04-12 x star engine questions

Just was curious as to what people thought of the different engines in these years boats. I know the 8 liter had problems with them. I was curious if the 350 hp engine that was in the earlier years of this boat had problems. Also how well does that engine get on plane if you have around 4,000 lbs of ballast at elevation 800. I was told that i should look for a boat with one of the newer engines and that i would be happier with it. I was looking at an 05 xstar with the 350 hp engine and just wanted to know if this boat would work well with lots of ballast. Ive been wanting an xstar for a long time now but i dont want to get a boat with an engine that is going to struggle getting out of the hole.

The 8 liter had problems...? That is news to me. Those things are bulletproof.


But the star with the 350 horse is probably fine for what you need.

i herd that rusty went through 3 of them before they sorted the issue out. I also thought i red it on here to stay away from that motor but i could be wrong.

i dont know mastercraft all that well but, 4000 lbs of ballast is alot for a 350 hp engine not to mention how your drivetrain will hold up. id seriously doubt long term durability on that combination???? i personally would be getting a big block if i pulled that much weight.

I've never heard about rustys issues....

All I know is that it is a majorly popular motor for the bigger wakeboats and runabouts and GM's big blocks are known for lasting a long time. The 8.2 saw some upgrades but I have put a lot of hard heavy towing miles on an 8.1 in a Suburban and those things are awesome.

and from the strings I've read seem that the extra fuel consumption is marginal if you run heavy

I would not hesitate to get one in a larger boat.



re SX: As far as 4k in a mastercraft.....A friend has run 3-4k in a 2004 X2 with the 350MCX for years and years....boat has almost 1000 hours on it and the thing runs like a top...but I would agree with you that if that was my normal weight then I'd have the bigger motor.

I have an 06 with the 350, I run around 4k in ballast not sure on the exact number it's stock + PWT + 350/400 in dry weight. Does it get up yes, it's right at max though, more then 3 people in the boat and I have to drain some ballast out. I've found the best prop for the job is a 14.75 x 13, it's pretty crazy to me how much a couple hundred pounds can change how it plans out. I've played around a ton with ballast placement I'd say I have it dialed perfect. Do I wish I had the bigger engine sure, but I'd most likely just add more weight at that point and literately be in the same boat I'm in now in regards to planning time

I ride at 25 mph, some in my crew ride 23-26, wake is clean at any length and speed I think.

I know there where some issues with the 8, not quite sure what they where though. But the 400 you can almost sink and it'll still get up.

The 350 is a ridiculous gas hog with the prop I run, I love the wake and the boat though I wouldn't trade it in for much.

Let me know if you have any other questions.

Oh ya my rig is in MN, according to a map I found my elevation is something like 900', not sure if that is right though.

is the 400 a 6.0l? What year did they start making that motor?

A neighbor of mine has an 05 xstar, 2 years ago with 1200 hours the transmission went out. He had been running around 3-3500lbs, since day one. He had the 350. still a great boat, and came as no shock when it happened...it ws just a matter of time.

The MCX with that amount of weight will need a new prop for sure, but it can be done. We have been running a prop from ACME(2195) that gets the boat out of the hole better than anything else but top speed is 34mph and it is running about 4200rpms at 23mph. The prop is for sale if you want it as we are testing a brand new prop from ACME soon.

The LY6 came out in 06 and before that they had the LQ9. The LY6 needs to be reprop too as it doesn't have as much out of the hole power as the RTP/MCX but once out it was much better power.

Jason you're really getting 34 out of that 12 pitch? Any idea what your rpms are 25-26 mph?

What do you want for the prop? Has it ever been repaired? PM me if thats better.

Just bumping this thread back to the top.

There are so many xstars with the 350mcx motor that i just want to know what others thought of this motor while running heavy weight.

I second the Comments of Jason Smith... I had a 2004 that was about the same set as his 2006.....engine weight etc....Now I have a 2008 xstar with the LY6 and it does seem a couple pounds heavier so if there are more than 3 people I don't max out the fly high ballast. I have tried every OJ prop and the 14.75 x 13 is the best hole shot for both the 350 and LY6 in my opinion. I like everything about the LY6 except that it is really loud like a "fast boat" but maybe I am just getting old haha........ I haven't had the opportunity to try any ACME prop's.......I am interested to see the difference if someone, i.e. Jason Smith, tries it and likes it better then that 14.75 x 13 OJ.

