Arao 4-Valve Heads

[MonteSS427]

I found these in someones signature...and I'm glad I did!

I finished up my engine build in DD2000 with the head flow numbers for the C2 heads...with phenomenal results! I gained 200HP over fully ported aluminum aftermarket heads! It put it over the 1000 mark....and this is a small block!

Anyone else have any experiences with these?

[Mikael]

If i recall correctly, two people own them, neither has run them.

[Vince]

Go Bobby Go!!

The "Big Show" will get them to run. I have faith

Vince

[RedIrocZ-28]

I keep hearing about these 32 Valve heads but NO ONE uses them... EVEN if they own them. I know the fabrication is insane to get them to work but for real! Someone run them, please

Would they work on an L98 block or not?

[kevkop94TA]

I read in another post that Big Show himself said he only needs another month or so. I don't know how he can handle it, cause the suspense is killing ME.

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1994 Trans am GT
Borla cat back, 3:73's, Moroso CAI, 1LE bellows, 160* Stat
SLP Ram air hood, LT4 KM, Chrome Firehawk Rims. BFG DR's
Race Trans built by LevelTen, 2600 LevelTen Torque Converter, Hotchkis STB, Edelbrock PHR
E.T. 13.681@98.87 1.90 60'

I want to start a new life, Get myself a sharp knife, Look into my own life, Kill things I don't like in me
-Ill Nino

[Shon Herron]

The BIG SHOW is working on it, I am sure he will take donations to help out. I beleive his cam and pistons are at least ordered, they might be in hand now.

I will direct him here to see if he wants to post.

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94 Z28 A4(3.73)LT4H/I/HOT cam
BMR/Spohn Suspension
Yank 9ST3500
1.699,12.27@108/RW3395
stock fuel tables

[The Big Show]

*laughing*

Believe me, one of the main reasons I made such an effort to get these heads was the fact that I knew if anybody could finally put the myths to 'rest' it could be me. Mainly because of my setup and my desire to always want to do something different. My car is pure race and doesn't need any of the 'creature comforts' people want in a street car so I knew whatever needed to be done to get these heads to work could be done on my ride. Turns out there really isn't anything that needs to be "done" so to speak...

At this point, the pistons are on the way (took over 6 weeks from JE) as well as the cam and my big dominator to feed these monsters. I'll be back to fuel injection in a few years but for now I need simplicity so I'm running a carb.

All questions are welcomed. As you can see from my site I don't really hide anything unless I have been told specifically not to divulge info...

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Bobby Simpson II *Bling Bling* Sold Seperately...
32 Valve Dominion Headed 1994 Z28... "White Lightning"
Budget Performance Racing...Layin' the smack down

"Ain't no future in frontin'..." <---This You?

[MonteSS427]

Actually Arao says these are a direct bolt on deal. ?

[rskrause]

<font face="Verdana, Arial" size="2">Originally posted by MonteSS427:
Actually Arao says these are a direct bolt on deal. ?</font>

I looked into these. A very liberal definition of "bolt on" for sure. In theory, you might actually be able to install these without removing the motor, though not on a 4th gen. There is some block machining needed for pushrod clearance, but I suppose it could be done on the car as could the cam swap, etc. that is needed. Most people wouldn't consider that a "bolt-on". Heck, installing a new bottom end is just a matter of bolts and a little machining too.

What scared me off more than anything was that in additon to the heads and everything to go along with them I would have also needed a new engine mangement system to run FI (I have no desire to go back to a carb on a street car). This would raise the parts cost alone to the $10K range and then the thing would have to be tuned.

The result would have been less power than I have now, unless I kept the blower. With the blower, I really think it would be too much power (never thought I'd say there was such a thing) for a street car in two respects. First and most obvious is traction. Since I can break street tires loose in 4th gear at 85mph now, what would another 200hp or so do? Second, I like to shift. And AFAIK there isn't a street transmission available that will handle that much power. Same issues with the rear, what posi could I use? I sure don't want a street car with a spool.

