Check these heads out!
 

Go to www.araoengineering.com and check these heads out! They are claiming higher hp and tq with a lot less lift and duration and they say they are very resistant to detonation. Sounds like it would greatly increase reliability and performance across the board! They are claiming a N.A. 1000hp LSX based small block is possible with even more from a big block!

Engine guys please share your thoughts on these.

My first thought was camshaft(s). It appears one lifter opens two valves. Interesting concept. I would think it could work very well.

Cost versus Benefit & Reliability Ratios??
 

These type of heads and the 32 valve single pushrod variant also. The real problem with using them on marine performance engines is: (besides the "Cool" factor)
1. Get the price for a pair of big block with all hardware and valve covers and the price will "knock your socks off"!
For this kind of money any good marine engine builder can take more affordable aftermarket heads and make you an engine of comparable HP and torque! One we know will last and be reliable!
2. Every application would require a custom intake manifold, just another $3-$K.
3. Who has a dyno report on a big block with marine type (non-race) setup with regular pump gas type set-up.
Can't compare racing applications to marine performance usage, different animals.
4. Have any of these big block or LSX units been used and documented in any endurance (long hour) applications. Again Bonneville Runs and drag racing won't cut it in a performance boat.

Surmmarizied:
Its somewhat easy (fairly inexpensive) to take any good small block, big block or LSX type build engine and make big horsepower numbers, Done hundreds of times everyday all over the World!
Can these heads be used on a reliable durable marine performance engine for long hours of sustained use?
I don't know, but there will be very few willing to spend the extra dollars and time to experiment and find out!

Nice to look at these specialty parts for limited use but you are better off saving your money and buying a good overall engine package thats proven!

Also noted that these type of threads seem to pop up from time to time from almsot non-existant posters like your self (2 previous posts) Wonder if people are playing with posts to generate posting counts?? Humm??


Best Regards,
Ray @ Raylar

well said Ray!

Raylar, with all due respect I couldn't care less about my post count. I posted the info because I thought it may be of interest/benefit to the boating community. The engineering behind it seems sound as does the test info provided. Running significantly less lift, duration and spring pressure should translate into increased reliability due to less wear and stress. The fact that they flow MUCH more air than any two valver can is icing on the cake! They are machined out of billet aluminum so the strength/quality should be there also for the long haul.

As for cost they start at $10K complete...not much more than a good set of ported aftermarket aluminum heads which will still flow much less air.The down side is the custom manifold (which they will build also). But judging form the price of the complete heads one would think this would be reasonable. If they prove to be much more reliable how many times can you overhaul conventional heads before you are way in the hole cost wise compared to spending for these from the start? Not to mention what more time on the water and less in the repair shop would be worth to most people.

For the record I have NO ties to this company, just thought they had a product that may have significant potential for the boating community and wanted to share and do my part to advance the sport. That is my only motivation here!

Ray, I don't know you or don't think I have ever met you but I will say that almost every post I see from you is pretty negative. Especially if it has to do with SBC advancements. Not sure why you would be so defensive about new and different things. You sound like my Dad who is getting pretty old and stuck in his ways. He still thinks mechanical injection is the way to go, who needs those stinking computers.

These LSX heads look pretty impressive especially with 405CFM flow rates. And don't give me that expensive line, every new technology is expensive at first, plus its not like you are selling "cheap" stuff.

it cost money to push the envelope and do new things. I for one am very interested in the New LSX platform and these heads. Looks like a pretty good way to move a lot of air.


MP

Looks To Be A Very Neat Concept. Hope It Works Out

well said you cant steal secound base standing on first

Forced induction is better,,:drink:

the valves we just bought for dennis are $160 apiece. that would suck having to buy two more sets of those.

If the heads could be reliable and add 200hp over a conventional head, f' the blower!!!

4 valves per cylinder are on the majority of all new engines and it also helps considerably with smog. I give them credit and wish them the very best!

Sorta like electronics.... Plasma TV's were super expensive when first made but now they're almost as much as regular top of the line flat-screens!!! ;)

I looked at them about 2 years ago. They are definitely cool looking. It is an excellent concept that we know works (4.6L modular Ford, etc) I would be really curious to see how well they hold up over time. Ray brought up some good points. There are easier ways to make the power, but I am not saying it doesn't work. I would love to use a set, that is why I looked into them.
Someone in my position needs to either talk a customer into forking over the cash to try them with no guarantees, or spring for them myself and try to make it work. Not many guys want to take a 10-15K gamble when there is something else that we know works. There is lies the problem. It is very similar to building a 750+ ci engine. You could just as easily build a 598 ci with a Whipple and have a turn key piece with off the shelf parts, not something that has a bunch of one off, custom made parts. Again, I would love to do both the heads and the 750+ ci engine.....I just need someone willing to try it. Pretty much every customer wants a guarantee that there engine is going to run. That is why they are having a custom build engine in the first place. If they dump 10-15K for some heads and intake and it doesn't work, then who is going to pay to fix it? It's a tough call. I would still love to do it though. Hope this shed some light on it from an engine builders point of view. If anyone wants to builod an engine with them, by all means, let me know. I would love to be involved. I'm all about some cool new chit to play with.
Eddie

I don't want to start anything and I understand what is being said, but at one point a 598ci engine wasn't off the shelf.
Maybe if I hit the lotto.

