shortened drives
 

anyone tried short drives on a baja 342 ?thinking of imco or the like or is this a mad idea kind of wondering if anyone else ever tried it?

Dock Holiday said he tried some 1" shorties on his 36 & was unimpressed. I have 3" shorties on boxes on my 29 & I like them, although I don't know if they are any faster than stock lengthers.
If you decide you want some. I know a guy woho sells them. My advice would be to get 2" shorties & if they are too short, space them down 1/2 inch at a time. There is only about $250 difference between a 1" & 2"

has anyone tried putting a shortie on a 25 ol? i wonder if that would do anything. sorry no intention of hijacking.

The guy from Germany has one I think???

They did not work for me at all.

02 model Baja 36 Outlaw. Bravo XR uppers and one inch IMCO shorties.

VERY hard to get on plane. I tried my standard Bravo 1 30 pitch four blades that worked great with standard lowers, I tried 28 pitch Bravo 1'a, and 28 pitch Hydromotive P5X five blades. They all blow out about 2000 RPM and the only way to get on plane is to keep adding throttle and it was around 3800 to 4000 RPM before it climbed out of the hole.

Overall I never saw the top end out of the boat that I did with the standard units. However it did run faster with extra people on board then before. That is a clear indication that the drives changed the center of gravity. Plus we had a good size rooster tail with all the props we tried and that means you are not efficient.

I did add one inch spacers to bring the prop shaft height (X dimension) back to stock, but it did not improve much. The problem with the shorties is you loose the cavitation plate on the lower unit. With that gone you just do not have the leverage you need to get the bow up on a big true deep vee hull boat.

I do not recommend them on Baja's unless you plan to add extensions boxes. Then when you do the math you can put the $$$'s into horsepower and gain more.

Just my personal experience.

Good Luck

Dock, how far below the hull is the centerline of the propeller?
I have mine at 4" right now, but it blows out like a big dog. Always has. I rode with Customtouch Dave & his 29 blew out with stock length bravos on 3 blades.
Mine is a whole different animal, so we won't even get into that.

Yes, WildCard did an extension box and a shorty on his 25. Hard to tell exactly what he gained because he also went from a 496ho to a 525efi?
But he did gain. 11-14 total, guesstimated 3-5 from the xtension box and shorty...

i just have an ho and was wondering what a shortie would do. what do you think a shortie and maybe some spacers would do. if i had to go with a box i would spend the money on mods for the motor.

The spacers are used to bring the drive height back down. You can get them in 1/2 increments from 1/2 to 4" if I rember correctly.
The advice I give to everyone is to start with the shortest drive you can get your hands on, which is a 2" (although you can get a 3") & try it, then start spacing down. It gets expensive. Spacers are about $250 for a 1/2 & up from there!
The difference in cost between a 2" & 1" drive is about $200.
The bad thing is that unless you are willing to live with the quirks of a short drive on a Baja, which will be blowing out comming on plane, don't do it.
It bothers some people to have their boat blow out comming on plane.
I would be more likely in your shoes to mod the motor before I started on drives. It is tricky & expensive to jack with the x-dimension.
So, in closing, spend the $$ on exhaust first. If you are not happy with the gain there, then start on the x-dimension.

thanks.

Yeah, CMI has that set of headers for the 496ho that are good for almost 60hp right out of the box. Probably sound better too.

HOW MANY INCHES IS YOUR DRIVE FROM THE KEEL CENTERLINE MINE WAS 7'' AND WITH THE 2'' SHORTIE IS 5 WHICH MAKES MINE RUN NICE HITTING 83GPS ,I need abigger prop should hit 85 to 86 when its done wild card has a 3'' built into the box from imco stock drive. from what I read. art

Doc, I spend the day with a race rigger today and I am going to go with 2" shorter IMCOs. I am a little worried after your experience, but it also leaves me with a few questions...

1. What do you mean you don't have cavitation plates? The IMCO's use a stainless steel cavitation plate that bolts on to the back like the Merc sportmasters. If you did not have this, it could be part of your problem.

2. What did you do with the props? I was told it is very important to add some "cup" to the props when running shorties. They basically angle the last 1/4" of the prop blades up by 30 deg.

Not to jump in before Doc, but I run 3" shorties on my 29 Outlaw, but I have 12" extension boxes also. I had 1" on before the boxes.
The best way to describe what will probably happen is you will experience a ton of slip comming on plane from appx. 2000 rpm to 4000 rpm, but it will not be enough to keep you from getting on plane. Mine did it with the 1's & with the 3's.
Once the boat comes over on plane it will bring the rpms right back down.
I wouldn't worry about it at all. Run the propellers as they are 1st, then tweak them if you think it needs it, but I doubt it will.
Doc, your turn.

