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bfinley
09-19-2009, 07:37 PM
I'm looking at some used X-1's and X-2's. They both have the 310 HP motor? Is that enough power, or should I hold out for an 350HP MCX? It seems to be a buyers market at the moment, and I have all winter to make my purchase.

I'd like to hear from some people that have the 310 HP motor.

Thanks,

Brandon

ttu
09-19-2009, 07:58 PM
you are going to hear more than you really want to on this subject!:rolleyes:

i have a 07 x2 with the 310 rtp along with the wake prop. i am running factory ballast along with 2 400lb fly high bags in the back along with 400 lbs of pop-products up front and have yet to have a issue getting on plane.

when i was looking i asked the same question because the dealer only had 2 x2's for sale. one with the mcx and one with the rtp. the mcx boat was sold before i made my decision.

from my understanding both engines are close on the low end torque and the mcx takes the advantage at high end.

now with that being said everyone will tell you the resale of the mcx will be better. it looks so pretty:D

Age Fighter
09-19-2009, 08:29 PM
you are going to hear more than you really want to on this subject!:rolleyes:

i have a 07 x2 with the 310 rtp along with the wake prop. i am running factory ballast along with 2 400lb fly high bags in the back along with 400 lbs of pop-products up front and have yet to have a issue getting on plane.

when i was looking i asked the same question because the dealer only had 2 x2's for sale. one with the mcx and one with the rtp. the mcx boat was sold before i made my decision.

from my understanding both engines are close on the low end torque and the mcx takes the advantage at high end.

now with that being said everyone will tell you the resale of the mcx will be better. it looks so pretty:D

Resale is when the bigger engine always is an advantage -- and not just because it looks pretty -- though the MCX does. The more powerful the engine, the less stress it is under while in use. This has more to do with displacement than anything, but there is a feeling among a lot of pre owned buyers that it is much safer to get a 300 hour boat with the bigger engine as opposed to the same 300 hour boat with a smaller engine package.

If you are happy with the boat, then I would not worry. But likely the entire price difference or more will be made up at resale. Of course, if you don't plan to sell it, that is not an issue.

Age Fighter
09-19-2009, 08:30 PM
Resale is when the bigger engine always is an advantage -- and not just because it looks pretty -- though the MCX does. The more powerful the engine, the less stress it is under while in use. This has more to do with displacement than anything, but there is a feeling among a lot of pre owned buyers that it is much safer to get a 300 hour boat with the bigger engine as opposed to the same 300 hour boat with a smaller engine package.

If you are happy with the boat, then I would not worry. But likely the entire price difference or more will be made up at resale. Of course, if you don't plan to sell it, that is not an issue.

oops - I confused the original poster with the first respondent. My bad.
I would hold out for the MCX for the reasons stated above.

3event
09-19-2009, 08:48 PM
I saved this torque curve posted by MYMC originally. Note how the first graph is titled. While the resale discussion continues, keep in mind the math - you're paying less for the boat with the 310 now and you would expect to sell it for less than a boat with MCX a couple years from now. Would the boat actually depreciate more as a % of total cost because it has the base engine? Good question.

FamilyX2
09-19-2009, 08:52 PM
just to clarify.....

RTP: 5.7 L displacement
MCX:5.7 L displacement

JimN
09-19-2009, 09:14 PM
I saved this torque curve posted by MYMC originally. Note how the first graph is titled. While the resale discussion continues, keep in mind the math - you're paying less for the boat with the 310 now and you would expect to sell it for less than a boat with MCX a couple years from now. Would the boat actually depreciate more as a % of total cost because it has the base engine? Good question.

What did the LY-6 do for HP?

JimN
09-19-2009, 09:16 PM
I'm looking at some used X-1's and X-2's. They both have the 310 HP motor? Is that enough power, or should I hold out for an 350HP MCX? It seems to be a buyers market at the moment, and I have all winter to make my purchase.

I'd like to hear from some people that have the 310 HP motor.

Thanks,

Brandon

Enough, for what? You need to have a specific purpose when asking this kind of question. For a large barefooter, I would say it's not enough. For most people who slalom, it should be fine. If you want to pull the skiers' arms out, maybe not.

Age Fighter
09-19-2009, 09:37 PM
just to clarify.....

RTP: 5.7 L displacement
MCX:5.7 L displacement

That's a good point, and resale value usually has more to do with displacement than HP or super charging, etc.

