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harbormaster
04-15-2009, 09:56 PM
I worked late tonite on my newest project. This is bare LS block that we are test fitting everything on before dressing out the LS3. I thought you might enjoy these. We will be testing with it in the 22 classic when its done in a few weeks. For the record. It will weigh 500lbs , naturally aspirated and be 518hp with a redline of 6500 rpms. It will include CMI headers, billet serpentine system and closed cooling for 16k. This price includes your choice of color paint and/or anodizing.

We moved the coils off of the valve covers to the back of the engine. I then worked with out machinist to put our company logo on the valve covers. I believe there will also be a set of valve covers with "Donzi" on them as well :biggrin.:. If anyone wants one let me know. Scot V.

The Hedgehog
04-15-2009, 10:00 PM
That looks like a bunch of fun to have in an 18 or 22!

BUIZILLA
04-15-2009, 10:01 PM
reversed cooling?

harbormaster
04-15-2009, 10:10 PM
We built a custom heat exchanger for this engine. hose fittings will be be pressed on stainless fittings. No hose clamps on this puppy. We will probably be using a smaller tube header on this engine. The smaller tube supposedly performs better with this engine when naturally aspirated.

CJmike
04-15-2009, 10:25 PM
That motor looks great. But could somebody please explain the carb thing for me. I just don't get it. The marine world seems to be holding on to carbs but everyone else has moved on. I know I am just a simple 4x4 guy that got into donzi's but even back woods 4x4 guys run fuel injection these days.

I do really like the look of that motor. Two of those inthe back of a ZX would be pretty dang sweet.

mrfixxall
04-15-2009, 10:31 PM
That motor looks great. But could somebody please explain the carb thing for me. I just don't get it. The marine world seems to be holding on to carbs but everyone else has moved on. I know I am just a simple 4x4 guy that got into donzi's but even back woods 4x4 guys run fuel injection these days.

I do really like the look of that motor. Two of those inthe back of a ZX would be pretty dang sweet.


More hp out of a carb:)

harbormaster
04-15-2009, 10:33 PM
Very simple. The carb version of this engine is very simple and a lot less expensive that fuel injection. Our goal was to build a high horsepower engine at an affordable price. Mercruiser's 525 dealer cost is 36000 dollars!

Look in the GM performance parts catalog online. The fuel injected engines with more horsepower than this one were all supercharged. I know, I know . It does not make sense to me either.

Our first Fuel injected offering will also be supercharged.

CJmike
04-15-2009, 10:40 PM
More hp out of a carb:)


Thats a crap answer show me a top fuel dragster with a carb.

I'll totally buy they are cheap answer. But when is a Donzi cheap?

VetteLT193
04-15-2009, 11:08 PM
Thats a crap answer show me a top fuel dragster with a carb.

I'll totally buy they are cheap answer. But when is a Donzi cheap?

show me a top fuel dragster that runs on gasoline.

I'm an advocate for fuel injection, but in a boat it can be a pain in the ass. and that is just the beginning

EFI on a stock engine is a good idea... HiPo you are in somewhat uncharted territory. And money does matter. What are you going to do if the guy next to you, who spent the same amount of money, blows by you in your fuel injected boat.... yell a him as he passes and say, "But I have fuel injection!"?

harbormaster
04-16-2009, 05:26 AM
Other point. The carb engine has a cleaner look that the plastic looking crap GM puts on their engines. with the package we are building. The extra 2000 bucks for efi system and 1000 bucks for reprogramming was just not worth it to us right now.

Yeah and efi is soooo good that mercruiser locks down the ecm and you cant do **** with it. you have to throw away thousands of dollars of "better efi crap" and start over. AND THERE IS NO AFTER MARKET PERFORMANCE PARTS FOR MOST OF THE EFI MERC SYSTEMS OUT THERE. EVER WONDER WHY?

just like solar is better than coal, but we do not use it. I don't have to tell you the answer to that onE...

BlownCrewCab
04-16-2009, 07:07 AM
I think he was getting at, That this (LS Based Motor) Makes more power with a carb than it does Injected. and he's right, it does. But GM can't control emissions with a carb.