These heads seem totally awesome, but except for a race car do not make sense to me. You can make as much power much more easily and cheaply with a blower. And as I opined above, a power adder plus these heads would really not be practical on a street car. I suppose you could do a nitrous setup and run NA on the street? Hmmm.....

My hats off to the folks the desire to do something this wild, but it really isn't for most of us.

Rich Krause

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'95 Z-28 383 with Vortech, nitrous, etc.
"1FASTZ28"

[This message has been edited by rskrause (edited May 02, 2002).]

[MonteSS427]

You don't need a cam swap to run these heads. Although you can get a custom cam ground to better match the power characteristics of these heads, it is not necessary. They still use standard style cams. The valves are operated by special rockers.

Other than that, I agree with you Rich. These heads have truly insane power potential...mainly because of the fact that unlike conventional heads that hit a power peak and then drop off.....these heads just keep on going, and going, and that power curve becomes a line aiming straight for the sky, without stealing from the low end. Though I do think that a 1000HP blown setup with these heads (i know, you can get much more than 1000 out of it....but keeping it limited here) can be driveable on the street. Especially with a good fuel injection setup and a centrifugal style blower like Vortech.

[unstable bob]

Yeah, yeah, yeah....Give Simpson all the limelight. I can't believe unstable bob's name isn't mentioned ANYWHERE in this thread! Just remember, punks....WHO'S YER DADDY??????

http://members.aol.com/Fredrick518/Photos/DominBob.jpg

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"unstable bob" gable, JAT, MON.

AMERICAN ROAD WARRIOR!

WEAPON OF CHOICE:
1979 Black WS6 Trans Am
Engine: Oldsmobile 455, bored .030 {462 CI}
Induction: Performer Intake. Demon 750 Carb
Exhaust: Hooker 1 7/8 Headers, unstable engineering 3 in exhaust w/ X pipe. Power Effects mufflers.
Cam: Comp Cams 280H
Transmission: Fat Buddy Racing TH400 full manual valvebody and trans brake, TCI 2500 stall converter.
Rearend: GM 10 Bolt, Eaton Posi unit, 3.42 gears
Front Suspension: VB Composite Monoleaf set up, Tubular upper and lower control arms, Carrera adjustable shocks.
Rear suspension: VB Composite leaf springs. Carrera Shocks.
Wheels And Tires: F: Compromotive 17 X 9 w/ 255.45.17 BFG Comp TAs
R: Compromotive 17 X 11 w/ 315.35.17 BFG Comp TAs

NJ Plate: BF HAMR

396 CI LT1 w/ Dominion 32V heads still in the works.

[rskrause]

<font face="Verdana, Arial" size="2">Originally posted by MonteSS427:
You don't need a cam swap to run these heads. Although you can get a custom cam ground to better match the power characteristics of these heads, it is not necessary. They still use standard style cams. The valves are operated by special rockers.

Other than that, I agree with you Rich. These heads have truly insane power potential...mainly because of the fact that unlike conventional heads that hit a power peak and then drop off.....these heads just keep on going, and going, and that power curve becomes a line aiming straight for the sky, without stealing from the low end. Though I do think that a 1000HP blown setup with these heads (i know, you can get much more than 1000 out of it....but keeping it limited here) can be driveable on the street. Especially with a good fuel injection setup and a centrifugal style blower like Vortech.</font>

Good point about the cam, but I think it'd be silly to spend $5K on heads and another $5K or so on "ancillaries" and then skimp on a cam!

I know an engine with these heads and a centrifugal SC or turbo could be made perfectly "drivable", but would the car be? Like I said, if 700hp breaks the rear loose at 85mph what would 1000hp do? I can't figure out what tranmission could be used (no automatics for me, please) and what rear end? I guess a better word than "drivable" would be "usable".

Believe me, I am not being critical and I hope it isn't a case of sour grapes. I admire people like "Unstable Bob" and Bobby Simpson who are willing to try this stuff out and share the experience they gain with us mortals. I guess I'm just thinking out loud and convincing myself that I made the right choice when I decided against these heads. Maybe I'm a little jealous?

