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4mulafastech 05-02-2011 06:18 PM

Best I can tell...

545 ft*lb peak torque at 4400 rpm
551 HP at 6100 rpm

rmbuilder 05-02-2011 07:21 PM

1 Attachment(s)
Bor,

Attached is the full conversion from Nm/Kw to Lbs_Ft/Hp. Can you tell more regarding the displacement and other particulars.

Bob

bor 05-04-2011 11:14 AM

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 .

Uncle Dave 05-12-2011 11:09 PM

2 Attachment(s)
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

4mulafastech 05-13-2011 09:25 AM

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.

Uncle Dave 05-13-2011 11:37 AM

2 Attachment(s)

Originally Posted by 4mulafastech (Post 3402214)
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.

The aluminum block would help and I guess If I spend 4K I can get that as well,

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

4mulafastech 05-13-2011 12:40 PM


Originally Posted by Uncle Dave (Post 3402343)
Yes the torque curve is impressive on those mills, but it doesn't seem 20K better than my garage special.

---thoughts?

UD

With all things being equal, I don't think we are looking at a 20K difference. It would be interesting to know what the actual cost difference is if using the same accessories and EFI system. I suppose you could build your own LS and put a carb on it as well.

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.:drink:

http://www.summitracing.com/parts/NAL-19244549

http://www.summitracing.com/parts/EDL-46383/

Uncle Dave 05-13-2011 02:19 PM

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

4mulafastech 05-13-2011 03:31 PM


Originally Posted by Uncle Dave (Post 3402458)
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.

Gotcha. I guess my point was the cost a traditional small block of similar horsepower back yard built with EFI, CMI headers, electronics, accessories, etc..., essentially a turn-key package is not 20K less than Raylar or MAST. I wonder what a back yard built LS combo (carbed) would cost(?).

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.:coolcowboy:

bor 05-13-2011 04:19 PM

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


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