It becomes a center of gravity issue. The two 36 Outlaws that I know of running 1 inch shorties do not have A/C. I do and that the only main difference. One has big power with Whipples and I really do not believe that he has gained anything more with the shorties then he would have seen just with the Whipples. The other boat is still trying props and is living with the difficulties getting on plane.

To answer question #1, YES I had the stainless cavitation plate that bolts on. But you loose the larger one off the lower unit that is much more effective on the Baja.

As for props I tried the 30 pitch Bravo's that I had been running before the change, I tried some 28 pitch Bravo's and also some 28 Pitch Hydromotive P5X 5 blades.

They all planed very slow, the five blades did well at cruise but I lost top end speed with all the props from between 2 to 5 MPH.

I then added 1 inch spacers and it helped slightly, but not worth it overall in my opinion.

Baja told me that I would not like them. They said I would have to power through getting on plane and they were 100% correct. This is no fun, and it is very hard on your outdrives.

With extension boxes they probably would plane better and be closer to stock performance, but it is not worth the expense in my opinion for the maybe 2 MPH gain you may see.

I would be VERY surprised if you could even get on plane with two inch shorties. I'm sure my boat would not after trying the 1 inch.

My guess is that if you put enough cup in the props to get on plane easy that it would greatly effect top end.

We ran a poker run last weekend with the original drives back on the boat and it was NICE. I tried them and wish I had not wasted my time nor money.

I have a set of IMCO inch inch shorties satin finish with 1.5 ratio for sale. New they were $6800.00 for the pair and I'll sell them for $5400.00 / pair and pay the freight charges if anyone wants them. They only have 8 hours on them.

Yes and No.

I agree with your above statements Jason, however you are trying this on a 29 versus a 34 or a 36. If we all have the same engines and drives, then you will get more leverage to get the bow up.

I have A/C and I bet the 342 does also. That with the extra length and there is a big difference.

I was told by a guy in the know that if you have extra people on board riding in the back seat and your boat runs faster with them then without that your center of gravity is off. He has actually added weight in the engine compartment and picked up speed. My 36 was not like this until I added the shorties, and then my boat ran better with more people. You have to get the drive down and the bow up. It is MUCH harder to do with shorties alone.

Personally I would bet that with just two inch shorties and no extension boxes on a 342 that it would not get on plane.

I have to disagree that the slip is hard on drives. My thought is, and I could be wrong, that the drive never comes "unloaded" so there is no shock to the gears. If there is no shock to the gears then there shouldn't be a problem.
Another way to look at it is like a burn out in a car. Lots of slip, but no big bang like airing out.
Mabey I'm wrong?
I do agree with the fact that my setup is wierd & I also think that I would have the same speed up top without the extension boxes or 3" shorties. My thought is that the extension boxes make the 3" shorties work. If I had not gotten the deal on the 3" drives I would not have went with them.
Oh, that & they look soooooo cool! Who cares if it is fast!?

The factory setup works exactly how it should. Deep X means easy to come on plane, easy to turn but it takes lots of trim to get the boat up to speed. In terms of stressing the drives, I look at how much trim the stock config takes on the 36 and I am amazed we have not seen more blown universals. Doc, you are running all on fresh correct? I wonder how much of a difference salt would make due to the bouyancy. I do have A/C in the boat, but can't imagine it making that big of a difference. When I was looking for this boat, I almost bought a Formula and when you talk about having to work it to get on plane... it was extremely hard to get up. Maybe we are just spoiled. I guess time will tell. I will keep you all posted in about two weeks.

Good luck and keep us posted.

I have TWO IMCO one inch shortie lowers for sale.

These have exactly 8 hours on them, they are low water pick up, satin finish, 1.5 to 1 ratio, XR series BIG SHAFT.

I bought them brand new in December 2006 for $3400.00 each and installed them on a 36 Outlaw which was ran the first time in March 2007. My boat does not like them, it is too hard getting on plane.

They were filled new with Royal Purple gear oil and the oil was changed at 5 hours per the suggestion of my drive builder.

These are in perfect condition. My lose is your gain.

$5400.00 per the set, or I will split at $2800.00 each for single.

All shipping paid in lower 48 states via UPS Ground and insured.

I accept VISA, Mastercard & American Express.

Note that IMCO has no warranty on their drives. I bought them without warranty and cannot offer any warranty. These units performed perfectly and are not damaged in any way. All sales are final.

These come with the stainless steel cavation plate as provided by IMCO.

Send me a PM if interested.

I am the guy Dock spoke of with the Whipples. I was/am very dissapointed with the 1" lowers. I have had to keep mine, since I cannot afford to replace them as of yet. My results were not as bad as Dock's because I have so much power. The extra power makes up for some of the difficulty getting on plane. I run Maximus 5 blade props and I can still bust em loose anytime while getting on plane. I also have seen no measurable speed increases yet.