I would also say the tranny is a factor. Does the 310 come with powerslot tranny? I have heard that the great thing about the powerslot is how it enhances the smaller or less powerful engines. (my boat has a 1:1, not a PowerSlot).

Chicago190
09-19-2009, 10:10 PM
That's a good point, and resale value usually has more to do with displacement than HP or super charging, etc.

What are you basing this on? LT1 powered boats have better resale than TBI 350s, and both are 5.7L...

It is pretty much an established fact the MCX has better resale than the RTP. If it wasn't true we wouldn't be considering this question in the first place. I think your first post was correct.

Age Fighter
09-19-2009, 10:31 PM
What are you basing this on? LT1 powered boats have better resale than TBI 350s, and both are 5.7L...

It is pretty much an established fact the MCX has better resale than the RTP. If it wasn't true we wouldn't be considering this question in the first place. I think your first post was correct.

You and I agree -- I kind of over stated it in the first post and under stated it on the second. A more expensive engine of the same size helps re-sale. An engine of bigger displacement helps even more. The old adage: there is no replacement for displacement.

The displacement is more of a key on higher hours I believe, because it allows for lower RPM stress to achieve the same performance.

This is really evident in sterndrives, where say the 23-24 footers are available in 5.0, 5.7 and 8.1 litre engines. At resale, the investment in the bigger engine really pays off.

All inboards come with torqued engines because they are all built to tow and all need hole shot to get riders out of the water. The difference in engines and in resale is likely not quite as dramatic as in IO's, but I think the principle still exists.

mccobmd
09-20-2009, 12:25 AM
I have the X1 with RTP 310 because it is what they had. I haven't had problems with hole shot. It will pull anyone out of the water faster than they can hold on. I think it uses a little less gas but not sure. I'm very pleased with the engine's performance. If you plan on keeping the boat for a while then get the best deal.

Skywalker
09-20-2009, 08:39 AM
I have an 08 x-15 with the 310 horse and it is plenty of power. "I can't belive I am actualy going to say this!" I really dont see needing any more than that.

Jesus_Freak
09-20-2009, 09:04 AM
...The displacement is more of a key on higher hours I believe, because it allows for lower RPM stress to achieve the same performance...

This makes sense. Buyers also consider tangible, measurable factors such as fuel consumption, octane requirement, weight, space occupied by the engine, sound, costs of maintenance, and costs of replacement parts.

Age Fighter
09-20-2009, 09:54 AM
This makes sense. Buyers also consider tangible, measurable factors such as fuel consumption, octane requirement, weight, space occupied by the engine, sound, costs of maintenance, and costs of replacement parts.

I don't know if boat buyers are often that analytical. I think it's more emotional. I can only speak from my own experience -- buying and selling a number of boats and knowing a number of folks in the marine trades. Seems that bigger is better for resale by a long shot.

And bigger (or supercharged) engines really only use more fuel when they are pushed to limits that the smaller engines cannot access. They don't use a whole lot more fuel simply producing the same results a smaller engine does. They just do it with less stress.

bigmac
09-20-2009, 10:34 AM
Very rare here on Team Talk to hear anyone complaining about too much power.

As to resale, if that's important, I'm guessing most people would have an easier time selling an MCX than an RTP. Horsepower and torque graphs are interesting and all, but if you try to sell your RTP at some point down the road, better keep those graphs handy so that you can use them to convince a potential buyer that it's enough engine.

JohnE
09-20-2009, 10:54 AM
We have this question over and over. It's simple IMO. RTP is enough. MCX is better. MCX makes resale easier as a potential buyer won't have to ponder the same question.

Also there is a rare time when too much power is not necessarily desirable. I was advised that the LY6 is too much engine in a 197 or 214 for the course. That for barfooting you'd want it but not so much in the slalom course. That the boat has "too much advantage."

ttu
09-20-2009, 11:19 AM
here is my orginal thread on this topic. enjoy!:D

http://www.mastercraft.com/teamtalk/showthread.php?t=17737

kev88
09-20-2009, 12:21 PM
RTP is plenty for everything you will want to do. RPMs wind up a little higher at higher speeds.

Age Fighter
09-20-2009, 12:28 PM
We have this question over and over. It's simple IMO. RTP is enough. MCX is better. MCX makes resale easier as a potential buyer won't have to ponder the same question.

Also there is a rare time when too much power is not necessarily desirable. I was advised that the LY6 is too much engine in a 197 or 214 for the course. That for barfooting you'd want it but not so much in the slalom course. That the boat has "too much advantage."

