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kgturnbull21
06-03-2015, 04:25 PM
I have a 2007 Mobius LSV with a cracked engine block. The serial# for the block is 14093638 and the serial# for the heads is 10239906. I was thinking about going down the path of purchasing a long block and reusing all the other components. I'm wondering if there is a long block setup I could purchase that would give me a little more hp without having to make any other modifications. Any suggestions? If I do put in something that has more power will all of my other components be able to handle the added power?

mmandley
06-03-2015, 08:17 PM
Adding power would depend on how much power you are planning to add.

The Indmar 325 was also the 340 and very similar the 345 Surf addition.
Honestly I would contact Indmar and talk to them about your ideas.

When adding power the main things you change are, intake, heads, cam, and injectors. If you change to much of any one of these the ECM won't be programmed for the changes and you can actually lose power. If you are dealing with a dealer, or installer who has the ability to program your ECM for the changes then you are good to go.

As for the other engine components they don't care about power, they only care about mounting.

Your Trans on the boat would be my only other concern with adding power, I am not savy in boat transmissions so I don't know how they really accept and deal with power.

Fastest1
06-03-2015, 08:36 PM
What are you looking to obtain?
More torque or speed?
And why?
Any engine builder would want to know the same things. Not trying to offend. You need specific goals in engine building.

Have you tried other props?

kgturnbull21
06-04-2015, 12:02 PM
Thanks for the responses and no offense taken. I believe I have an Indmar 325 Assault in my boat, I was basically wanting to get the hp and torque of the 340. I mostly wakeboard behind my boat and I feel as if it has plenty of power to meet all of my amateur wakeboarding needs. Since I had to replace the block anyways I figured why not see if I can get a little more power while I'm at it. I am curious about the transmission as mentioned by mmandley.

Fastest1
06-05-2015, 09:40 AM
Being that the prop would most likely cavitate before any damage is likely. Makes me think the transmission will be ok. Unless you stick a blower on the new motor. You arent planning a blower are you?

ranger098
06-05-2015, 12:37 PM
i rebuilt an engine in a Mastercraft X2 that i now sold, and believe me when i say this that it is way better to stick with what you had rather than try to improve. Youll open up a can of worms on top of your can of worms. get her rebuilt and get back out on the water!

To get more power could go to MPI and/or a newer intake manifold if yours isnt the best already. The blocks are almost always the same, chevy 350. But if you go to MPI (multi port injection) you need a new ECU (roughly 1000 bucks), or maybe you can send yours to indmar and they can reflash it. Then you need to make sure your ecu works with your dash guages, sensors, etc. And then what happens when something doesnt work right? Turns into a nightmare quick

Also not trying to have a negative attitude, just trying to help you see what you might be getting into! My suggestion is get a new short block and everything should switch over from there. michigan motors i believe is a great source for you.

N2OGTO
06-12-2015, 04:21 AM
I would Ls swap it using a 5.3 truck motor. I've already decided that's what I will be doing if something should ever happen to mine. The exhaust manifolds are readily available online and 5.3's are a dime a dozen. With the right camshaft you can see around 400 hp. But if you don't have tuning capabilities of the engine or the means to make an engine harness, I'd say forget it and go with what came from the factory.