HabanaJoe

Njawb,

I'll give you my reasons, I can't speak for anyone else. The Duramax has been out there for a while and even someone on OSO has tinkered with it and not got it to market. All the people that are close to bringing it to market have not yet done so - why?

In my opinion I see only two reasons:

1 - no real market for it, so stop throwing good money after bad

or

2 - they can't make sustainable and reliable Hp, again a drag truck, salt flat truck in my opinion just toys that are great for PR for selling pick-up truck parts but can't equate to a marketable marine product

Now Audi running at leMans, that's real, no smoke and mirrors, either the car kicks butt for 24 hours or they are DNF's

Why if I were to do something for real, would I want to follow in someone else's foot steps??? I would want something that is smaller, lighter, more high-tech, higher reving with less effort than a Duramaxx. Otherwise I'm competeing in the same space with nothing different to offer?

I understand several people can use the same base engine and market it under different names but don't you think customers realize that?

I have more to say on this but I'll give you a chance to fire back first!

Joe Gere

Njawb

Other than more high-tech, the Audi V12 is none of those. I've also got to believe that it is considerably more expensive than the Duramax, which cuts considerably into your marketability arguments -- if a marine Duramax really isn't marketable, then a marine Audi V12 is probably less so.

While it hasn't been as high-profile an effort as the racing Audi V12 TDI (which is quite a bit different from the consumer V12), Banks has been endurance racing (or at least preparing to do so) with the Duramax. They had transmission problems before they switched over to Pat's 6-speed, so maybe he can tell us more about how that effort is going.

In all honesty, it sounds like your reasoning mostly amounts to wanting to do something different, but cost/benefit-"bang for the buck"-"return on effort" arguments are currently hazy at best, and may fall on the side of the Duramax. If nothing else, I'd want to have something much more concrete than just your suppositions as to why marine Duramaxes are not on the market in quantity before deciding that such engines are not a viable option.

I really don't understand your comment about marketing the same base engine under different names. Yes, Mercury builds BBCs, as does Crusader, and many custom marine engine builders. Do you really think customers can't tell the difference between one of JCPERF's engines and a 496 Mercruiser? Or are you worried that you (we? who or what kind of company is supposedly building and selling this engine?) couldn't build a Duramax-based marine engine that is better than anyone else's?

Njawb

To follow up on your prior request, Joe, I don't know of any publicly available dimensioned drawings of the Audi engine, but this is a pretty good write-up that shows you a good deal of what goes where.

HabanaJoe

So how much less does a Durmaxx weight?

How much shorter is a Duramaxx?

How much higher does a stock Duramaxx rev?

How much cheaper ido you think a Duramaxx is? (this one you can't answer because no one will give you OEM pricing) (my opinion is VW may build more V10 diesels globally then GM does it's Duramaxx?)

Your last remark - "Or are you worried that you (we? who or what kind of company is supposedly building and selling this engine?) couldn't build a Duramax-based marine engine that is better than anyone else's?"

That to me implies that we would have to do more than everyone else to build a better Duramaxx - correct? Than maybe that will make our costs escalate to the point that useing a better base engine (or more expensive base engine) might be better in the long run?

I know you like to take shots at me with your hazzy remarks and so forth and I allow you to in the spirit of discovery - I just consider it all in good bantering (if that's a word?).

But, I don't see you doing much more than answering me with supposition as well?

I know I'm opinionated, pompas, don't like to listen to others and so forth. I paid my money to get here, I would like to know who you are and your background as I've made mine pretty open on here so far.

Joe Gere

ps - YES, I like to be different, I never want to wake up and look in the mirror and say "I could've, should've". I take risks, want to be the first at everything, not proud of this but have several brankruptices under my belt, failed IPO as well as selling sucessful start-up companies to Fortune 100 companies.

The APBA wrote rules around diesels in sportsman class racing just so I could race - no other reason than I want to be different

Njawb

Hard to say, since I haven't been able to find authoritative figures published for either engine, but the overall dimensions are very similar, both are iron blocks with aluminum heads, and the non-authoritative sources/guesstimates/rumors place both of them in the 800-900 lbs. range -- effectively the same as a BBC. My point isn't that the Duramax is definitely lighter and shorter (it may be slightly so, or the Audi may be a few pounds lighter and an inch or two shorter -- I don't know for certain either way), but rather that there is no significant difference between the two.

Stock Duramax doesn't rev higher. The published peak horsepower and redline figures for the Audi are all but the same as Banks claims for their modded Duramax. The stroke of the engines are almost the same (91.4mm for the Audi, 92mm for the Duramax), so piston speeds will also be the same. Do you think controlling the Duramax's pushrod valvetrain at 5000 RPM would be a problem?

No idea. Though even if the production costs of the engines were the same, you'll be facing a huge foreign exchange penalty since the dollar is currently so low against the euro.

Yes, if your business plan is designed more around superior product than superior service and other non-performance-engineering concerns.

Maybe. That's the kind of thing you'd need to do some hard number crunching on before making a decision for one base engine over the other. I haven't seen those kind of data or that kind of argument made -- only hazy suppositions and hand waving. That is why I questioned whether the Duramax was being dismissed out of hand and prematurely.

