600HP LS Marine Engine
Platinum Member
05-04-2011, 11:14 AM
#23
specs
Thanks Bob for the conversion sheet ,
The engine was a new ls 2 block whit l92 heads and high inlet manifold wich the used in the gm trucks .
We stroked it to 403 cid whit a forged rottation assembly from compstar ,compression is 10.5 the valve train is updated whit psi springs the heads are standard we used a ls3 intake manfold and a 90 mm throttle body we used the dry sump sytem of a ls7 on the engine and put cmi headers as exhaust .
the closed cooling we used the components of the pcm z06 marine engine and made them fit .
The engine was a new ls 2 block whit l92 heads and high inlet manifold wich the used in the gm trucks .
We stroked it to 403 cid whit a forged rottation assembly from compstar ,compression is 10.5 the valve train is updated whit psi springs the heads are standard we used a ls3 intake manfold and a 90 mm throttle body we used the dry sump sytem of a ls7 on the engine and put cmi headers as exhaust .
the closed cooling we used the components of the pcm z06 marine engine and made them fit .
05-12-2011, 11:09 PM
#24
Registered
Rays LSM550 and this Mast engine intrigue me and Im mildly shopping this market at the moment.
Thing is I/ had my 500 hp 500/lb ft 406 small block built for about 10 grand. I got about a decade out of it before a rebuild.
It's relatively simple and when something goes wrong I can deal with it.
It idles like a kitten and rocks hard. Very little bling here, she aint pretty but she's got a lot of heart.
I have no doubt both of these wicked small blocks are stouter and cleaner running than mine but 10 to 20K better?
If I'm idling out someplace and one stops running- I'm not sure I can do anything about it.
Seems if Im going to spend that cash a solid BBC is within grasp.
Then again I like having a wicked small block and still laugh out loud while putting big blocks on the trailer.
Uncle Dave
Thing is I/ had my 500 hp 500/lb ft 406 small block built for about 10 grand. I got about a decade out of it before a rebuild.
It's relatively simple and when something goes wrong I can deal with it.
It idles like a kitten and rocks hard. Very little bling here, she aint pretty but she's got a lot of heart.
I have no doubt both of these wicked small blocks are stouter and cleaner running than mine but 10 to 20K better?
If I'm idling out someplace and one stops running- I'm not sure I can do anything about it.
Seems if Im going to spend that cash a solid BBC is within grasp.
Then again I like having a wicked small block and still laugh out loud while putting big blocks on the trailer.
Uncle Dave
05-13-2011, 09:25 AM
#25
Registered
Thread Starter
UD,
Couple things. It would be interesting to look closely at the potential weight savings when comparing LS to your current small block.
Can the LS platform of equivalent HP levels run on lower octane fuel? The Mast engine example above runs on 89 octane. I guess the potential for higher HP LS platforms running 91-93 octane is there.
IMO another advantage besides lighter weight and improved breathing/efficiency is the variable cam timing which gives you more area under the torque curve. This is not considered when just comparing peak HP and torque numbers. The dyno run posted by bor shows 500+ lb*ft of torque from 3400 to 5600 rpm. This is what you will feel in the seat of the pants.
Couple things. It would be interesting to look closely at the potential weight savings when comparing LS to your current small block.
Can the LS platform of equivalent HP levels run on lower octane fuel? The Mast engine example above runs on 89 octane. I guess the potential for higher HP LS platforms running 91-93 octane is there.
IMO another advantage besides lighter weight and improved breathing/efficiency is the variable cam timing which gives you more area under the torque curve. This is not considered when just comparing peak HP and torque numbers. The dyno run posted by bor shows 500+ lb*ft of torque from 3400 to 5600 rpm. This is what you will feel in the seat of the pants.
05-13-2011, 11:37 AM
#26
Registered
UD,
Couple things. It would be interesting to look closely at the potential weight savings when comparing LS to your current small block.
Can the LS platform of equivalent HP levels run on lower octane fuel? The Mast engine example above runs on 89 octane. I guess the potential for higher HP LS platforms running 91-93 octane is there.
IMO another advantage besides lighter weight and improved breathing/efficiency is the variable cam timing which gives you more area under the torque curve. This is not considered when just comparing peak HP and torque numbers. The dyno run posted by bor shows 500+ lb*ft of torque from 3400 to 5600 rpm. This is what you will feel in the seat of the pants.
Couple things. It would be interesting to look closely at the potential weight savings when comparing LS to your current small block.
Can the LS platform of equivalent HP levels run on lower octane fuel? The Mast engine example above runs on 89 octane. I guess the potential for higher HP LS platforms running 91-93 octane is there.
IMO another advantage besides lighter weight and improved breathing/efficiency is the variable cam timing which gives you more area under the torque curve. This is not considered when just comparing peak HP and torque numbers. The dyno run posted by bor shows 500+ lb*ft of torque from 3400 to 5600 rpm. This is what you will feel in the seat of the pants.
