Power & drive choices
 

I thought there was a thread about this somewhere on here, but I can't find it so….

If you were ordering a new boat..call it a 30-35 V bottom….

Not a race boat…but not a slug either…say twins I/O's in the 600-700 hp range

What power do you put in it & why?

The Merc XR has limitations and the next drive up is "pricey"…

Do you pay the big $$'s for Merc ?

Do you live with rebuilding the XR's as needed?

Ilmor power and their Indy drive?

Pfaff, Teague, BoostPower and an Imco ?

Any thoughts?

I'll bite since you are asking but I'm only speaking as a "reader" because I have only every run, bravo, alpha, and TRS.

You need to answer 3 questions in order to get the most accurate responses consideration
How will you use it?
What is your budget?
Where do you live?

Since others will surely respond to your question I would ask them about Indmar engines? they have marineized the LSA, a proven high horsepower ls motor.



Imore

the answer to your question is a function of cost, speed, and reliability. as a prospective buyer, you need to pick 2.

speed and reliability: 1350's with 6's or 8's (there is no limit)...but the cost will sky rocket
reliability and cost: 525's with bravo's...but you have no speed
cost and speed: blown 572's with bravo's...bye bye reliability

for the purpose of this thread i would choose cost and reliability. in dream world i would have unlimited money but that isnt reality.

for me i would pick a simple 525 hooked to an imco scx for the following reasons:
-relatively easy maintenance, certainly wont be the fastest boat but will be turn key
-the imco scx's have proven to be a lot better than xr's

mercury is great stuff .. butt my pfaffs i wouldnt call a slug .. or potter , gellner , to name a few .. my konrads prs have done well so far .. but a xr save you a trans .. but then also need a good idling motor for i n out of gear , where a transmission softens the blow a bit ,,

Mercury doesn't make 525's anymore so other options would be 520's or 565's. Personally I would go with 700's and 6's. Another thing with Mercury, they want you to buy a motor and drive package together and pricing is way better than just buying a motor.

OK..thanks for all the input & I'm a bit surprised there isn't more love for Ilmor. Dunno why, really, just surprised. I don't know anything about their stuff but it sure looks cool.

So, some more info:

I'm not opposed to Indmar but I believe their largest displacement motor is a 6.2 which is a cool motor; we have an LSA in our ski boat but you have to buzz it to make hp and isn't that hard on drives? Indmar stuff primarily goes in direct or v-drive applications and those are exponentially tougher than a stern drive.

This isn't really a hypothetical exercise, I'm passively in the market trying to figure out exactly what I want. I'd like to have a boat ordered by this time next year.

I'm fairly certain of the hull choice, but power is stumping me.

I understand the "good, fast, cheap - pick 2" concept and don't really have a budget but I want the most bang for the buck. Merc 6's add what ? Roughly 50K to the price for a pair of drives? 60K ? That's a lot of coin if there are alternatives. That's really my question…are there alternatives? It's not a cat, if I was buying a cat hull I wouldn't have this issue.

I'm not "joe offshore racer wannabe". I'm not going to abuse the drives. I have a heavy 24' boat now with a BoostPower twin blower setup that we've got tuned down to 900 hp and I haven't killed the XR drive behind that yet. We're replacing gears about every 60 hours and I'm good with that, I knew what I was getting into & the look on some of the faces when we go around their "hot boat" is worth the price of admission all day long. However, it's a given that these drives are going to take more abuse than the XR in our 24….Lake Mi does that.

So, a baseline of 2 x 700hp that isn't going to get "race treatment" in a 30-35' sport boat and run on Lake Mi when it's nice. Lets say with the cooler and fuel tanks full it weighs 10,000 lbs.

If I'm understand Merc Racing's website, if you buy their 662 or 700 mill you have to choose between a 6 or a NXT that "combines the best of a 6 and an XR". I didn't think there was a "best of the XR" in a big boat with 700hp.

I understand Merc has a bigger dealer network. But 50K more for a pair of drives ? In a boat that isn't going to be raced?

That's exactly why I was looking for alternatives, if there are any.