Very well said. Enough versus better is the equation. And the boat I sold that allowed me to buy a MC last summer -- beat out a similar boat with a smaller engine to this prospective buyer. I simply advised the buyer to do some research on that boat and engine package, and he came back to me with an offer the next day. I had my MC three days later.

In fairness, the boat I beat out for the sale was way underpowered, which is not the case with the RTP engine. But I always buy with an eye on potential resale, so I'm a big believer in the upper end engine packages if the money for it is affordable going in.

But do explain how the 214 had "too much" engine for the course? I've never pulled a skier in the course, so I admit to ignorance on that, but how can you have "too much?"

flya750
09-20-2009, 12:53 PM
you are going to hear more than you really want to on this subject!:rolleyes:

i have a 07 x2 with the 310 rtp along with the wake prop. i am running factory ballast along with 2 400lb fly high bags in the back along with 400 lbs of pop-products up front and have yet to have a issue getting on plane.

when i was looking i asked the same question because the dealer only had 2 x2's for sale. one with the mcx and one with the rtp. the mcx boat was sold before i made my decision.

from my understanding both engines are close on the low end torque and the mcx takes the advantage at high end.

now with that being said everyone will tell you the resale of the mcx will be better. it looks so pretty:D

Quick question? How is an X7 coast guard approved with all that extra ballast weight? Am I missing some thing? Is the coast guard looking the other way for wake board vessels???

bigmac
09-20-2009, 01:10 PM
Coast Guard capacity and weight regulations only apply to boats 20 feet long or less. Some mfgrs (including MasterCraft) elect to be have their boats certified by the NMMA, which uses USCG regs as a base, but applies to boats up to 26 feet long. Ballast isn't included in the weight limit placards on NMMA-certified boats, so yes, it's possible or likely that a wakeboard boat with full ballast and several people is exceeding the weight limits on its NMMA capacity plate.

However, enforcement is done state-by-state. Minnesota, for example, by statute can only enforce weight limits on boats 20 feet or less since they are the only ones required to have capacity plates on them. I suppose a boat that was ridiculously overloaded could get a general-purpose citation for "unsafe boating", but I've never heard of that happening around here. Technically, I suppose the X2 and X7 fall into the capacity-plate-required category, so technically they could get dinged by state enforcement agencies.

The only capacity limitations that seem to be applied here are for number of people, but again, the capacity plate isn't taken into account (if 20 feet or less). They DO require that everyone on the boat have a place to sit.

flya750
09-20-2009, 02:18 PM
Coast Guard capacity and weight regulations only apply to boats 20 feet long or less. Some mfgrs (including MasterCraft) elect to be have their boats certified by the NMMA, which uses USCG regs as a base, but applies to boats up to 26 feet long. Ballast isn't included in the weight limit placards on NMMA-certified boats, so yes, it's possible or likely that a wakeboard boat with full ballast and several people is exceeding the weight limits on its NMMA capacity plate.

However, enforcement is done state-by-state. Minnesota, for example, by statute can only enforce weight limits on boats 20 feet or less since they are the only ones required to have capacity plates on them. I suppose a boat that was ridiculously overloaded could get a general-purpose citation for "unsafe boating", but I've never heard of that happening around here. Technically, I suppose the X2 and X7 fall into the capacity-plate-required category, so technically they could get dinged by state enforcement agencies.

The only capacity limitations that seem to be applied here are for number of people, but again, the capacity plate isn't taken into account (if 20 feet or less). They DO require that everyone on the boat have a place to sit.


ahh..Okay.. Thanks for clearing it up for me.:cool:

Chicago190
09-20-2009, 04:41 PM
But do explain how the 214 had "too much" engine for the course? I've never pulled a skier in the course, so I admit to ignorance on that, but how can you have "too much?"

Two reasons. First, some lakes, Okeeheelee in Florida comes to my mind, have a HP restriction. Second, skier preference of how the pull feels. The LY6 will give a harder pull which some skiers may not like. However, I'm not sure if this is still true with the adoption of GPS speed control.

WTRSK1R
09-20-2009, 05:27 PM
I have the 310 HP in my 197 and the only time I wish I had more is when my one of my friends is barefooting. He is nearly at WOT to get the speed he needs. On the other hand, plenty of power for slalom, Barefootin, and most anything else unless you are on the heavier side.