It's not a shot at you; it's a shot at the current state of our knowledge and the lack of hard information. Yes, my data and arguments aren't much if any firmer -- but then again, I wasn't the one declaring that we had already narrowed our selection down to two engines.

I'm not attacking you personally, Joe; and I respect your past engineering accomplishments. What I am doing is questioning this informal design process and decision making, because it seems pretty loose. Maybe that's all you want, some space to have fun blowing off a little hand waving steam. Myself, I'm a software engineer, and thus afflicted with a propensity to question assumed preconditions, invariants, exceptional cases, and the like to the point of nit-picking -- I even have fun doing so. Software engineering is extremely unforgiving of even tiny mistakes, and I'm accomplished in my field; but I have only intellectual interests at this point in performance marine diesels. I certainly don't have any financial stake in producing marine diesel product, nor do I anticipate having any in the future.

Satisfied?

HabanaJoe

Ahh, this is good I will pm you later for a good reason.

I understand software, one of my businesses was internet databases and we sold that to a $12 billion company.

I think when your pioneering anything on a limited budget as we have always done, trial and error is a big part of it, especially with software for us anyway. I don't think you can dismiss that as loose engineering. I've been in the Navistar and Cummins design/concept centers (years ago) and if you think they are hard core engineers your wrong, they played like I did. The software that exists today just wasn't available to anyone including Cummins in the 80's to only bench run a 3D model and not spend money to destroy some iron in the course of research!! I doubt Banks doesn't do trail and error as well, otherwise their engines would be right the first time and be in the market.

I know Banks from back when, Banks used to make our aluminium exhaust manifolds for the Navistar 7.3 L diesel. In those early days all diesel hot rodding was hunt and peck based on some experience as to how a gas engine reacts.

I think you under estimate gut feeling, my gut says Audi or VW are more global companies, Audi with it's racing diesels I think is huge from a PR standpoint, much more so than the Banks name. I also think the overhead cams are better for higher reving diesels. The high boost pressures in a souped up diesel want to hold the intake valves open, you need big springs to hold back 50 or 60 psi!!!! This kills the valve train, makes the valves hang open like crazy, generally with big boost you have high exhaust pressures as well - again valves do't want to close!!! This is a much different dynamic than you see in a gas engine where the higher rpm's causes float because the springs can't push the retainers back fast enough to catch the valves. Valves slap the rockers and stress out everything, valves want to hit pistions when they hang open - all bad.

So, yes I think the overhead cam can control that better

If I were to spend money and play I would look at those two engines from the standpoint of Audi has great worldwide press through racing, VW has a great rep for solid engineering and both companies PR wise don't have disaters on their hands with diesels.

GM on the other hand still has a bad rap from several failed attempts to put diesels in pick-ups and cars. The early 5.7 the later 6.2 both not the greatest. Even here os OSO the debate wages should I get a Ford, Dodge or Chevy diesel and who's is better? Over the long run both Ford & Dodge have proven themselves to be a more consistant player in the diesel p/u truck market - I don't think you can dispute that?

How many people including myself would never buy a GM diesel p/u? I owned both a 5.7 & 6.2 as service trucks and they sucked. Yes, the 6.2 trans was too light duty and the engine too little power, but overall it gave it a bad name in the market just the same.

So, in my mind when I look at a project I think about more than engine itself, hence the reason why something needs to bolt to a Mercruiser and work. If it can't you will loose over 90% of the sterndrive repower market, people don't want to modify their boats (physically to fit an engine), the value goes down when you do that because you can not recoup those costs.

Am I making sense?

Jassman

there is no replacement as of now..I am waiting for the Cummins 480 that will be turned up to 600 (shortened life span) to hit the market..along with that being able to couple that with Merc drive package..

I am curious to the Duramax..but will wait till they are out before I make my decisions on which way to proceed.

Jeff

Njawb

Some.

Don't get me wrong, I am certainly not against the Audi or VW engines. Both of them have some real advantages over the Duramax. I'm just not yet convinced that their disadvantages (which are almost entirely related to availability and pricing) aren't so great that the Duramax doesn't still come out ahead. For all three base engines (and any other contenders) I think there are four essential questions:

1) Is it available? If you can't even get a quantity of the base engine from the factory, then further discussions are at most academic. My sense is that the Duramax is more available than either German engine at this point.

2) Are the performance goals attainable with this engine? Beyond the package size constraints, the first order goals I am thinking of are basic torque and horsepower ratings. In hot-rodded, non-marine form the Duramax can exceed the performance goals. Announced but not yet available consumer marine Duramax engines are very close to our basic performance goals. The VW and Audi engines in mass-production automotive form are about 20% or more short of the goals. How much faster and under how much more boost to you anticipate running the VW or Audi? Are we reasonably certain that the performance goals can be met with either of these engines?

3) How much will it cost? This one breaks down into two sub-questions: a) How much will it cost to produce? b) How much will it cost to run and maintain? For all three engines, these are all big unknowns to me.

4) Will people buy it? A lot of that depends on how the product is positioned and marketed. I can see the Audi in particular becoming a successful boutique engine aimed at the cost-is-almost-no-object boater. I don't think the Duramax will ever be a sexy, drooled over engine. On the other hand, if it costs significantly less to purchase and not inordinately more to run and maintain than the Audi, then the Duramax could conceivably sell in a broader market than a boutique Audi engine.

Am I making sense?