The way I see it my options are as follows:

Merc 662 or 700 with a 6 drive
or
Ilmor 700 or 725 with an Indy drive
or
BoostPower 700 with an Imco

I'll add that I have no reservations at all with the BoostPower engine; I have one of Alexi's engines now and am very happy with it and the treatment I've received from the BoostPower guys.

More thoughts?

Blown 540 and SCX/SC setups?

700s / NXT

Arneson, Arneson, Arneson and either a Merc 700 or Ilmor in front of it. Forget that inefficient Merc garbage, get yourself about 10 MPH and years of trouble free boating with the same horsepower.

I will tell you one thing 700's in a 30-35' boat...you are gonna need a shoe horn to get them out or hire a midget mechanic. That's gonna be a horrible setup to work on. Our old small block 292 was horrendous.

With that said for brand new 6's you are talking some serious coin. Like 302 said the only other bang for the buck would be Arnesons in that price point but you aren't gonne be swimming off the back of it...like I said it's all about cost, speed, and reliability.

"I will tell you one thing 700's in a 30-35' boat...you are gonna need a shoe horn to get them out or hire a midget mechanic. That's gonna be a horrible setup to work on. Our old small block 292 was horrendous."

I'm not understanding exactly what you're saying. According to the specs I can find, ALL the big blocks are listed at ~33" wide regardless of the HP rating; 700 hp costs as much in width as 500hp….to my knowledge all trailerable boats with bbc twins (excluding the cats that trailer on their side) are a pain in the azz to work on. That's the ante for that type boat. We're in Mi -our boating season is so short we've got lots more time to work on them than we do run them anyway :)

The alternative is to save about 3" per motor and go to blown small blocks. I don't think I want to do that. The boat has 102' beam which will help a bit.

If I HAVE to go to a NXT or 6 I can.

I'd RATHER have someone tell me the Indy or Imco - for the money saved - is a better way to go.

But that's why I'm asking, because I don't know.

Thanks for bringing up the width issue though, I hadn't considered it but don't really see an alternative.

Why do tho keep saying Indy or Imco?? Do you not like Arnesons??

ASD 7Ms!!!

Hands Down Best Option....

Boost Power (or other custom engine build)
Arneson ASD7M (complete setup when rigging new is similar to a mercury XR but stronger then an NXT)

Ilmor 725
Indy drive

If your buying a new boat and are not worried about resale those are your best options.

If your buying a new boat that is a saught after haul to start with and you want resale....

Mercury 700 #6 (nxt is fine but worth it to go #6)

Unique or rare boats are hard for resale anyways so merc power may or may not be benificial

i dont have anywhere near the pockets to afford any of this stuff. i just read alot because its winter. but if it was me, i would go with aftermarket power and arnesons.

One thing when your considering a bravo type drive on a boat of that size and power, look at the size of a bravo transom assembly next to a nxt/6/8, transoms that were built for power and speed. The scx is a great drive but I'd still be concerned with it breaking right off the boat.
And if you're not going to run it hard go 520's and bravos save 100k towards fuel

Has more to do with depth of engine compartment than width. With a longer boat there is more room in front of and behind the motors. Makes it easy to access things on the side, etc. in a 30-35, you will find very little if not any space to work on the engines. Just an FYI. I will never go back to that situation.

best bang for the buck is the merc 520, its xr drive. price impossible to beat. 2 yr warranty pump gas. we have a pair in our 28 saber.
for 700hp love the 725 ilmor indy drive. impressed with the company, putting a pair in the 34 saber picking up next week.
customer service awesome and now have larger dealer network (mastercraft) .
if you go custom, I always stay local, if it break don't have to send to calif/florida. (Wesco, sterling, tyler, scorpion/ilmor...) that's just in Michigan!!

Can you please fill us in on what hull we are dieing to know

ASD 7 and custom power.

1Moses1 is correct , the length of the boat provided it is the standard 8 foot beam will have no bearing on how tight the fit is side to side . The determining factor is length and room in front of the engines . And all are different
RG.

You could go merc 600/XR package add whipple tunes (700hp) swap xr uppers for SCX and and have a perfectly reliable set up. adds about 15k when you consider the sale of your new xr uppers. Thats probably the cheapest none custom power option. (although the power is now some what custom.) But I would still vote custom power/arneson. or second choice would be Ilmor/Indy. But then you also have to consider the extra 5-10k for props. (Arneson/Indy/#6,etc)

Professor_speed props shouldn't be an issue . When I was running SSM #3's I bought a set of Arneson adaptors which alloes you to run any # 6 style prop on a # 3or 4 drive or an arneson drive .
RG.