He didn't mean that carbs where faster Than supercharged dragsters.

gcarter
04-16-2009, 07:26 AM
[quote=CJmike;507537]Thats a crap answer show me a top fuel dragster with a carb.quote]

Oh, I can't resist!:rlol:

CJmike, where's there any similarity between your statement and the real world?
Do you want a boat that'll idle and run slowly?
Do you like boats that have just two speeds, on or off?
There's this thing called "drivability" that I'm sure you want in your projects as much as HM.
There's plenty of aftermarket FI systems that're completely programmable. I'm sure HM will be glad to supply an engine w/one and even offer the programming services. Just ask him.
But the price just went up to $20K+.

I really agree with your sentiments, but the state of the technology is just not there yet w/o a lot of additional expense.

CJmike
04-16-2009, 08:00 AM
I agree with the expense part but 20K for fuel injection? When we started putting them in off road they were expensive at first but the more people that embraced it the cheaper it got. Part of the problem is lack of acceptance is keeping prices high. The mercruiser system is pretty simple. The problem I found is very few program it. Used to be the same with any of the car stuff as well. Now I can get my offroad motor custom tuned on the dyno for $500. If the boat stuff was there I am sure more people would embrace it. But its kind of a catch 22. People don't do it becuase its expensive and shops won't do it becuase there is no market.

Fuel injection should run better than a carb in any given situation. The top fuel comment was just tossed in there becuase, the carbs make more HP comment. Those guys are making more HP than just about anybody, if carbs truly made more HP, they would run them. I know its a throttle switch in those things for the most part. But the comment wasn't about driveability it was about HP.

The Hedgehog
04-16-2009, 10:02 AM
I an an EFI guy and can see both sides. I am ok with a carb on the intro model. I have been in plenty of carb boats that run almost like an EFI boat when setup right. Plus, one could buy the carb and always upgrade to an EFI later without too much work.

mrfixxall
04-16-2009, 10:06 AM
Thats a crap answer show me a top fuel dragster with a carb.

I'll totally buy they are cheap answer. But when is a Donzi cheap?


Their not efi,their mechanical fi....change a pill and hang on:)BTW show me a boat that you drive every day with a 6000 hp blown nitro injected motor:)that you have to have two fuel tanks because you cant start the engine on nitro:)


Scott looks nice btw,how come you didnt go with the lsx block?

HallJ
04-16-2009, 10:43 AM
Their not efi,their mechanical fi....change a pill and hang on:)BTW show me a boat that you drive every day with a 6000 hp blown nitro injecter motor:)that you have to have two fuel tanks because you cant start the engine on nitro:)


Scott looks nice btw,how come you didnt go with the lsx block?


Weight? Expense?

harbormaster
04-17-2009, 07:28 AM
This one 518hp with the CMI headers and closed cooling complete weighs in at 500lbs and sells for 15,900.00. (approx 400lbs less than a 454!).

This engine is based on the LS 376/515, an upgraded LS3 that has a more aggressive hydraulic roller cam and GM's new carbureted intake manifold.

The new GM carbureted intake manifold is specific for the big flow L92/LS3 cylinder heads.

I was at a show yesterday and The owner of American offshore showed an interest in these for his cats.

MOP
04-17-2009, 01:50 PM
Very nice will be pleased to hear how well it does, I am also a fan of simplicity! My last 4X4 was EFI, it died in the wood and I was screwed. I bet if it was carbed I would have found a way to get out on my own. Another thing that bothers me about injection is the instant start, I like my engine to roll over a turn or so to let some oil get to things. My thinking may be all wet but it is my thinking, if I had injection on mine I would do what a few others do pull the lanyard and crank it a few turns or have a dash ignition kill which was mentioned up here. 90% of engine wear is on start up!

Phil

osur866
04-17-2009, 06:21 PM
I'm keeping a close eye on this, I sure wish someone would put this in an 18 and report back!!! Steve

mrfixxall
04-17-2009, 07:51 PM
Very nice will be please to hear how well it does, I am also a fan of simplicity! My last 4X4 was EFI, it died in the wood and I was screwed. I bet if it was carbed I would have found a way to get out on my own. Another thing that bothers me about injection is the instant start, I like my engine to roll over a turn or so to let some oil get to things. My thinking may be all wet but it is my thinking, if I had injection on mine I would do what a few others do pull the lanyard and crank it a few turns or have a dash ignition kill which was mentioned up here. 90% of engine wear is on start up!

Phil


Good point mop,,as for a starting solution im gonna install a ole starter button...