-Rob

I have a 2005 Xstar with the MCX. I run the fly high like most everyone else. With more than 3 people I can only fill the back bags half full. The more people you can get in the front the quicker it will get on plane. I will say this it does not jump on plane like the lighter boats. The boat weighs 4200 lbs dry, 200 lbs of speakers and amps, 400lbs of gas, 200 lbs of gear, a few dudes and throw another 3000 lbs on top of that and you got alot of weight to get out of the water, but once you get it on plane the wake is nice. I run the OJ 14.75x13 as well. I run 23-24 MPH at 4000 RPMs roughtly. Top speed is like 34 MPH.

Rob, I ran both the ACME 1285 and OJ 14.75x13 for comparison sake a few years back. I had the ACME a season before OJ came out with the 14.75x13, I ended up selling the ACME and having two OJ's. I just felt the hole shoot was that much better.

Rob I'm curious how much of a difference you notice in your LY6 compared to the MCX? I just sold my 06 today and will be shopping around and keep telling myself to only look at stars with the LY6, is it worth it? Amazes me how many only have the 350. That was the only thing I didn't like about my star was I felt like it needed a bigger motor.

Jason, I am going to struggle to explain it......but if there were 5 gears you had to shift threw, i feel like 2nd gear is where the LY6 is better, and that means the wake shapes up 1 to 2 seconds faster Counting "one one thousand one, one one thousand two............. with the 14.75 x 13 OJ, I think if there is a killer deal on a loaded up flashy xstar and it has the 350 I would still buy it confidentally. I feel that if the LY6 xstar has a "bad driver" start, like turned weird, or doesn't accelerate perfect, then the LY6 "recovers" or plains out faster then a 350 in the same scenario. If there are 2 identical xstar's and one has the ly6 and one has the 350 I am not sure what the cost difference should be or how much more I would spend.

I rode on my buddies 2005 xstar with the 350 last Sunday and we had it maxed out on ballast and fuel with only 2 people in the boat and I really thought it was about the same, we both have the 14.75 x 13 prop. You might start a new thread with the LY6 versus 350. My last xstar had the 350 and 960hrs and was fine when I sold. I have 230hrs on this new ly6 and no problems either. .......So, looking back at my response I feel that I haven't helped you make a decision at all......haha my bad

-Rob

Like Rusty, we went through three 8.1 big blocks in two different X-stars...... and loved it. :-) Man that boat had a crazy wake, but the problem was that it needed a new motor every other month.

We summed it up to the head gaskets blowing. One of the cylinders would take on water, and that was it. Hydra-lock (sp)?

We started carrying around a spark plug wrench so that we could pull the plug, pump out the water, and start it up to drive home.

The MCX 350 is a badass motor. Bullet proof. But it's more fit for an X-2 / X1. The LY6 is the motor to have in the X-star.

I had the MCX 350 in my X-9 - stock prop it did ok with about 2500lbs. I now have the LY6 in my 08 X-Star and it had to be repropped because I added about 900lbs (all in the back) in batteries and god knows what else in subs/wires/amps. Without filling the rear ballast (don't really need it except to surf) and 4-6 people it was a dog. I went with the TZ-X5 and it made all the difference in the world. I have the same motor in my truck and it doesn't have a lot of low end to begin with but I have been very happy with the LY6 overall. I wouldn't want less power....that is for sure.

Anybody added a trim tab to the back of their xstar? Seems like a fairly inexpensive addition that would help getting on plane. I only bring it up because like the OP said there are a ton of MCX xstars out there. He can probably find a lot better deal and the options/colors he likes with the MCX. If he gets the correct prop and spend 750-1000 on a trim tab he may be just fine.

Thanks Rob, that sorta helps lol. I'm sorta right there with you, I'd hate to pass up on a star just b/c MCX vs LY6. I am leaning LY6 though because I'd love to slam it like the CIE guys, not even sure that's possible with the LY6 vs 8.1.

Did you notice much of a fuel efficiency difference in the two?

I test drove the 2013 star a couple weeks back with the 7.4 Ilmor, if you could somehow get that in the old hull style it would be sooooooo sick! That thing will give you whiplash for days.

Theres a few 2011 XStars with the Ilmor 7.4

Jason, I can honestly say that I cant tell the difference in gas on the mcx versus LY6. On both engines I run an extra 300lbs in lead in the nose and with 3 or 4 people in the back it gets up to speed well. When I ride on the mcx one day then ly6 the next i feel that the loudness of the ly6 makes your mind think it is working hard. I feel like I was closer to 4500 to 4600rpm on mcx. I feel like I am now around 4200 rpm weighted up in the ly6. Again, another ambiguous reply by me, my bad haha I have no knowledge on the 8.1. The 7.4 on the 2013 was very impressive!