Thanks Again guys, I'm getting an education here.

I hadn't considered that the depth had as much if not more impact on engine fit than beam, although now that I think about it, it makes sense.

I like the idea of Arneson, provided they have manners similar to an outdrive as far as maneuvering around the marina. I'm not sure why they wouldn't but know less than nothing about them. My other concern re. Arneson drives is accessibility into the boat. I'm guessing diving off the back would not only be a "no" but a "hell, no". Can you stand on them like an outdrive to get back in the boat? Sorry for my ignorance, I've been around boats all my life but have no experience with a surface drive.

Unless something weird happens, we're leaning heavily toward a 32 Schiada. I have a 24 now & will admit I'm a member of their "cult".
Fit, finish, rigging, etc all has to be seen to be believed.

This is our boat in this video: https://www.youtube.com/watch?v=pk-NCFba6nI
The only thing I'd change would be more fuel capacity; when the blowers start singing it's like flushing a toilet.

If their 43 was trailerable I'd seriously consider that hull. I've been in their factory 43 and it's amazing (and for sale), but it has 114' beam and that's a big, big boat. I'm guessing you're seriously limited to where you can slip a boat that big and we want to be able to travel and do the "tourist thing".

Cheers

[ATTACH=CONFIG]535545[/ATTACH]

Lots of room for any power in a full staggered 35. 600/700sci with NXT SSM6 package is super fun to drive and very reliable in this size hull. Proven and desirable for resale as well.

Newer Arnesons/Indy run the same props as #6 drives but they cost a lot more that bravo props was my point.

Just for clarity. We have a propeller guard for the Arnesons which prevents one from landing upon a propeller if one was to fall into the water above the drives.

Me personally, I would not want to fall onto any drive units nor any propeller as there's many threads of people injuring themselves on bravo ad well as outboard propellers.

Cleaved propellers are cleaver propellers and if/when someone wad to fall upon one it doesn't know what it's bolted onto and the injury is the same.

This is our boat in this video: https://www.youtube.com/watch?v=pk-NCFba6nI
The only thing I'd change would be more fuel capacity; when the blowers start singing it's like flushing a toilet.

WOW seriously every square inch of your boat is BEAUTIFUL! Can't wait to see your new one and run with you this summer!

My last boat had ImcoSCX/SCX with Imco transom assemblies not the weaker merc transoms. 1070 hp and 40 pitch speeedmaster props. No issues these drives will handle 700 hp with ease. They are much less hydrodynamic unless the boat is rigged with a high propeller height. I.E. Surfacing. IMO the Arnesons are a great option but market is much smaller on resale as it is with custom engines. Mercurry equals much easier resale which may or may not make any difference to you.

XPower drives are also an option

Has your boat ever seen water? It is Museum quality clean :D
Beautiful boat!
My vote would be Ilmor/Indy

did someone say Arnesons


http://youtu.be/zu98_yPg6aQ

Thanks all.

One of these days I'll post some pics of the wiring and rigging that isn't obvious to the eye. Literally has to be seen to be believed.

She sees the water. To each their own but I'm not really into trailer queens & we all know the guys whose boats seem to lose a bunch of mph somewhere between the parking lot and water :)

To be fair, I haven't seen that so much with the bigger boat guys but we used to - and still do some - play with the smaller boats - and the bull**** factor with that crowd can only be described as "high" but bench racing is part of the fun with any motorsport so I'm not judging. Whatever floats your boat. I don' wan' be no cloud on anyone's sunny day, mon; juss pass de redstripe and we good.

Again, thanks for all the info.

Bigyellowcat,

That is an awesome video.

It's winter so we've got time - someone school me on the Arneson.

Maneuverability around the marina ? Reverse ? How do they compare to outdrives ?

I can see the advantages; more economical, I'm guessing less parasitic hp loss, less drag, "tougher" than most drives, really cool roost.

What is the downside ?

But why aren't more boats equipped with them?

