LS3 engine coming together

[harbormaster]

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 . If anyone wants one let me know. Scot V.

[The Hedgehog]

That looks like a bunch of fun to have in an 18 or 22!

[BUIZILLA]

reversed cooling?

[harbormaster]

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]

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]

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]

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]

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]

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]

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]

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]

[quote=CJmike;507537]Thats a crap answer show me a top fuel dragster with a carb.quote]

Oh, I can't resist!

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]

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]

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]

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 onBTW show me a boat that you drive every day with a 6000 hp blown nitro injected motorthat 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?