TA

iTrader: (1)

Yes, multi valve heads are not new. Honda has been using 3 valve heads in their dirtbikes for about 15 years, and have done a LOT of development on them. Actually both Harley Davidson and Indian made board track race bikes in the late teens, early 20's that used 4 valve heads. None of this stuff is new, but the ability to test and refine these ideas, and the ability to cad-cam and CNC machine complex designs makes them dramatically better and more cost effective to produce. Will they be worth $3000? Probably not in max HP gain, but it should make a much better torque curve, they are designed to improve low and and mid range power. BG has proven to be capable of taking a good design and developing it to a much higher level, and producing an excellent product.

As for the original photo posted, it says they are still in development, so they will probably look substantially different when they make production. And for those internet know it alls, port flow numbers are a component of head performance, but do not necessarily make for a better head. It's really a marketing tool, and it's pretty common knowledge that AFR and many others use "optimistic" port flow numbers for advertising, and the magazine educated engine know-it-alls buy them left and right. There is a lot more to the performance potential of a cylinder head design than simple flow rates.

When we see dyno charts of the same engine, with BG 3 valve heads swapped onto the engine in place of another good head, like the vortecs or something, then we will know where we stand. At 3K, I'm interested, but not enough to be the Gunea Pig just yet.

Tech @ BG

Funstick,

Thank you for the offer, but we do all of our testing in our own facility. This allows us to monitor the data more specifically. Such as individual cylinder pressure, fuel flow, and lambda.

Grim Reaper

Thanks again Tech. I hear you with higher lifts not being necessary, especially with a multi-valve head. I do understand that there is a ratio between the valve size and how far a valve must open to obtain max flows. And thus two smaller valves only need to open a much smaller amount to start having significant flow - thus the flow of your head below .400" will be phenomenal (compared to a conventional single large intake valve head).

The only thing I hope BG considers is that most of that Hydraulic Roller Cams (which 87 and later engines use) have lift in excess of .500" (with 1.5 RRs) when the duration on the intake side exceeds 218. Of course, since you are including rockers, you could use a smaller ratio. (I'm just trying avoid buying a custom hyrdraulic roller cam that will give me the duration I seek but have the lift cut down).

As for your target price range, I'm in. BTW, what port sizes are you guys considering?

Tech @ BG

As for your target price range, I'm in. BTW, what port sizes are you guys considering? [/B][/QUOTE]


Glen,

Thanks for the feed back... As far as port size, I'm not sure where we'll wind up, we're playing with different sizes right now.

fb305svs

sounds pretty sweet....

ploegi

Multi-valve heads have been in use in *cough* japanese *cough* motorcycles for decades. Then they started showing up in their auto engines. It seems to have taken the american manufacturers quite a while to realize the potential benefits of multi-valve systems, and in the late 80's, they started showing up in american cars. Nowdays, they are fairly common, though the japanese/italians still do it best.

The ZR-1 motor in the corvette was a very pretty peice, but, GM could have (should have?) gotten a LOT more power out of it without very much trouble at all, and still stayed within emissions parameters. Not sure why they didn't. It would have made a very nice performance peice, had they expanded production, and used it in more vehicles, rather than keeping it a corvette specific motor. (dealer cost for a long block ran about 27,000 back in '92, good luck finding one now, and don't even think about any aftermarket parts for it.......)

In any event, two small valves will outflow one large valve every time. Along with the other benefits associated with multi-valve systems. For not a lot more money than a good set of complete heads, this looks like a viable option. I am looking forward to seeing tests done, and published.

I am also quite pleased that a rep from the company took the time to comment/educate us here on the forum, and was not scared/chased away by some of our more skeptical members.


Cool, I look forward to further developements.

funstick

Well as im assured that you do infact do such a thing. it would be nice to get some third party input( id also like to see how they perform) in comparision to some of the best 23* heads that ive seen. i do have a 400cube dyno mule id be willing to run testing on.

Tech @ BG

Funstick,

Again, we appreciate your offer, but any of the outside testing we do is done through laboratory facilities that specialize in statistical analysis.