The cam phasing is really the big thing it seems to me.
Closed cooling is nice, but Im not running salt so Im not sure what that really buys me.
Yes the torque curve is impressive on those mills, but it doesn't seem 20K better than my garage special.
Seems to me I can about duplicate their performance with a larger cubic inch short block, but I dont know for sure.
Seems like Im better off just building a big block vs the LS/ or Ford, ---thoughts?
UD
Last edited by Uncle Dave; 05-13-2011 at 11:51 AM.
05-13-2011, 12:40 PM
#27
Registered
Thread Starter
Just for grins I pulled up two crate engine packages (I know, auto engines) of similar HP for comparison. I know they are not identical in terms of accessories, but the LS package is $3800 cheaper and make more HP (although I don't think it comes with the ECU). Anyways, I don't think the cost is that much different when comparing apples to apples. Food for thought.
http://www.summitracing.com/parts/NAL-19244549
http://www.summitracing.com/parts/EDL-46383/
Last edited by 4mulafastech; 05-13-2011 at 12:59 PM.
05-13-2011, 02:19 PM
#28
Registered
In terms of cost Im going off what MAST is saying - 30K
And last I checked the LSM 550 goes for 25K
Those are basically turn key ready to roll.
Never had a crate motor work out for me, or anyone I know but Im sure they could. Neither of this crate engines put out what my backyard rig does, much less gets me to 600. (one is pretty close, but Id like to see a full dyno run for it.
IF you add accessories and exhaust and a new cam to prevent reversion(then you need a new tune etc) the price of these crate engines starts to climb pretty quick which is why the turn key offerings are 25 & 30K.
Is this list price- sure, but Im only in the market for 1 engine and should likely not get much off that price if any at all.
Im not saying that this packages aren't awesome- I think they are and Id love one in my littlle tunnel
Im just wondering if Im not just better off building a big block and being done with it.
In the meantime I'll be watching these new modern small blocks closely.
Uncle Dave
And last I checked the LSM 550 goes for 25K
Those are basically turn key ready to roll.
Never had a crate motor work out for me, or anyone I know but Im sure they could. Neither of this crate engines put out what my backyard rig does, much less gets me to 600. (one is pretty close, but Id like to see a full dyno run for it.
IF you add accessories and exhaust and a new cam to prevent reversion(then you need a new tune etc) the price of these crate engines starts to climb pretty quick which is why the turn key offerings are 25 & 30K.
Is this list price- sure, but Im only in the market for 1 engine and should likely not get much off that price if any at all.
Im not saying that this packages aren't awesome- I think they are and Id love one in my littlle tunnel
Im just wondering if Im not just better off building a big block and being done with it.
In the meantime I'll be watching these new modern small blocks closely.
Uncle Dave
05-13-2011, 03:31 PM
#29
Registered
Thread Starter
Regarding a big block for your little tunnel, I would be concerned about getting a bit tail heavy and losing some handling.
Whatever you decide, good luck and be sure to post updates. I always enjoy that kind of stuff.
05-13-2011, 04:19 PM
#30
I did the ls because I have a little 21ft wich is 6 ft wide and above all a good friend build these for a race class here in europe and knows them in and out .
It begin as alittle project to convert a outboard hull which I owned a long time and was given up and came along a never rigged hull and bought that to convert and put in a merc 6.2 or 496 ho but that should be quite heavy on the stern.
I bought the ls cheap on ebay and convert it whit my friend wich I enjoy and in the mean time I converted the hull wich was a big project due to the poor quality of the wood and stringer mounting ,so basicly I build almost a complete new boat .
The engine is a nice option for the smaller boats and make some nice power 450-500hp whitout big changes and $$$$ but it cost a lot of time to custom make a lot things .But is a nice replacement for a 5.7 , 6.2 or 454 in the smaller boats .
Closed cooling is a must due to the alluminium
The Mast and raylar engines are coming whit headers which is also a 4-5k wich is a option on other engines so Ray,s engine is arround 20K which is not much more then a new 496ho
It begin as alittle project to convert a outboard hull which I owned a long time and was given up and came along a never rigged hull and bought that to convert and put in a merc 6.2 or 496 ho but that should be quite heavy on the stern.
I bought the ls cheap on ebay and convert it whit my friend wich I enjoy and in the mean time I converted the hull wich was a big project due to the poor quality of the wood and stringer mounting ,so basicly I build almost a complete new boat .
The engine is a nice option for the smaller boats and make some nice power 450-500hp whitout big changes and $$$$ but it cost a lot of time to custom make a lot things .But is a nice replacement for a 5.7 , 6.2 or 454 in the smaller boats .
Closed cooling is a must due to the alluminium
The Mast and raylar engines are coming whit headers which is also a 4-5k wich is a option on other engines so Ray,s engine is arround 20K which is not much more then a new 496ho