BigGrizzly
04-18-2009, 10:02 AM
Like George I can not resist this either. Working for a auto manufacturer and working with a formidable engine builder who helped design the Motortron system and thinking of upgrading, my own trouble free 502. As I am doing my engine I asked Garry If I should go that rout because it would be better- He told me different , expensive but NOT better. In the auto side We went to fuel injection for one it was cheaper to maintain the emissions standards so thar we have an all altitude car instead of three engines. All are O2 sensor ECU controlled. In our marten engines we are one of the only ECU O2 sensor controlled applications that work. In the boat application it is not a change in driving application like a car. As for the drag race thing, The engines run for only seconds in in what is called a mean lean situation, which gives the most power and shortest durability. So CJMike your jumping into a hornets nest at this time in history. Maybe in some years down the road it will be OK but today it isn't. But what do I know my blown carbed 502 engine only has 690+ horse power and has been together for 800 hours, with only a starter and blower belt failure. So to convert mine over would be an additional $3,000+ to start. then another 4 hours of dyno time, need I go on. ON another note we built and dynoed a twin turboed LS engine to 1,243 HP with 15 psi of boost. this engine goes into a drift corvette and will be a semi daily driver car.:eek::biggrin.: The ECU took 4.5 hours of dyno time to get there. It started with 757 HP.
Scott this is a nice project and if it were me I still would go carb tor THAT application. One of the my main reasons is since I came from the Muscle care era and injected engines are just plain ugly and over kill. The other truth is that I will not get into the carb vs injection HP thing because there is a fuel injected carb that really kicks arse.

Carl C
04-18-2009, 10:28 AM
You guys are on thin ice turning Scot's engine selling post into a debate on EFI vs. carb;). I would start a new thread for that.

Is this a small block motor? What are the cubic inches?

handfulz28
04-18-2009, 02:41 PM
What's the dyno chart look like? How flat is the TQ curve and where are the TQ/HP peaks?


Carb vs EFI = old farts vs young guns
Nothing more than fear of the unknown keeps builders from using EFI. There's waay too much R&D sunk into EFI to make me think it's no good for marine use; there's just not a lot invested by marine builders other than the two or three well known builders/programmers. And there's plenty of engine builders using production based EFI engines with perfect results. Not to mention custom builders using aftermarket EFI with great success.

Heaven forbid somebody has to let go of 50years of Holley charts with countless Main jet, Secondary, air, power valves, float levels, etc. and learn air flow, pulse width and O2 readings. Oh, you have to bring a computer on the boat....oooh....voodoo....:kyle:

"I wish my EFI didn't start so quickly" :rlol:
Funny, but my carb'd motors fire just as crisp as an EFI motor. One pump set the choke, can hardly release the key before she's on her own.

Apologies for the rant on HM's build thread. I'll go back to helping my GF write her ECO paper arguing that CEO's aren't overpaid but teachers are...:eek:
:biggrin.:

BigGrizzly
04-18-2009, 08:05 PM
Well, well we all can all send our ECUs to Hanzful28 to get fixed, and reprogrammed.

Last Real Texan
04-20-2009, 06:20 PM
Scott...looks great ! am looking forward to the results....I know of a 28 ft Cig that needs a pair of these in it.

Tex

harbormaster
04-26-2009, 02:36 PM
We made a few changes to the base engine that take it from 515hp to 625hp.
It is also now 441 cid instead of 376 cid. This added 1500 bucks to the final package without losing drivability or reliability.

osur866
04-26-2009, 11:34 PM
Nice, when is it going in a boat for testing? Steve

MOP
04-29-2009, 06:36 PM
We need more pics to drool over!!!!!!!!!!!!!!!!!!!

harbormaster
04-30-2009, 10:56 AM
currently Building the "Dyno Dog" for the dyno run. I will post video and sound of the Dyno testing when done.

harbormaster
05-03-2009, 12:42 AM
Should finish dyno testing in 2.5 weeks. I have one sold to a guy who is building a new boat. More details when things are finalized. I have been contacted by 2 different boat builders who are done with Mercruiser.

Looking at mating it to the new conrad bravo replacement that is rated for 800hp if we can come to an agreement on a real world price

MDonziM
05-29-2009, 06:05 AM
Have you used these carbs before? Curious if you have experience with them. Finishing up a 540 build and put a 950cfm version on . Looks to be well thought out with the 2 bowl level view holes, billet stuff, and of course the red factor.

Sweet looking motor btw, love the power to weight.