I have not been out yet this year, but this weekend is looking good to do so. I sent my maximus props to Brett at BBlades and they are now custom fit to my boat and its specs. I hope to see at least 2-3 mph gain on top and my planing time should be reduced.

All in all it was alot of money spent with no gains so far. At this point I can only surmise that shorter drives on Bajas only work well if used in conjunction with extension boxes. I am not interested in the time/expense of putting boxes on my boat, so I will live with it as is. It is still alot of fun, but unfortunately the gas prices as of late are going to limit my fun this year.

Hope this info helps others and Dock I am very sorry they did not work for you either.

Smitty

Smitty,

Please don't be sorry. You told me "NOT TO DO IT" and I did not listen.

Maybe we can save someone else time and money.

The other guy that told me he liked his has now said "Welcome To The World of Prop Testing".

It's not for me, just way too much trouble for 2 MPH gain if you were lucky and found the right combination.

Happy boating buddy.

Dock

Doc, did your boat not like the shorties even with the 1" spacers?

Jason,

There was a difference but it was very slight, and not good enough for me to live with. It did not blow out as easy, but I was still close to 4000 RPM before the boat climbed out of the hole.

The lose of the lower cavation plate really hurts in my opinion.

I'm going to run stock and "Be Happy".

Dock

Doc/Smitty,

Did either of you try inward rotation ?

Mine blow out much worse with outward rotation.

I can blow mine loose any time when coming on plane,
by juicing it too hard, then, it's come back off plane,
and try it again:mad:

What I've figured out is to throttle them up to 3200 rpm,
and don't exceed it, let it do it's thing til it rolls over.

It doesn't matter if it's loaded heavily or light, still comes out
of the hole without breaking loose.

JT, does your boat slip really hard comming on plane?
Mine does, but I've never had it blow out to where I've had to stop & start over.
What size wheels are you spinning & what gear ratio?

If I do like I said above, limit it to no more than
3200 rpms, ( if it gets much past that, they unhook)
it doesn't really seem to slip or break loose at all.

It's a tad slower than I'd like it to be ( getting on plane)
but, if I do it this way, it never fails to get on plane.

Maybe I shouldn't have said stop and start over,
but you have to slow down enough to get the props
to hook back up, then try it again.

Props are 32 Max's that Brett worked over, drives
are 1.5's.

Mine does the same thing, but I just power thru it. Mine slipps hard about 2000 & will not climb over if I let it stay there. I have to open it up a little more to get ti to break over.
I might take a video so you can hear & see what it is doing.
It is not a problem to me.
I talked to Jeff B. (Hell Ya @ MWBP) & he said the Cig does the same thing. I've heard alot of other boats do the same thing also. Like I said it really doesn't concern me & I actually think it sounds pretty cool.

JT
I have not tried inward rotation yet. I am kinda afraid of how it affects docking ability. Where I run my boat some of the docking is in very tight confines. Maybe one day when I go out in Lake Michigan I will try it.

Smitty

I did not try spinning them in with the shorties. There is no doubt that it would have been better based on all I have read and been told, but it was so much worse overall then with the stock drives that I did not feel it was worth the effort.

We did spin them in last year with the stock drives and there was no gain at on in performance but it was like driving a single engine boat around the docks. The port drive had to have a lot of throttle to respond.

I have my boat the way I like it, we enjoy it and I plan to leave well enough alone. If I feel the need for more speed down the road I will buy a boat that was designed for it and runs the speed I need from the factory.

Happy boating all and be safe and enjoy your weekend.

Dock you aren't pondering a 35OL with 700's are you? :D

Dave,

I'm really not pondering anything right now in the way of a new boat. But I can tell you that a 35 with 700's would be on my short list if I was looking. That is one sweet setup for sure.

I love the Baja styling and the brand has been good to me, but we also like Cigarette and Fountain as well.

If I where buying I would search the market for the best deals new or used on the following.

35 Outlaw w/ 700's
38 Cig Top Gun 525's to 700's
42 Tiger 575's to 700's
38 Fountain 525's to 700's & #6's
42 Fountain 525's to 700's & #6's.

The fountains would have to be recent models with the new updated interiors.

If it were the wife's decision the list would only have one boat on it, and that would be the 38 Top Gun. She has loved that boat from day one and if I got one it would have to be named "Tommie Gun".

Have a good holiday buddy and be safe.

Tell your brother Blake I said hello!:D

Dock

Almost forgot, but I have a pair of one inch spacers forsale also.

The top 3 are on my wish list too:D

Ed,

Any updates yet?

How did it work out for you?

Dock