MrDude_1

how about i do some real world testing...

understandably, you want to retain control over it... so you guys can build me a 1stgen camaro with it, and i'll just put the miles on it for ya.
:lala:



lol anyhoo i was talking to a friend about this... what kind of springs will this use? somthing thats already in the aftermarket parts bins under a diffrent motor? modern oval/beehive springs?
you kept mentioning valve weight.. what kind of valves are they? Ti retainers and locks? if the user wanted more lift anyway, how much could this head support?

funstick

Well are they avaiable yet ???. id be glad to buy a set. i have a set of the 4v arao enginerring heads that ive yet to play with a set of mr2 ported 23* brodix track-1 that flow 330cfm and another set of dart eagle 230cc pro head that have been cnc ported and yet another set of world products 230cc heads that were ported. i was going to run them on a 400ci dyno mule keep the camshaft the same retune the AFR and timming curves for best power and post a report on the net. as to what the best power per $ would be.


I was thinking the bg heads might win.

Tech @ BG

We're still in the testing stages on our cylinder heads. We hoping to have them released to the public towards the end of the summer or fall of this year. Once we get closer to release we'll have some more specific information available.

pasky

Quote:

Glen,

Thanks for the feed back... As far as port size, I'm not sure where we'll wind up, we're playing with different sizes right now.

Any plans to design 3 valve heads for a GEN II LT1 and have some reverse cooling passages made with these so they are direct bolt on?

Tech @ BG

Not at this point, we need to see how the production units perform, and sell before we decide completely where to go next.

pasky

Understandable. I suggest you check out camaroz28.com also and post your product in the advanced tech section. Im sure you will draw a crowd and have a lot of very interested buyers. Theres is still a very large market within the GEN II SBC community. Thanks for the reply, i'll be keeping an eye out.

MrDude_1

Tech @ BG

Can't answer that at this point since we're still in the developmental stages. Onces we get closer to release we'll have more specific information available.

MrDude_1

ok, but as user feedback, id STRONGLY encourage you to design it in such a way that .600 lift is easily obtained... with the ability to go higher with machine work

pasky

I agree with Mr. Dude. Not a lot of people are going to go with a $3000 product and want to have stock or intermediate lift ranges being the only attainable lift without having to spend more money on machine work to achieve the lift they desire.

Tech @ BG

We can't answer that until we determine how they are working. Multi valve heads generally use less lift than a 2 valve setup would.

funstick

well id like to chime in on a the 3 valve facet of this again. the flow % of 75 to the intake is not entirely accurate IMO. first of all the exhuast gas leaving is a much more easily manipuated fluid. hot gass's flow better. just like hot engine oil. secondly the exhuast ouput in reality only needs to be about 60% of intake and you can make very good power without realy screwy dual pattern cams.

also the other thing to keep in mind is flow. ive got a honda head from a 89 accord weve been working on for about a yr and the intake flows 220 cfm at 500lift with 2 small .875 inch intake valve and the single 1.10 exhuast flows 180cfm at .500 lift. now this is with a production head and some decent porting. comming from the aftermarket i would assume the ports shapes would be worked to properly produce the appropriate flow amounts.

also i have seen good 23* sbc head on a 1406 exhuast gasket flow in the 255cfm range. so im not even remotely concerend. the improvemnt in low flow velocity and cylinder filling with the multi valve arrangement will net good increases in power without need to run high lift values over 550 660

tilstad

On the cars I've had with 4 valve heads, the peak performance went right up, but lost alot of torque down low. THis is how I've always seen it, 16 valve four banger=no lowend. 8 valve, same engine, lotsa torque!!

Do I misunderstand the BG representative here, or is he saying their heads will perform the opposite of all other multivalve engines?

Grim Reaper

A lot of the torque situation has to deal with the choice of cam too. That, and there are FEW multi-valve V8 cars. If you go to Arao's site, their head promotes a LOT of low end TQ when matched with a relatively mild cam. DeskTop Dyno also confirms this.

A more comparable engine would be the LT-5 from the early 90s Vette. They neither lack TQ or HP, especially when tuned and built.

88IROCs

Jus' a lil history,...

At the turn of the last century, GP racing was dominated by French manufacturer's. Hard to believe automotive technological development was once driven by the quiche-eaters, but we owe such groundbreaking developments as front-mounted engines -and later driveshafts- to them. However, the Italians were determined to end French dominance, and in 1907 FIAT introduced the 130HP race car. This car featured a 16,286cc(!!!) FOUR-cylinder engine which produced an amazing 130 horsepower at 1600 rpm (hey when each piston weighs 10+ lbs, revving the snot out of it is not an option), and had a cylider block that weighed 2000 lbs(!!!!!). It is believed that this engine's dimensions inspired Italian engineer Alfonso di Rigatoni to utter the immortal phrase, "Hey, theres'a no replaysamenta for displaysamenta!". The 130HP was a successful design, and the Italians dominated GP racing until the French cheated by changing the rules.

