought it from was another mechanic and had 1.36 bravo drives as well for sale. But he told me it was 1.50

1 Make sure you have a 1:50 gear ratio,not a 1:36 gear ratio in that drive.
2 If 1:50,try a 25" pitch prop
3 Have someone hold the steering wheel and see if any play in that drive
4 check for rev limiter
5 check bottom of boat for rocker or delamination

Ok blackboat, I will. Thanks

If you are chine walking, you are probably not getting up on the pad well. You need enough speed and you need to lift the nose to force the pressure onto the back end of the pad. Are you trimming the drive out as far as you can? Hydromotive sells both versions of prop--both bow lift and more neutral/stern lift. You want the "X" version of their props if you want bow lift--that would be a Quad IV-X for their four blade.
I run their P5-X five blade on my 290SC and it lifts the bow up and takes away chine walk--was a massive improvement over a Bravo four blade. The rest was that I had to trim the drive out as far as possible to lift the nose before the chine walking can set in.

I think there might be a problem with the bottom as suggested earlier. I had a boat that did the exact same thing, a fiberglass repair place solved it by "removing the hook" in the hull.

I'm still not sure exactly what they did, but they got it right.

I also tryed different props, but it didnt change anything.

your on crack, everyone i know is running a 4 blade on velocities some of us have tried 5 blades and they can make the boat handle better Mark this ain't no fish boat:lolhit::kiss:

Pipe down pipe head...

4 & 5 blades on a 22 footer?

Oscillations start because it is falling off the pad. Big words make it look like I know what I am talking about, don't hurt yourself! Anyway, great hull- just have to let it do what it is designed to do and then push the boat forward. Less blades, less drag. Less diameter, more pitch and prop torque is a bonus. Higher rake will bring the slip down and 70MPH here we come!

my 280 did not want to get on plain with a 3 blade , i was at a frinds shop yesterday putting my boat up ,he has a 23 and runs a 4 blade hydro

I tend to agree with you. I was thinking a Laser II would work better also. On 22ft and less, a three blade seems to work very well. My boat is a pad bottom also. I picked up roughly 8mph going from a 21p M+ to a 23p LaserII at the same rpm but I lost ALOT of cruising efficiency (worse gas mileage). I'm thinking a 25p LaserII would be what he's looking for.

numb nutz i bet you could not even drive a pad bottom boat:evilb::kiss:

If it dose all this at only 60 either the X is too low or you have a problem with the bottom.

vel22, have someone take a picture or video from a dock or another boat. Here's a pic of my boat. If it looks like this, you're running on your pad...
http://img.photobucket.com/albums/v7...e/Doinwork.jpg

Thanks guys for all the info. I'm gonna doing a few things including going to a 25p prop. I was talking to a few local guys here and I think the problem is I didn't have it trimmed out enough to get it on the pad. This is a new boat to me and not used to the pad bottom.

Good luck with your 22 velocity. They are awesome boats ,and yes they do take some seat time to get used to them !

You may well be correct. My first Velocity was a 260 (24') and I was a bit frustrated at first with the speed. I was trimming it like any other boat I had owned. Once I figured it out, I went from low 60's to over 70. If you are truely putting out 450 HP, then it sounds as though the boat is not trimmed enough given the RPM you are getting with a 23 pitch prop. You should be able to run a 25 pitch 4 blade with no problem into the 70's. The correct prop will make a huge difference on bow lift or stern lift, thus speed and handling.

I think a bravo drive is longer than an alpha. If you didn't raise it you may be too deep with the prop shaft. Try a smaller dia 4 blade prop/. The Merc revolution 4 might work better than B1s or QIVs.

Pat i thought the same thing but a guy here that has do some of the up fits says no they are the same

Rev 4 is the 4 blade version of the 3 blade Tempest Plus, good choice but still think a 3 blade would be best for a 22.

4 blade? Thinner blades and smaller diameter of an Enertia might be the ticket.

I ran the Rev 4 on my 24' Superboat. It is the 4 blade version of a Mirage plus, 14.5 dia. vs 15.25 dia for the B1. The Rev 4 works well deep like the Mirage and Mirage plus. The prop shaft on my 24' Super was 5" below the bottom. The Rev 4 was the best stock prop I ran on that boat.
I like the B1 on my 26'/280 Velocity for all around perf.

I run an 86 Velocity. Has a 406 (~600hp)small block Alpha drive. Run a Hydro QIV 26p+1"(27p) and hit 88-90mph @ 5700-5800rpm. It doesn't have any walk till the mid 80's and trim usually takes it out. I'm betting you aren't getting on the pad too good. I tried a 3 blade Mirage 23p and it sucked on this boat... You should run at least low 70's with a mild big block. Check the bottom and maybe try a 24-26p Hyrdomotive Quad IV. This pic is ~75mph at 5000-5100rpm cruisin.. http://i250.photobucket.com/albums/g...vo/lake051.jpg

Nice Boat!
DKerns and I almost worked a deal last year.
That Alpha you have must be the strongest ever built.

I love this boat. He had mentioned something about someone else interested if I wasn't going to be able to swing the deal.
That Alpha drive is about wore out. It has a lot of in/out play in the lower. I've got a spare in the garage I'll have to switch out the lowers this spring. The one on the boat has over 950hrs on it and the upper gears look great. I need to rebuild the upper pin in the gimbal as it has too much play. I really think the only reason I have any walk is play in the gimbal housing though. Running all the way up to 75mph or the boat is rock solid.

On the prop issue. This boat handle and planes better with a 4 blade. More of a neutral to stern lifting prop. The boat really wants to carry the bow naturally and a 3 blade like the Mirage or a Laser wants to pull the whole front end up and not get you on the pad very quickly. Running a 27p Quad IV, this boat planes almost instantly. Tried a 23p Mirage and it took 3 times as long to plane and felt like it dug the boat in. Once on the pad it carried the bow so much it would get a slight wobble and lose handling or feel unsettled.

nice!

where do you boat?

Central Ky. mainly Herrington Lake in Lancaster, Ky. Also try to hit Cumberland and Laurel Lake a few times a yr. I live in Lexington, Ky.

Thanks guys, I was able to get it up on the pad and pretty much elminate the chinewalking. There's still a alittle but alot better. I still can't get any speed out of her. Still only getting around 63 mph with the 23 p mirage. I'm assuming its the prop holding me back

ok ,we were up at summerville WV. this summer and there was a 22 just like yours and it sounded real good but we never got to see it up close . Your pic of the boat running (that looks killer by the way ) looks a lot like that lake is why i ask.

I have a 22 with a 525EFI in it. I have a 5 blade 30" pitch Throttle Up prop. I have seen 96mph on the gps. I The boat wanted to chine walk in the lower to mid 80s. We lowered the outdrive 1" and the chine walk went away as long as it was trimmed out. Now, it will only do about 92mph, but it is a stable ride. I had an 1988 with a 7.4l and a 23" pitch and could only get 63.5mph out of it. If you are making the horsepower, you need more pitch and trim out to carry the bow on the pad. We were playing with trim and moving weight around a couple of days ago. Rough sea trim it in and go slow, about 50 to 60mph. anything over 60 and it really needs to be on the pad. When you are ready to change that outdrive, call the guys at Velocity, They put the Sportmaster outdrive with the ITS system on my boat which is where a lot of that top speed is coming from. The hull design is capable of the speed.

John