Indmar assault mpi 325 or 340

[michaelwinger]

Is there any way to tell which of these engines are in my boat?
Its a 2007 Moomba Mobius LSV.
thanks

[KG's Supra24]

http://bwd.live.mediaspanonline.com/assets/7000656/da266d9c.jpg

http://bwd.live.mediaspanonline.com/assets/6998734/MoombaXLV_20080101_2.jpg

[brain_rinse]

Yep, you can post a pic and we can tell you. But it should say right on the engine cover on the 325. If the cover is missing then you can easily tell based on the risers. If they are a boxy up and out design it's the 325 and if they have cats and have a tubular look it's the 340. How's that for scientific? :)

Nevermind, see KG's post above.

[trayson]

Wait a minute. Are you saying that my boat has the 340?

https://lh4.googleusercontent.com/-_3GyPr6CoB4/VSXl_Ut9SAI/AAAAAAAAYlo/iiprvEscQko/s800/20150408_193627.jpg

[Boonejeepin]

Wait a minute. Are you saying that my boat has the 340?

https://lh4.googleusercontent.com/-_3GyPr6CoB4/VSXl_Ut9SAI/AAAAAAAAYlo/iiprvEscQko/s800/20150408_193627.jpg

That looks just like my 340 cat engine.

[trayson]

That looks just like my 340 cat engine.

YES!!!!!!!!!! *happy dance*

I had assumed I had the 325 all this time. No wonder my boat does good with weight!

[CookieMonster]

Yep, you can post a pic and we can tell you. But it should say right on the engine cover on the 325. If the cover is missing then you can easily tell based on the risers. If they are a boxy up and out design it's the 325 and if they have cats and have a tubular look it's the 340. How's that for scientific? :)

Nevermind, see KG's post above.
http://i872.photobucket.com/albums/ab289/nrla07si/motor.jpg (http://s872.photobucket.com/user/nrla07si/media/motor.jpg.html)

This is the only pic I have of my motor. Any idea?

[brain_rinse]

No cats, so I would guess 325.

[sandm]

your guess is correct.

[CookieMonster]

Sweet! Thanks! What's the difference that gives them more hp? Aren't they all 5.7 GM motors?

[gregski]

Mainly the heads, I would think. The chevy 350 produced anything from about 150-350 hp throughout the years, so there is much more to it than just displacement.

[CookieMonster]

Ok. What does MPI stand for?

[brain_rinse]

multi port injection

[mmandley]

Differences they add to make more or less power generally are, heads, intake, exhaust, tunning.

325 vs the 340 deffiently has different intake, but other then that I think the only real difference is Cats.

Interesting find on the ole interweb.

Indmar's entry-level 5.7L V8 model is called the 320 LCR by Malibu, the RTP1 by MasterCraft and Assault 325 by Skier's Choice. Although this is a 3-star Ultra Low Emissions engine, because Indmar is considered to be a low-volume manufacturer (as is PCM), it has been granted a one-year extension to the EPA mandate, but still can't sell this engine in California this year. - See more at: http://www.boatingworld.com/Engines/Article/Power-for-Pop#sthash.8JPCynrI.dpuf

Mide-range Indmar's version of GM's 5700 VORTEC V-8 is known by many names: the Monsoon 350 by Malibu, MCX by MasterCraft, and Assault 340 by Moomba and Supra. Although Indmar doesn't reveal horsepower ratings, Malibu and MasterCraft call it a 350 hp engine while Moomba/Supra is slightly more conservative and says it's a 340 hp model. All use Indmar's ETX/CAT catalytic converter, which was the marine industry's first ever and solved many of the major problems like dealing with excess heat - See more at: http://www.boatingworld.com/Engines/Article/Power-for-Pop#sthash.8JPCynrI.dpuf

As we know until the last couple years Indmar won't advertise HP TQ rating on its engines. So the 325 has been assumed its a HP rating, as the 340 was assumed a HP rating but the more I read on these 2 engines it sounds like the 325 is really closer to 300hp and the 340 is closer to 325 hp.

Heres another page on the 340.
http://www.boattest.com/engine-review/Indmar-Marine-Engine/321_Monsoon-340
Specs
Horsepower 325-hp
Warranty 3 Years
Displacement (cu/cc) 350.00 cu / 5,735.47 cc
Number of Cylinders 8 Cylinders
Configuration V8
Fuel Delivery Fuel Injected
Full Throttle RPM 5200

[CookieMonster]

Good info. Thanks