Steve

ttu
09-20-2009, 07:19 PM
Quick question? How is an X7 coast guard approved with all that extra ballast weight? Am I missing some thing? Is the coast guard looking the other way for wake board vessels???

sorry just got back from the lake. i have a 07 X2 not a X7! by the way i love the way direct drives drive.:D

FrankSchwab
09-20-2009, 07:38 PM
I've got the older MX-Plus (5.7 L at 308 HP), and the only time I've wanted more power was when I pulled up 5 skiers simultaneously. I don't pull barefooters, so I can't comment on what's needed there.

Unless your skiers are more manly than mine, NOBODY gets full throttle on pull-up anyway (except the party of five). And if you're not hitting full throttle, the 30 HP differences between boats are not coming into play.

/frank

Thrall
09-21-2009, 11:39 AM
I'd say if you were planning on keeping the boat, the 310hp would be fine, in low altitude areas (like WI). For resale, I'd try to find a deal on the MCX, as it's more popular and has the "350 hp" stigma.
I'm glad I got the MCX and the LY6 or L18 wouldn't be out of the question where I live. The altitude sucks the power out pretty quick, like my MCX X2 with factory ballast and 17 pitch prop will barely pull a 200lb person up to speed on a wakeboard. I need to prop down, I realize, but it's pretty bad at anything over 6000' elevation.
For resale, given that alot of out boats cross the country changing owners (my X2 was from Las Vegas, had people calling from as far away as IL on my Prostar), I'd consider the biggest hp available and knock price off considerably for smaller motors.

JohnE
09-21-2009, 11:45 AM
But do explain how the 214 had "too much" engine for the course? I've never pulled a skier in the course, so I admit to ignorance on that, but how can you have "too much?"


I'm not a good enough skier for it to matter. But I was told that the added power of the LY6 can give a little too strong of a pull.

bigmac
09-21-2009, 11:59 AM
I guess if I were going to spend $30,000 - $50,000 on a boat, I'd want an engine in it that was better than "good enough".

Age Fighter
09-21-2009, 12:01 PM
I'd say if you were planning on keeping the boat, the 310hp would be fine, in low altitude areas (like WI). For resale, I'd try to find a deal on the MCX, as it's more popular and has the "350 hp" stigma.
I'm glad I got the MCX and the LY6 or L18 wouldn't be out of the question where I live. The altitude sucks the power out pretty quick, like my MCX X2 with factory ballast and 17 pitch prop will barely pull a 200lb person up to speed on a wakeboard. I need to prop down, I realize, but it's pretty bad at anything over 6000' elevation.
For resale, given that alot of out boats cross the country changing owners (my X2 was from Las Vegas, had people calling from as far away as IL on my Prostar), I'd consider the biggest hp available and knock price off considerably for smaller motors.

Good points on the elevation issue. I had not thought of that.

So it seems to me like the verdict is in: the 310 is enough to use the boat for what it is intended. At the low end, perhaps no different than the MCX, and low end is where the vast majority of a boat engine performs.

But you will likely "pay for" the 310 if and when you ever attempt to sell it. As happy as current owners of the 310 are -- and as irrelevant is that extra HP is to their enjoyment -- and as illogical as might seem now -- the engine size and HP will indeed matter a lot at resale. That's a law of nature with pre owned boats.

dstone124
09-21-2009, 12:16 PM
so I've got an 06 x7 with the RTP and I use it primarily for slalom. I've noticed it a little doggy outta the hole, especially so when on a short set up private lake. The boat has to hustle to make it to 36 before the 180's. So my question is this, I've spoke with Eric at OJ about a prop change, but what about engine modifications. I read a thread that MYMC had posted regarding his supped up TT, but he was vague on the details for obvious reasons. So what's anybody ever done to crank out a little more pop?!?

Age Fighter
09-21-2009, 12:37 PM
There maybe engine mods, but the quickest, easiest and least expensive is the prop route. If you don't mind losing a touch at top end, Eric can make that "doggy" start a thing of the past. Heck, he may not even cost you any top end.

bturner2
09-21-2009, 02:15 PM
I've had the RTP in both my last boats (03 X2 and 07 X2) and have had no issues what so ever. That may be because I spend the vast majority of my time on the water surfing, wakeboarding and skiing. So that pretty much means the boat rarely goes over 36 MPH. Don't do any bare footing, don't do any wakeboard boat racing so I really don't care about the extra 3 - 5 MPH on top end.