There aren't any downsides, they dock the same as any surfacing drives like a #6, and don't really stick out any further than bravos on 12" boxes. More boats aren't equipped with them because they don't come with a motor package and most people are very misinformed with bad information that they read online.

I think the 7m drive from Arneson is unbeatable. Rik made the steering better and it work just like a simple any other normal set up. And then like 302 said- there really aren't any downsides. And everything he said I agree with. No motor PACKAGE, I mean look how Merc goes about things and the savings you get with going with full engine PACKAGE INCLUDING DRIVE

Very impressive video! I would like to see more pictures of the inside when you can get them.

I personally like the 32' Active Thunder engine compartment for space. I agree that a stagger is pretty ideal, but for a side by side, the A/T compartment has at least 2' of room forward of the engines in a Bravo/ASD7M/IMCO SC/X etc... standard setup. I'm a pretty big guy, but can get around the engines pretty easily too. Even better, the engine hatch includes the back of the back seat. When you open the hatch, the engines are right there. Makes changing sea water pump impellers, spark plugs, and alternators easy. If you have tubular headers, the work gets even easier.
https://lh3.googleusercontent.com/-P...0/IMG_0860.JPG

I opted to go with 6" taller than standard headers, so that caused the need to raise the hatch. I did it for better header runner length, and better anti-reversion properties with mufflers. It's pretty subtle from the outside though.

I've pulled the engines several times with ease... having 540's with AFR heads certainly makes things tighter though.

I personally don't have the budget to justify a new Merc powertrain package. I honestly don't really care for their packages anyway - as they get better, the price goes up astronomically anyway. There are a few excellent engine builders in Michigan that I would say could EASILY beat Merc pricing and can build a motor that has just as good or better parts. The savings would leave you the choice of drives, and potentially better exhaust options.

No matter what engine you pick, going with an XR drive or IMCO SC (same gears) is probably going to be painful. For the cost, SCX and ASD7M's are both proven to hold up. SCX is usually 3-4 mph slower, but runs standard less expensive props. ASD7M needs SSM props, but gets great results across the board.

By the way, I know a guy in the area (West Michigan) selling a pair of IMCO SCX drives that are just broken in (classifieds). :)

Thanks, I'll post more pics soon.

My back seat is easily removable which provides great access to the engine compartment and eliminates the need for any headstand contortions.

Agreed there are some very competent engine builders here in MI but if I go custom power I'll do a BoostPower setup again. I'm very happy with the one I have,they're not far from Schiada, I can get Alexi on the phone, and if it's a simple tuning issue it can be done remotely by plugging in a laptop. If that doesn't work for the cost of an airline ticket and a night on the town (which admittedly could be expensive) Alexi will fly up.

I think based on all they info I've eliminated the XR drive from the equation. I like the idea of the Arneson drive & will talk to Schiada and get their thoughts. If for some reason I don't go that way I'm thinking it will either have custom power and an SCX or an Ilmor with one of their Indy drives; from what I'm understanding the Indy drive robs less hp than either a merc or SCX and is very tough.

I appreciate the tip on the used SCX drives but we need to get a kid out of college before I order the boat and it will be a year or so to get the boat; we're shooting for summer of 17.

thanks

Teague power with SCX drives would be my choice. The reliability of the SCX has proven to be worth the price with anything over 600hp. I would love a 32ish boat with twin TCM 1025s and SCX drives...a 38 Donzi ZR with the same setup would be money.

You have several good options if you want to stick with warranteed power packages:

In the 600 hp range:
1) Mercury 565/Bravo
2) Mercury 600SSCI/Bravo
3) Ilmor 570 (LS)/Teague or Imco

All use Bravo-style props and drives (F-A-R cheaper). The Ilmor will be the lightest, comes with stronger drive options, and will probably use the least fuel. To me the 600 doesn't make sense over the 565 due to the blower.

In the 700 hp range:
1) Mercury 700SCI/NXT or #6
2) Ilmor 650 or 725/Indy

Here, you're looking at pricey Speedmaster style props, but far more robust drives. I'm a fan of the Ilmor package, as it's newer technology, doesn't use a blower, and delivers great fuel mileage. (Gas won't always be cheap.)

Of course, you can still by bobtail engines from either manufacturer, and couple them with Arnesons if you wish. Good Luck!