In 1912, Renault introduced the first four-valve per cylinder design for a racecar, and were quite successful until the Italian concern ALFA changed the rules by licensing engine-designs from Renault and installing them in lightweight chassis'.

So much for the idea that multi-valve (ie., more than 2) designs are new-fangled or were originated by the Japanese. Come to think of it: it kinds of puts to rest the notion that huge displacement is a uniquely American concept ( 800 cid of Sonny Leonard big-block ain't got nothing on 994 cubes worth of French 4-banger. Well, o.k. Sonny's got a slight 2000 hp advantage).

Next week: Auto Union (AUDI) hires out-of-work engineer, Ferdinand Porsche, to design new GP engines. Porsche deems the results unsatisfactory, as the engine tends to cause wheelspin at 150 mph. A.U. management responds by ordering that engine displacement be increased from 4.4 to 6.0 liters, and that braver drivers be hired.

Dewey316

Actualy, watching the history, and interminglings of the German Auto Industry in the early days is rather interesting.

ploegi

The ZR-1 motor used oil pressure to activate that second set of valves at higher RPM. (i.e. not being used at lower RPM) This is why it had good low rpm grunt.

While multivalve heads have been around for quite some time, I do beleive it IS the Japanese that first used them in a mass produced engine. (so far as I know......)

Dewey316

Define mass produced

88IROCs

I was thinking the same thing. Duesenberg introduced 4-valve heads on their 1929 engine. Unfortunately, two little ditties named "Great Depression" and "World War II" prevented them becoming widely accepted (i.e.,... too expensive). If I'm not mistaken, the same tunes doomed Cord's front-wheel drive models in the thirties.

FWIW, I believe Miller won the Indianopolis 500 a couple of times with a front-wheel drive racecar during the thirties. Quite a few years before anyone had heard of Honda, Toyota, etc.,... So American manufacturers had produced both 4V and fwd cars about 40 years before the first Civic arrived here -which was widely lauded for it's innovation (even the CVCC engine design was "borrowed", Mercedes had been playing with the idea since the '50s).

Dewey316

Not to mention, Aston has used DOHC engines, with multiple valves for years, many of Zee German makers have also. Audi ran turbo DOHC 4valve per cyl, turbocharged, cars since the late 70's. I guess if we are talking the volume of the civic, then maybe they were the first, but I would not consider Audi, Merc, BMW, or Ferrari (hmm, ferrari had the twin-cam motors in the 60's.) Small time manufactures, grated you don't see nearly as many ferrari's, as civics.

Grim Reaper

Okay, forgot about the LT-5s dual mode of operating.

Well, I will give another example. I recently bought my wife a Mazda 3 with the 160 HP 2.3 4-valve engine. YES, I know it's variable valve timing BUT that confirms my comment that it depends on "camshafts" being the key factor.

I can tell you this, that Mazda 2.3 has FAR more low end TQ than any 2.5 Iron Duke I ever drove. And they had the "torquie" 2 valve head (NOT). And, when the "variable valve timing" kicks in, does it ever scream in the top end for a little 4 banger.

It's more powerful on the top-end than the Ford Taurus V6 car I get from my work.

Grim Reaper

Another better example of "two valve vs multi-valve" is two motorcycles I owned. One was a late 70s Honda 750 Four with a SOHC 2 valve head. The other was a 1985 Yamaha 750 Maxim X with a 5 valve head (3 intakes and 2 exhaust). Other than the valve configuration, there was no other meaningful technological differences between the two engines. Both carb'd, both electronic ignition, no variable valve timing, single spark plugs, stock exhaust, etc.

The Yamaha was only a few years newer than the Honda, but the Yamaha had more bottom end TQ than the Honda - NOT a TON but it definitely was very mild mannered on the bottom end. Where the Yamaha REALLY shined was on the top end. It had easily 50% more power than the Honda. The Honda was probably a high 13s/low 14s while the Yamaha was high 11s.

The Maxim X was the same engine as the later Yamaha YZR 750 but with milder cams and more of a street/cruiser type bike as opposed to a "crotch rocket".