I will say that the MCX is very pretty and I certainly would want one if I found one at a good price but that alone is a fools move for buying a boat. I'm more concerned with the hours, options and condition of the boat (a MC boat that is) than just the engine that's in it. You'd also have to consider how much more you'd be willing to pay for the MCX. I personally would have a difficult time spending more than a grand more for the MCX given two like boats. Based on the strong opinions voiced on this subject I know there are those that wouldn't be own an RTP and would be willing to pay maybe $4K or $5K more but I just can't see it based on my experience with the RTP.

I will also say that when selling my last boat I did miss a sale to a guy that insisted on having an MCX in a 03 X2 and he was only too happy to tell me that. That really didn't bother me though as I had 3 buyers looking at the boat within a week. If you're really worried about resale stay away from the funky or over the top color combinations that are out there.

woftam
09-21-2009, 02:24 PM
I've had the RTP in both my last boats (03 X2 and 07 X2) and have had no issues what so ever. That may be because I spend the vast majority of my time on the water surfing, wakeboarding and skiing. So that pretty much means the boat rarely goes over 36 MPH. Don't do any bare footing, don't do any wakeboard boat racing so I really don't care about the extra 3 - 5 MPH on top end.

I will say that the MCX is very pretty and I certainly would want one if I found one at a good price but that alone is a fools move for buying a boat. I'm more concerned with the hours, options and condition of the boat (a MC boat that is) than just the engine that's in it. You'd also have to consider how much more you'd be willing to pay for the MCX. I personally would have a difficult time spending more than a grand more for the MCX given two like boats. Based on the strong opinions voiced on this subject I know there are those that wouldn't be own an RTP and would be willing to pay maybe $4K or $5K more but I just can't see it based on my experience with the RTP.

I will also say that when selling my last boat I did miss a sale to a guy that insisted on having an MCX in a 03 X2 and he was only too happy to tell me that. That really didn't bother me though as I had 3 buyers looking at the boat within a week. If you're really worried about resale stay away from the funky or over the top color combinations that are out there.

The guy who insisted on a 03 X-2 with MCX and was only too happy to tell you that.... just never knew who his daddy was.....;)

bfinley
09-21-2009, 07:33 PM
I should have clarified. I'm primarily interested in having enough power for wakeboarding and skiing. However, there is the occasional barefoot run. I think I'm probably going to hold out for an MCX. I know I'd be kicking myself if I made a purchase and didn't get exactly what I wanted - you can never have too much power. Plus I have all winter to shop.

Thrall
09-21-2009, 07:35 PM
Good call. There's some deals out there. Took me 3 months to find the right deal (after passing up "the right deal" once just to see if I could do better).

JohnE
09-21-2009, 07:54 PM
so I've got an 06 x7 with the RTP and I use it primarily for slalom. I've noticed it a little doggy outta the hole, especially so when on a short set up private lake. The boat has to hustle to make it to 36 before the 180's. So my question is this, I've spoke with Eric at OJ about a prop change, but what about engine modifications. I read a thread that MYMC had posted regarding his supped up TT, but he was vague on the details for obvious reasons. So what's anybody ever done to crank out a little more pop?!?


He was upgrading either an MCX or the LY6......it's the boat that Yellow78 bought. I believe the mods didn't turn out as well as planned and he kept the engine stock.

Call him if you want some advice. He's always willing to help. Though I think he's out of town this week.

EarlyriserX9
09-21-2009, 10:34 PM
I have the RTP 310 in my 03' X9 and have no complaints. I mostly barefoot then wakeboard, but often pull out the slalom ski. I barefoot on my buddy's PS209 with the MCX motor during the week and we switch to mine on the weekends. We don't have a problem on my boat, even though it is heavier with the tower, speakers, etc... I would prefer the MCX motor, but I got such a great deal that I am proud to run the RTP. I also plan to keep this one for a long time, so resale is not on my radar.

Jesus_Freak
09-22-2009, 07:08 AM
...And if you're not hitting full throttle, the 30 HP differences between boats are not coming into play...

Would someone ever be able to measure the difference? No...I agree with you.

Is it really different? Yes. For a given power requirement, larger displacement engines tend to consume more fuel. But again, I think we decided that there are only 14 of us that are concerned with fuel consumption. :D

Age Fighter
09-22-2009, 08:30 AM
Would someone ever be able to measure the difference? No...I agree with you.