Rich Krause

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'95 Z-28 383 with Vortech, nitrous, etc.
"1FASTZ28"

[80ci-to-350ci]

Yeah, I've been thinking about this lately. I just got done talking to a V8 friend of mine about this. I imagine that these heads simply allow the airflow to maintain higher velocity throughout a larger power band. Torque peak is flatter, and it allows you to rev more.

The big show, do yourself a favor and go back to EFI someday, you won't regret it. When you work with RX-7s you get used to the idea of ripping out the entire wiring harness, and buying a full stand-alone ECU. The stock ECUs just can't cut it. 2nd gen's used MAFs that were way too small (and there is no upgrade alternative), and maps suck (ie. rich and lean spots throughout the rev range, and stock timing maps will KILL a motor because when you advance port timing, you need to retard proportianlly).

There are many benefits to a properly tuned EFI setup, and the only downfall being cost. I know a place in AUS that will sell a brand new Haltech E6K w/ flying loom for $780 shipped to the U.S. in 4-6 days. Another $120 for GM sensors (most RX-7s use these too ), and you're set.

This way you benefit from complete control over the engine's behavior throughout the entire rev range. Say you get a large cam that decreases low-end driveability. Advance the timing at that portion of the map until A. torque begins to drop, or B. You begin to register knock. Advancing the timing in lower rev ranges does a huge amount to increase chamber velocity (ie. torque). With that you gain much low-end response. Doing this throughout the rev range you get a much SMOOTER/HAPPIER engine. Torque curve will be flatter, and peak torque will be raise TREMENDOUSLY. Right around torque peak is where you tend to retard a bit, but once air speed drops (ie. past torque peak) you can begin to advance it again.

Of course then there is fuel. A good head design will allow you to run higher CR on pump gas, due to swirl (increased mixture distribution). Tuning an entire fuel curve allows you to run leaner ie. create high chamber velocity throughout the useable powerband. It also improves gas mileage and driveability at cruising, low load situations, as you are able to lean the mixture considerably (which, is also being more thoroughly burned because of timing advance ).

Anyways, if you already knew all this, sorry to take up space. Just giving a suggestion. If you need some advice on EFI setups, let me know

-Brian

[This message has been edited by 80ci-to-350ci (edited May 03, 2002).]

[RedIrocZ-28]

Actually Brian, I think we could use your brain over at thirdgen.org's DIY Prom tuning board. Just let us use your brain..come on..let us use it I learned more from your post than I have reading for hours on that board.

[The Big Show]

*laughing out loud@my boy UB*

As far as we know, Unstable Bob and I are the Dominion brothers of the web so we must represent the brothahood well

Man, so much fun talking about the dom's but I know you are ALL ready for some action. Bob you hearing this? Let's get to it bro...

Rich, I totally understand all your points man. But as you know, the centrifugal blowers make their boost linearly so the same traction problems you have now, wouldn't be any different with the dom's. BUT (big but) you would have some serious benchracing bragging rights on the dyno I think for nominal use the T56 is more than capable of handling the power output but to go and beat on it at the strip has long since been proven by LJ not to be a winner. And your right about the cam, you will definitely want a custom ground cam after you see the flow numbers. I had a cam picked out and after I flowed the heads we had to end up calling Lunati and having them custom ground one cause we were COMPLETLEY off.

To call these heads a bolt on is like saying you could bolt on an engine rebuild in your driveway. Doable, but not exactly feasable. I think Rich covered all the aspects necessary as far as the block machine for the pushrods but why the need for an aftermarket computer?

Brian, your pretty new so you haven't gotten a chance to follow my legacy here for the past couple of years. It's been nothing but heartache man and last year I almost gave up and sold all this stuff. I had Vortech supercharged 383 w/speedpro and on board laptap, blah blah blah...After my "mishap" I decided to ditch all the fuel injection and go back to simplicity. I might have to hook up with you on that Haltech though for that price. Geeze

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Bobby Simpson II *Bling Bling* Sold Seperately...
32 Valve Dominion Headed 1994 Z28... "White Lightning"
Budget Performance Racing...Layin' the smack down

"Ain't no future in frontin'..." &lt;---This You?