BruceEmbry

Hi BG Tech,
I have a GEN 1 350 with TPI intake. How will these 3 valves heads perform on this setup.
thanks!

305q_ta86

iTrader: (1)

I say they give us each a set for like beta testing..

Grim Reaper

Poorly and a waste of money. I figure it would be similar to a person having an asthma attack trying to breathe through a straw.

Tech @ BG

Since we're still in the developemental stages on these heads at this point we can say specifically how they would work on your application. Once we get through some more of our developemental testing, and we're closer to release we'll publish the information.

BILLET RACING

[quote=Grim Reaper;2147483]I would suspect that they would flow very well. I doubt they would be as good as the 4 valve/semi-hemi Arao Engineering heads with the spark plug located in the center of the head like a Hemi.

The valve clearance issue is a very good point as well as "valve train geometry" would be critical.

But for all the cost of these "exotic heads", why not just look at 18* heads?[/quote]


In a word forget it. We ordered 32valve Ford Cleveland cyl heads from him on 2/1/06. Paid in FULL USD$11k + to expedite the order with a promised delivery date of 90days MFG. and so far we received some pictures and a whole lot of bullshit promises.

Unless you feel like throwing your $$$ down the toilet, don’t even go there, take it from our VERY bad and costly experience with Arao.

I can write you pages and pages regarding this order with Arao, but I will spare you the headache.

Short Story...On Saturday, January 21, 2006 6:26 PM I Kevin Gall made contact via email with a company located in California U.S.A. As you know the company is ARAO Engineering Inc. the owner is Russell ARAO . In my contact email to ARAO i enquired about a special order set of FORD Aluminum racing cylinder heads - a product ARAO advertises & manufactures. After receiving a reply and several emails i decided to place an order with ARAO The product is special order Automotive cylinder heads to suit a Ford V8 for racing use at a fax quoted cost of USD $11,000.00 manufacturing leadtime ARAO states on paper 90days for special orders.

On 31st January 2006 payment via Int'l Bank Wire of USD $5,500.00 & 6th February 2006 USD $5,500.00 was completed in FULL to ARAO Engineering Inc. Bank account. After several more emails to finalize details and special requests i was informed by ARAO were engaged and going. After some waiting i emailed ARAO on Friday, June 02, 2006 12:39 AM to ask if everything was on track, i received a response back from ARAO that everything was fine and on track.

Again after more waiting On Friday, September 15, 2006 03:05:42 i asked via email a good friend of mine that owns a reputable drag racing supplies shop located in Whittier, CA U.S.A. to contact ARAO by telephone. He spoke with Russell ARAO and he stated to he was waiting on parts from an outside supplier - hence the delay. In months to come i have made ALOT of repeated attempts in writing, faxes, calls, emails to receive a date for finalizing and completion of my special order. I still have not received a date at which my order will be finished.

As of today Sunday, Jan 17th, 2008 nearly two(2) years later i have not received my order from ARAO Engineering Inc, only BU**SHT PROMISES AND ABSOLUTE LIES. The only thing i have received is pictures of my heads un-finished. I believe i have been patient and understanding and more than reasonable considering that ARAO has not delivered as promised 90days to manufacture.

From my personal dealings I heavily caution anybody wishing to part with their money to purchase from a disreputable company like ARAO Engineering Inc. If you have any questions/comments please email anytime! ....Arao Engineering has been reported by myself to the L.A Better Business Bureau & also C.A dept of Justice ,The office of the Attorney General C.A., Recently today 17th Jan 2008 also reported to Federal Trade Commision - Offices & Bereaus. **It is noted Russ Arao Failed to respond to any complaint(s).

383backinblack

they didnt have any problems shipping out thousands of poorly assembled, defective carburetors for years

FireDemonSiC

Hey I hate to go grave digging on TGO but is there any further word on these heads?

1989GTATransAm

iTrader: (3)

They appear to be DOA.

gregsz-28

iTrader: (1)

I may be misunderstanding what he's saying, but won't an engine rev just as quick, no matter what the spring pressure is?
It should be irrelevant what the spring rate is, since for each spring that is being forced to compress, it is being countered by another spring trying to decompress?

Apeiron

Some of the engine's energy has to be used to open the valves against the springs.

Not really.

RED_DRAGON_85

in a frictionless world, yes.
in the real world, no.

if it takes 200 lbs to keep a big valve under control, and 100 lbs to keep each of two small valves under control, the small valve setup will take less power to turn.