Is it really different? Yes. For a given power requirement, larger displacement engines tend to consume more fuel. But again, I think we decided that there are only 14 of us that are concerned with fuel consumption. :D

JF, far be it for me to question anything technical stated by you (and no, I am not being sarcastic!!) -- but I thought the referred to thread had us decide that larger displacement engines tend NOT to use more fuel for a given power requirement. In fact, I think that thread said that since those engines reach that requirement quicker on the throttle, larger engines might actually use less in a practical sense.

But I agree, maybe -- MAYBE 14 are concerned with fuel consumption.

JohnE
09-22-2009, 08:54 AM
Would someone ever be able to measure the difference? No...I agree with you.

Is it really different? Yes. For a given power requirement, larger displacement engines tend to consume more fuel. But again, I think we decided that there are only 14 of us that are concerned with fuel consumption. :D

And at least 10 of you are lying about it.:D

The rest tend to be the ones with the small ummmmm units.:D


I'm still yet to hear anyone with the MCX, LY6, or L18 post that they wish they'd gone with the RTP.

Age Fighter
09-22-2009, 09:19 AM
And at least 10 of you are lying about it.:D

The rest tend to be the ones with the small ummmmm units.:D


I'm still yet to hear anyone with the MCX, LY6, or L18 post that they wish they'd gone with the RTP.

Moderator said this, not me :D:D

Jesus_Freak
09-22-2009, 01:34 PM
JF, far be it for me to question anything technical stated by you (and no, I am not being sarcastic!!) -- but I thought the referred to thread had us decide that larger displacement engines tend NOT to use more fuel for a given power requirement. In fact, I think that thread said that since those engines reach that requirement quicker on the throttle, larger engines might actually use less in a practical sense.

But I agree, maybe -- MAYBE 14 are concerned with fuel consumption.

Excellent post. :D Thanks.

Maybe MYMC, TRBenj, JimN, others can beat me up, but I thought it was concluded that a larger displacement engine requires less mechanical loading, and presumably less wear, for a given power requirement.

I am speaking purely of fuel consumption during steady operation at a given power requirement. More mass in moving parts, more area on contacting surfaces (rings, bearings), and larger combustion chambers (flame can only spread in space and time so quickly and efficiently, so bigger = worse) will consume more fuel.

Again, I am talking about general trends here; I know nothing about how these particular engines compare with one another in regards to these measures I mentioned.

Jesus_Freak
09-22-2009, 01:39 PM
And at least 10 of you are lying about it.:D

The rest tend to be the ones with the small ummmmm units.:D



OK, so ~ 10 are lying and the rest have small units? I am not lying, so I can only conclude that I fall into the later category. We have met at CSM twice, but you have never seen my unit. I think you may be reaching an unfair conclusion.:D

mccobmd
09-22-2009, 01:45 PM
Excellent post. :D Thanks.

Maybe MYMC, TRBenj, JimN, others can beat me up, but I thought it was concluded that a larger displacement engine requires less mechanical loading, and presumably less wear, for a given power requirement.

I am speaking purely of fuel consumption during steady operation at a given power requirement. More mass in moving parts, more area on contacting surfaces (rings, bearings), and larger combustion chambers (flame can only spread in space and time so quickly and efficiently, so bigger = worse) will consume more fuel.

Again, I am talking about general trends here; I know nothing about how these particular engines compare with one another in regards to these measures I mentioned.
What I get out of what JF is saying is that in general a bigger engine doing the same work will use more gas to do it. That is certainly true in automobiles where some models have the same body but the 4 cyl moves the car on the highway at the same speed as the 6 cyl but uses less gas to do it. And truthfully I got the RTP in my X1 because that is what they had in the color I want. I wouldn't upgrade if I could because it does all I want it to do. I would however if I were considering trading in the next few years shop for a deal on the MCX.

Roonie's
09-22-2009, 01:47 PM
The torque curves for both the MCX and RTP are almost identical (with the MCX being ever so slightly above the RTP) all the way through the range until you hit around 5000 rpm and then the MCX pulls away hard. The only noticeable difference will be in the high RPM range. Same platform engine and the MCX sucks in more air at the higher RPM's due to the really cool plenum it has so it gives it the 30 more HP. It is only felt at the higher RPM's. I asked Indmar this exact question and this is what they told me and sent me the dyno tests to prove it.

mccobmd
09-22-2009, 01:47 PM
And at least 10 of you are lying about it.:D

The rest tend to be the ones with the small ummmmm units.:D


I'm still yet to hear anyone with the MCX, LY6, or L18 post that they wish they'd gone with the RTP.

