At least yours is spinning Bro! I haven't been in the boost yet. My freakin headers were spitting water and making the O2s go nuts. I guess i'll have to spend another $3k.

Kenny,My lightnings started reverting water when I went to the cam and afr heads that made 950 hp vs the 750 hp set-up on my 540,I switched to stainless marine 3's. They are big and ugly but they don't revert,are you headers leaking or reverting? When I talked to Jan at lightning he told me the lightnings revert water as bad or worse then stock manifolds,keep this in mind if you have went up a size or 2 on your cam from before,Smitty

I see you already have lightnings,if you want to switch to stainless marine3's I have a good friend that can sell them close to dealer cost,give me a call on my cell,you have my number,Smitty

Donzi,

The answer is yes on the running closed loop all the time..

1. As far as optimal fuel burn, complete control of the engine allows you to do just that.. I am compromised at Dual Widebands.. I would also like EGT's on each cylinder, but don't want to custom build dual walled headers myself.

2. Things do not get funny as HP creeps up if you have the ability to tune for the variables..

3. Defying Physics is not possible.. Quantum mechanics is a perfect example of things being explainable that are considered impossible to explain.. A little 500+ CI motor is not that difficult compared to some other things like nuclear power..

4. In order to get more fuel flow at higher power levels, it is not a neccessity to have bigger injectors....! (I will let you figure that one out, as I do not want to give it all away. There are several ways to do this.)

5. Flow requirements are not linear.. Yes, you are correct, but a multi variable input/output matrix can resolve this. All those load and variable sensors on the engine combined with the software are there for a reason.

6. Boost for me is only relevant to the amount of heat it generates. I care more about mass airflow, and charge density. Boost (pressure) is resistant to flow... look it up.. I want less BOOST # (PSI) with MORE AIRFLOW (CFM) this gives INCREASED CHARGE DENSITY....

7. The whole idea of tuning in closed loop is to be able to control the variables of the engine input and resultant output as a function of load.. The EFI engine does not care if it is bouncing around in a boat, car, truck or otherwise.. A carb motor does, as the carb is affected by motion.

Thanks for the idea compliments... I think this is a simple project compared to other things I have done. The biggest problem I have was finding people to do some things for me that I wanted done to MY specifications, and not theirs, or what they learned, thought, or head from someone else.. I did however find some people like this.. One guy in particular, and things are coming along great.

The idea is a little out of the ordinary, but it's actually pretty simple.. The thing is that all the components will be matched as best as possible, and then tuned accordingly.. Maybe once I get a bit further along I will change some things.. I already have some other ideas to improve the original design..

On the fuel injector question in #4 above.... Why can't I run another 8 additional injectors, or build the motor to be at .45 BSFC, instead of .65 BSFC... Either way, I can use smaller injectors to make more power....

You have to think out of the box, but remember the basics... Stop reading all that advertising that I rant and rave about..!

Hope this helps... And it's fun when it's not left aone, as we all learn... Keep it coming..

R

I would think that with the right tuning anything is possible. I would think that turbos would be even harder to tune will than a centrifugal blower.

I like the more injector idea. I guess that you could build some custom rails.

Are you thinking about staying away from a batch fire system like a MEFI and going with a sequential MPI?

What kind of exhaust are you thinking about since the marine environment is murder on O-2 sensors? I think that one of the outboard companies has mastered that one.

I still think that if you are going to all of that trouble you may want to consider a bigger blower. The cost differential is not that much especially once you get into custom injection systems. Whether you are building boost or moving air, it will not be a bottleneck.

I like different projects. I tricked out a V-6 in a little 16 foot Donzi. Everyone told me I had to go to a V-8 if I wanted speed. I ended up with speed and better handling and yes, 200 lbs in the back of a 16 foot boat does make a difference. Several have done the small block thing but I only know of one other that has done a 6. I am still not done with that one. I think that with a blower I can build a fast 16 that will not chine walk like the other 16's (or at least not as bad).

Running open loop in a marine application, with the current 02 sensor technology is not a great idea. With moisture, water rich a/f's, the sensor starts to lose accuracy. Even if you have the high/low ranges pretty tight, if it gets too far off, you can end up with some expensive ash trays. You may think there is no water, but when that motor starts up the first time, or refires from cooling down while you hung out for awhile, or you backed up and hit a wave at the same time, etc.

I would recommend using it to get the calibration done, then remove sensor and run it. If you leave that sensor in, there is a better chance that it will not be accurate vs. the other way around.

Dustin

Heck, most folks I know are lucky to get a few runs out of them and that is not with the biggest cam in the world and that is not condensation that would result from leaving them in overnight.