You are absolutely correct. It doesn't seem that long ago that 598 was considered not only huge, but exotic. Now, it is commonplace. They account for about 80% of the engines that I build.
Eddie

No Gladhanding Here!
 

Sorry guys, I did not mean to offend anybody, its just that now your post count is up to three, keep it up the industry needs all the help and input it can get!
I just would like to know that people behind the scenes here are not trying to pump the post count for advertising or to sell the site again! This type of practice goes on in this forum industry a lot now and its all for the money obviously! not really for the bebefit of the forum users.

Secondly, I apologize if I sometimes seem to make what seems to be negative comments to some, but I just am somewhat intelligently opionated, but I will usually back my comments with fact and basis if the situation necessitates it!

As far as a small block "knocker" if you really know Raylar you will know that we developed and have been selling an all aluminum freshwater cooled, variable cam timed electronic fuel injected state of the art LSM550- 550HP for over two years now and were to market so early (boat show premier at LA Show in 2007, well before anyone else in the marine engine field ever even started talking about LS marine engines!! LS small block negative, not hardly we build and sell them, need one give us a call we have two in stock!!
What you will usually get from me and Raylar in my comments is , no bull****, no rumor mongering, pretty true facts, real accurate evaluations and expierenced backed opinions and information, assistance on engines and engine builds.
I make my living doing same and I pretty successful at it!
If this appears negative, I apologize, but I think I give way more than I get from my help and comments here on OSO!
I have built and raced more small blocks over the years than I can remember or count. their record and acomplishments speak for themselves over the years and today with the new LS platform the tradtion gets even stronger. They have their place, even in performance boating, thats why we build and market one, but in this application as stated by the threadstarter, I as well as most others who have good working knowledge and expierence, these heads and products need to be proven in marine endurance aplications and their costs for a top end of an big block, small block or LS platform engine with all necessary manifolds and hardware looks to be about three times the cost of high quality aftermarket head and manifold systems available that will generate the comparable horsepower and torque numbers with proven endurance and reliability!
I am always open to learning to ride new horses! But I 've got a personality like the great state of Missouri- "SHOW ME"!!!

To all OSO'ers here keep up the good and constructive input and threads, we all benefit and learn more every day!

Best Regards,
Ray @ Raylar

?
 

I would listen to Ray. I can assure you he knows what he is talking about and has the reputation to back every word he speaks. Regardless of post numbers and website sales.

Just my .02

Billy:drink:

Ray,

I am pretty familiar with your stuff and you and I have the up most respect for your knowledge. I read every one of your post in full because I want to know what you have to say. but lately I have just noticed they seem a little defensive about the SBC thing. My last boat was powered by 850hp SBC's and was a very successful project. the boat was a 2002 28 Daytona that went 149mph, pretty fast for those days. I have been researching and looking into building my next SBC project.

You didn't and will never offend me, nor does my old school father. I was just making a friendly observation.

BTW- Whipple has a off the shelf intake manifold that will fit these heads.

MP

My 2 cents about the 4 valve heads on NA engines, again from experience with diesels and gas many years ago so somewhat by today's electronic age.

None the less the principles of how an engines breathes have remained the same.

PS - I'm negative not Ray - LOL!

Now the 4 valves although able to breathe better at high RPM will not and I say that without hesitation work well at the lower RPM's needed to get a boat on plane with ease because the engine will not make good horsepower at those low RPM's.

Think about this, the best torque low rpm engines (NA's only) have very small valve area, this is because without good piston speed the cronologic time an intake valve is off it's seat is to long and the negative pressure in the cylinder will drop to almost nothing, can't suck in enough air in time.

The smaller valves offset that making a smaller hole that increases the air velocity and not volume so the suction time into the cylinder is longer. Don't forget there is a time period when the piston is going upward and the intake valve is still open, without velocity the piston pushes the air back out (to a certain point). Velocity allows the cylinder to keep filling.

With the 4 valves there is almost no air velocity at low speed, think of any import car with 4 valve heads - no ability to launch off the line even in drag racing without lots of RPM's.

Now take those same heads and put postive air pressure with them like a "blower" and you have a great power package for a boat.