It's not always the size of the unit but what you can do with what you have;)

Age Fighter
09-22-2009, 02:26 PM
The torque curves for both the MCX and RTP are almost identical (with the MCX being ever so slightly above the RTP) all the way through the range until you hit around 5000 rpm and then the MCX pulls away hard. The only noticeable difference will be in the high RPM range. Same platform engine and the MCX sucks in more air at the higher RPM's due to the really cool plenum it has so it gives it the 30 more HP. It is only felt at the higher RPM's. I asked Indmar this exact question and this is what they told me and sent me the dyno tests to prove it.

That is correct, but there was a link to a thread that was actually comparing big blocks and small blocks. While that is not exactly the 310 enough question, it is related.

And I swear I think that thread concluded that the big blocks did not use more fuel -- when it was simply doing what the small block could not do (the only valid comparison). It only used more fuel when it produced more power.

Power to power, it takes far less RPM's for the bigger engine to equal the output, thus the negation in fuel consumption.

JimN
09-22-2009, 03:54 PM
What I get out of what JF is saying is that in general a bigger engine doing the same work will use more gas to do it. That is certainly true in automobiles where some models have the same body but the 4 cyl moves the car on the highway at the same speed as the 6 cyl but uses less gas to do it. And truthfully I got the RTP in my X1 because that is what they had in the color I want. I wouldn't upgrade if I could because it does all I want it to do. I would however if I were considering trading in the next few years shop for a deal on the MCX.

The 4 cylinder motor has to work harder to cruise at the same speed as a 6 cylinder motor, or the transmission must be geared to allow the smaller motor to operate in its most efficient band. As shown on the British show about cars, where they test and drive them all over, the Prius used more GPM than the BMW M3 when both drove around the race track at 50 MPH. At 60MPH, it was even worse. The smaller one, if not geared favorably at the speed in question, will have to deliver more fuel because the throttle will be open more, The Prius was at about 80% throttle when the M3 was at about 30%, both going the same speed.

The answer is, "It depends". What speed, what load, air temperature/pressure, etc. I would think Indmar has stats on fuel consumption for their motors.

wheeler
09-22-2009, 04:35 PM
what was the upcharge $$$ difference for an MCX over the 310?

Roonie's
09-22-2009, 04:52 PM
The 4 cylinder motor has to work harder to cruise at the same speed as a 6 cylinder motor, or the transmission must be geared to allow the smaller motor to operate in its most efficient band. As shown on the British show about cars, where they test and drive them all over, the Prius used more GPM than the BMW M3 when both drove around the race track at 50 MPH. At 60MPH, it was even worse. The smaller one, if not geared favorably at the speed in question, will have to deliver more fuel because the throttle will be open more, The Prius was at about 80% throttle when the M3 was at about 30%, both going the same speed.

The answer is, "It depends". What speed, what load, air temperature/pressure, etc. I would think Indmar has stats on fuel consumption for their motors.

Same theory applies to voltage. A 220 amp wired motor will use a lot less energy then the same 110 amp motor wired.

Jesus_Freak
09-22-2009, 04:58 PM
The 4 cylinder motor has to work harder to cruise at the same speed as a 6 cylinder motor, or the transmission must be geared to allow the smaller motor to operate in its most efficient band. As shown on the British show about cars, where they test and drive them all over, the Prius used more GPM than the BMW M3 when both drove around the race track at 50 MPH. At 60MPH, it was even worse. The smaller one, if not geared favorably at the speed in question, will have to deliver more fuel because the throttle will be open more, The Prius was at about 80% throttle when the M3 was at about 30%, both going the same speed.

The answer is, "It depends". What speed, what load, air temperature/pressure, etc. I would think Indmar has stats on fuel consumption for their motors.

Great points...the higher/lower answer for relative fuel consumption between two engines operating under a given set of conditions depends on those conditions. Makes sense. I was making far too general of a statement. Thanks.

mccobmd
09-22-2009, 05:13 PM
The 4 cylinder motor has to work harder to cruise at the same speed as a 6 cylinder motor, or the transmission must be geared to allow the smaller motor to operate in its most efficient band. As shown on the British show about cars, where they test and drive them all over, the Prius used more GPM than the BMW M3 when both drove around the race track at 50 MPH. At 60MPH, it was even worse. The smaller one, if not geared favorably at the speed in question, will have to deliver more fuel because the throttle will be open more, The Prius was at about 80% throttle when the M3 was at about 30%, both going the same speed.