Is there any secret to making them last while dialing in a boat?

Dustin & Donzi,

Maybe you guys are confused on open VS closed loop. I will be running closed loop..

About the comment on moisture.. If an O2 sensor can survive in an automotive application in the arctic, scandinavia, antartic, and other such environments, why would it not survive in a boat?

As far as water getting into the system, I think that is bad design. If the header is sealed as it should be, and installed with the correct height and angle, then there should be minimal if any reversion. If the header is leaking, then that's a separate issue. I will be running the Exhaust with the Formula ST platform (slightly modified), and not direct through hull with flappers. So far, after 330+ hours, no reversion problems with stock risers that have a smaller incline than the CMI setup going into the boat.

Regarding the comment on the cam being used is too big, then also not too good, and a design issue.. I think there are ways to optimize flow without excessive lift, overlap, and or duration. (I have been asked by my engine builder colleague to avoid revealing our specifics for now, and agreed, so I will have to say that you guys can feel free to research it, as the info is available to the public. I can't comment on exactly how we are going about it.) It's about flow, and efficiency of the mixture, as well as tuning the system, and not neccessarily just big duration that counts...

Like I said earlier, there are ways to solve these issues. I agree that there are some limitations with an O2, but not to the point to not use the O2 sensors.

I of course can't speak for others, but I've seen race cars run in extremely harsh environments compared to general marine use, and their O2 sensors live just fine.. Heck, Saab, Porsche, Volvo, Mercedes, GM, Ford, and others sell and test cars in Finland and Norway in the arctic circle, and the Bosch O2 sensors do just fine in that horrible cold wet Scandinavian winter, and the heat of their summers, so I don't see a problem under normal conditions unless the exhaust leaks..

Thanks for the comments....

To give some credit on not using the Dual wideband O2 sensors, Like I said earlier, I would like to use EGT sensors.. I am compromised by using dual O2 sensors. Ideally, I would really like to use both EGT's and O2's.

There may even be a workaround on the EGT to get cylinder temperatures or pressures, but I am still checking it out..

In my ideal engine, I would want to know the value of pressures and temps in the cylinder, and also to be able to control it as a function of load on the fly in individual cylinders.....

Makes sense...?

R

Oh I know the difference between closed loop and open loop.

I also know that there is a big difference between what is happening in the exhaust system in a Volvo in Norway and a boat in California. I also know why the stock 496 with a mild cam has a catch plate for the condensation (heck, it even has a name for it, but I forgot). I know that while your Formula is not really reverting water, it more than likely does have condensation in the exhaust system and probably a bunch more than a Saab has in its upper exhaust system in Sweden. I know why you don't take what works on an oval track and use it in a boat. I know why tons of automotive principals should be thrown out the door when dealing with boats.

Do I think that there is room for exploration and advancement? Absolutely! I would love to see someone pull it off.

I don't think that it will be easy. I have seen a very experienced engine builder wrestle with EFI issues on a dyno. I am no engine builder but I do know that if it was easy, they would be doing it.

Blue 242,I wouldn't EVER build a 750 or 950 hp marine engine and count on 02 sensors working 100% of the time to give the right feedback to the computer to keep your af'rs correct,erspecially under boost. There is a reason NO marine manufacturer has done it either,its not that they don't want to. You may have some "secret" ideas or plans for a special camshaft but pure and simple you will not make the kind of hp numbers your talking about without some extra lift/duration and over lap,espeically in a "588". Along with increased cam size comes increased reversion issues,period. The slightest amount of moisture will kill your 02 sensors,we are not talking about leaking headers or enviromental issuses.
As far as running bsfc's of .45 on a blown 588,(or basically your trying to say you feel your going to try to run afr's to the effect of about 14-1 to15-1, even with the best piston coatings/ceramic plasma crown coatings,chamber coatings etc (I'm running them myself,your not the first one to think of this) and even the trickest innercooler with some degree of subcooling (if you can achieve this),its still not going to stay together under any kind of wot/boost/load condition. By doing everything right and "perfect" and avoiding sustained wot operation you might get away with afr's slighly higher (mid 12's low 13's).
I'm going to give you a couple friendly suggestions-
When you order your custom pistons, order some extra ones,the lead time can hold up your valuable boating time and when,not if, you melt this badboy down you'll have spares on the shelf,no waiting to get it back together(Dick Tryce does this,I'm serious).
Don't RENT a cherry picker or engine crane for removing/installing your motor,BUY one,you'll probably be needing it more then once,Smitty