Think diesel for a minute and all the advancements in postive air boost that have been made in the Dodge, Ford & Chevy to be able to build a higher Hp engine yet still have bottom-end pulling - variable turbos, multi turbos, variable timing, etc all things to compensate for the 4 valve heads having no air flow at the bottom end range.

I say this as having fought this for years, think about the load on a boat, everyone has some variation of semi or surface periecing props to go the speeds you go - the biggest problem is when the boat goes slow the prop is all wet - that is why for years the foreign engines don't make good boat engines. They can't over come the fact that their multivalve heads can't work well at low rpm's

Regarding your point #4, any documented endurance information you can share on your LSM-550?? I'm from Missouri...:kiss:

Some food for thought on the low speed tq and hp needed for boats: In the mid eighties to early nineties time frame Eagle Engines Limited built large displacement 32 valve engines, the following numbers are from their dyno runs. 705 inch N.A. on regular pump gas 958 hp @ 5,000 rpm 952 ft lbs tq @ 4500 rpm. 752 inch N.A. on racing gas 1200 hp @ 6500 rpm 1300 ft lbs tq @ 4500 rpm.
The 4 valve design is much more effective in filling the cylinder which translates directly into hp and tq. This allows the lower lift/shorter duration that Arao uses and relieves stress on the valve train which promotes longevity and reliability. This shorter duration prevents the piston from pushing the air back out before the valves close thus allowing increased power production over the 2 valve head lower in the rpm range. Case in point most diesel manufacturers are moving to 4 valve heads to enhance power production. Diesels are a low speed engine that respond well to this design. The main reason they are playing with the dual stage turbos is to try to eliminate low end lag and high speed air starvation at the same time.

I know big blocks and diesels are two different animals but I still think there is some common ground with 4 valve heads and low speed tq and hp production.

Again I am not trying to step on any one's toes I'm just trying to get a better understanding as to whether these heads would work for marine applications and increase performance and reliability at the same time.
The theory behind them and the info surrounding them would indicate so in my way of thinking but I've been wrong before.

Woody,

Truck diesels have used 4 valve heads commerically since the 70's (maybe earlier), I agree there are many meritts to 4 valve as you explained.

I want to look back in time diesel wise regarding N/A truck diesels such as the early Macks 2 valve heads, early Cummins 2 valve heads, hell look at the NA B & C series all 2 valve heads designed for low rpm torque in dozers and backhoes.

Let's look at the Lambos they race in offshore, they are 2 valve engines made for industrial equipment that had 4 valve heads out on for better breathing ast high rpms to get more HP but the tractors remained 2 valve, low rpm torque.

I want you to also think about something else, N/A gas engine compression ratio 9:1, N/A diesel is 16:1 and have seen higher. Even with that the 4 valves lacked bottom end.

Don't get me wrong, 4 valve heads far superior to two valves for overall HP. I just think in a boat as a N/A engine you will find that there is no torque there - BUT I've been wrong as well!

On there site it says 534 lbs of TQ at 3000 rpm. That seems to be a lot of TQ for a naturally aspirated 350ci @3k

MP

We have a nice easy fix for that low torque number at low speed!

But honestly, Ford's been doing this for years with the 4.6 and 5.4 motors, some are NA'd and others our SC'd. The NA's do quite well at low speed torque but they do best at high rpm.

Our manifold bolts right to these, so does our 2 different intercoolers, as well as our 3.3, 4.0, 4.5, 5.0 and 8.3 liter superchargers!

Thanks,
Dustin

Haven't they been making these heads for quite a few years .If not this company ,one with a similar name .Old brains forget

Coool!!!!!! I stopped by Russell's shop (ARAO Engineering) the other day and saw this. I asked him about marine applications and it hasn't been his target market. I hadn't seen him in over 25 years.....he's always doing something tricky!

Been discussed many times on LS1Tech.com. They had potential, but were very very expensive ($10K), had a proven competitor in ET Canted Valve heads and I don't think they ever came to fruition.

Dustin,
If you have developed manifolds that fit them does that mean you have had some "play" time with them? Please elaborate if you have. Do you have any dyno numbers for engines with these heads and your superchargers you could post from tests you have run?

I don't think they have ever tested these heads but the heads use the same pattern as the L92 heads, I think. So it is the same intake they use on other LS motors.

MP

They were called Dominion heads 10 years or so ago when I first saw these. A guy I know had them on his Vette way back.

It's still a good idea.

Weapon,
What size engine did he have in the vette? What was the low speed tq & hp like. Overall how did he like them?

406 cid He hasn't ever ran it on a dyno his guess is 700 hp.

I didn't think Jeff still had them but he has 3 extra heads other than what I knew of.

Love it!:ernaehrung004: So true......