The answer is, "It depends". What speed, what load, air temperature/pressure, etc. I would think Indmar has stats on fuel consumption for their motors.

It really comes back to my RTP is paid for and I love it.

kyfooter
09-23-2009, 02:04 PM
I have heard that there is up to a 10% tolerance in horse power ratings...can't recall from whom I heard this, but I do believe it was an ASE certified mechanic. Can anyone else comment as to whether that is indeed accurate?

Regardless, aren't we splitting hairs? 310 vs 350 is a lot of get-up regardless (my old MC had 240 and I never felt under powered). If the above 10% tolerance holds true, there is a good chance the actual hp is hardly different at all (or meaningfully different if the 310 is only putting out 280 or so and the 350 is putting out 385). With both being 5.7L engines, aren't all the comments about the smaller motors working harder to do what the larger motors do moot points?

I'm not current on the engines, but I believe one difference earlier on was the 310 was a throttle body fuel injected motor, and the 350 was multi-port. I would assume that may make the 350 slightly more fuel efficient...but is fuel efficiency that important? "Fuel efficient" and "boat" don't really belong in the same sentence unless the words "are not" come after boat and before fuel efficient.

MCX does look cool though...someone mentioned there being a difference between the engines at 5,000 RPM...what? I didn't know any of the engines actually reached 5,000 RPMs outside of a test room.

Resale: Bigger is typically better. But my 310 pulls me barefooting with plenty of power, and has a quicker hole shot than my friend's Malibu with a 385 hp engine. The only thing my engine won't do is turn 5,000 RPMs...but I've yet to be in a MC or Nautique that did hit 50 mph.

CruisinGA
09-23-2009, 04:29 PM
I'm not current on the engines, but I believe one difference earlier on was the 310 was a throttle body fuel injected motor, and the 350 was multi-port. I would assume that may make the 350 slightly more fuel efficient...but is fuel efficiency that important? "Fuel efficient" and "boat" don't really belong in the same sentence unless the words "are not" come after boat and before fuel efficient.

For a given displacement, more efficient=more powa. Hence three different ratings for 3 engines with the same displacement.

FWIW, 330 hp is also multi-port injected.

flipper
09-23-2009, 04:43 PM
To answer your question, yes it's enough. It comes down to is the extra little bit of power worth the extra $$$ to you?

JimN
09-23-2009, 08:39 PM
I have heard that there is up to a 10% tolerance in horse power ratings...can't recall from whom I heard this, but I do believe it was an ASE certified mechanic. Can anyone else comment as to whether that is indeed accurate?

Regardless, aren't we splitting hairs? 310 vs 350 is a lot of get-up regardless (my old MC had 240 and I never felt under powered). If the above 10% tolerance holds true, there is a good chance the actual hp is hardly different at all (or meaningfully different if the 310 is only putting out 280 or so and the 350 is putting out 385). With both being 5.7L engines, aren't all the comments about the smaller motors working harder to do what the larger motors do moot points?

I'm not current on the engines, but I believe one difference earlier on was the 310 was a throttle body fuel injected motor, and the 350 was multi-port. I would assume that may make the 350 slightly more fuel efficient...but is fuel efficiency that important? "Fuel efficient" and "boat" don't really belong in the same sentence unless the words "are not" come after boat and before fuel efficient.

MCX does look cool though...someone mentioned there being a difference between the engines at 5,000 RPM...what? I didn't know any of the engines actually reached 5,000 RPMs outside of a test room.

Resale: Bigger is typically better. But my 310 pulls me barefooting with plenty of power, and has a quicker hole shot than my friend's Malibu with a 385 hp engine. The only thing my engine won't do is turn 5,000 RPMs...but I've yet to be in a MC or Nautique that did hit 50 mph.

A couple of the things that have changed over the years is the weight of these boats and the amount of wetted surface, both of which make higher HP and torque necessary and desirable. Add 1200 lb of ballast and you really need more.

JimN
09-23-2009, 08:43 PM
Same theory applies to voltage. A 220 amp wired motor will use a lot less energy then the same 110 amp motor wired.

That would be 220 and 110 volts, not Amps and the power formula comes out equal for both. Of you have a 1 HP motor and 1 HP=746 Watts, if it can be wired for both voltages, the measured current will be twice as much at 110V. P=I x E, so at 110V, it draws 6.782A and 3.39A at 220V.