Bobby: I am pretty familiar with the stock 4th gen PCM. The biggest issue with my mythical (or is "imaginary" a better word?) centrifugally SC 1000hp Dominion/Arao setup would be injector size. Biggest injectors you can use with the stock PCM are 50lb's. Not nearly big enough. You could LJ's low impedance injector driver "kludge" (I mean that admiringly, for sure). But trusting my $20,000+ motor to something of that sort would make me a little nervous. You might get away with 50lb injectors on an NA 4V setup, as they should be good for ~800hp.

Anyway, the stock PCM has other limitations. There's the 7,000rpm limit for one. This would be more of an issue with an NA setup, as with the way I like to setup blower cars you don't need to rev the snot out of them.

And there's the issue of spark current. You can't run high voltage through the Opti for very long (I have proved this twice), and considering that my dream motor would be a boosted and/or juiced 1000hp setup, you would need a hefty spark! So you would need to ditch the Opti, IMHO. And AFAIK that means a complete aftermarket system.

Not having fully thought this through, there are likely some other issues as well.

This is fun to think about, but again, I'm in awe of someone with the cojones to actually do it

Rich Krause

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

[This message has been edited by rskrause (edited May 03, 2002).]

 

FWIW I would stay away from haltech unless you are running a rotary engine - we have one on a 97 dakota and it (E6K) is the worst EFI I have worked with yet. Speed Pro/Fast with a wideband (or without) it 1000x easier ot tune and setup. The old Accel DFI is a breeze compared to the haltech.

And then there are the bugs - did I mention that the logging software crashes if I log more than 3 pages of data. There "MAY" be a fix for this, but I have to pay for a firmware update to find out - no guarauntees.

Chris

 

Curious Rich, do you run an FMU? Are 50lb injectors enough for 700 RWHP? Also, if you did have the Arao's you would have that much on motor. I think it would be a lot more drivable. My friends 650 RWHP Mustang is just ridiculous, even on monstrous 18s. Sounds just like your car, breaking the tires loose in 3rd and 4th. Anywho, I talked to Russ Arao for a while on getting a set of the heads for a Mustang, a friend and I were gonna build a 418 Stroker with Araos, and he figured we could expect around 700 RWHP. Not too bad, but when you consider all the extra $$ you have to spend to get there, its not feasible for us. It WILL have them someday tho. He was gonna give us an EXTREMELY good deal on a set of Yates style heads, but we would have to change direction after buying some parts to do that. Also, what kind of injectors are the stock LT1s? Peak/hold or saturated? I have not had any trouble doing a simple conversion with Honda ecus to change between them, but it seems the KLUDGE is a little more involved. I didn't keep up with it as well as I should have.

BIG SHOW - Do these heads fit ok in the confines of 4th gen? What about with Hooker headers? I will have a set of these heads one day, no question.

UB & Big show - I am willing to sacrifice my car so everyone can see how the Araos perform. All you have to do is send them to me! I know, it is very generous for me to do so, but I feel that everyone will benefit from me having a set of these. Especially me at the track!

 

Correct, the hookers will not fit. On their website www.araoengineering.com it lists what headers you must use (Stahl).

 

dead link

 

http://www.araoengineering.com/

------------------
Jeff C - Utah
1994 383 Z28 M6
Bored, Stroked, Splayed, and Sprayed!
www.nvmyz28.com
Utah F-body Assoc.

 

Wow, I first read about Arao 4 valve heads for F-bodies 10 years ago. Never thought I'd actually see or hear about anybody using them.

Re: Krause and transmission, would a Lenco be about the only manual that could handle the power of a 1000 HP setup? And how hard would it be to fabricate and install one in a 4th gen? I'm thinking somewhere between insanely difficult and next to impossible.

....and I thought spark plugs were a PITA on these cars. You guys are way over my head.

 

B: I am using a Carroll Superfueler and the stock FP regulator. The SF drives 3x92lb low impedance injectors. The stock PCM uses high impedance injectors and the injector drivers will overheat if you use low impedance pieces.

I still think that these heads are awesome but that unless you are somehow restricted from using forced induction or just want to be different they aren't a sensible choice. But OTOH what's "sensible" about a street car 600+rwhp anyway

Rich Krause

 

Its been a long time but it things are going good.....and it looks like I ll have time for cars again soon.....

I ran the Dominion heads that Bob has.....It was in a 93 formula about what 4 years ago? I started it on 58 lb injectors.....and it took only a couple days to figure out that they were not enough....so I put 72's in it....

It did take some alterations.....at the time it was a lot....looking back.....or considering what I know now....not that big of a deal.....

The heads are awesome....plain and simple...

1000 rwhp is not far fechted at all...keeping tread on the tires is the hard part..... I m one of the few peopl eto have run them....and I would do it again.....

 

GODDAMN people!! Quit slacking off and someone get these heads going.

 

Not quite Arao's, but interesting technology nontheless. www.coatesengines.com. Spherical valve heads. Anyone know someone that has these?

Eric Bazan

 

396jon, any more info you would care to tell us about your dominion powered motor? LT1 based, SBC, CID, etc. etc. Power? E.T.? I have been waiting forever to find someone that is or has actually cranked a car with these. Anything you would be willing to tell would be great. Feel free to make it a really LONG post.

 

Brian, The engine is now in the hands of Bob Gable but I did run it in a street car....It was/is (depending on what Bob has done) a 396 LT1 . It uses 5.8750 rods, a .900 base circle cam... I think it was 242 About 550 lift....Cant really remeber....I m sure Bob would have itr somewhere....

I made the headers....and built the engine....etc.....It had custom lenght pushrods.....(one of which exhuast I think , turned out to be a off the shelf lenght for a foed clevland or windsor or something.....)

The intake was a well ported LT4. The heads flowed somwhere around 360 cfm at 500....again I d bet Bob has this stuff written down somewhere...I ran it with an electromotive tec 2......and 72 lb injectors....The responced was incredible....light switch like.....It would /could easily do 50 mph burn outs in early tuning stages....

The ac box had minor grinding....the ac acess bracket had grinding and redrilling...., the canton pan would rest on the casting ridge on the rack inpinion if it wasn t ground down.....I did have ac/heater etc......To be honest I don t remeber a lot now.....in relation specifically to the heads....

The cam was a solid roller....the heads use forked rockers....bucket adjustable......so running valves took awhile.....the head bolts run directly through the intake so a plug goes in the roof of the port after the head is installed...I was never concerned about the irregular pushrod geometry after running the heads.....( alittle before) but they had no problems.....at all....it was just the fabrication to do it....being the first one and all......The heads are converted old style heads....basically plugin gthe water ports going to the old style iintake....

The heads are nice.....and flow incredible...esspecially at low lifts.....I had ported heads....with I think 1.45 intakes....thats two of them....again Bob has em now and he sure nows better then I at this point.....I would run them again ......but probably in a more user freindly chassis......

 

my daddy isnt that ugly! lol
j/k Bob

 

Hey its been a year... Any thoughts on theese heads?