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-   -   2-circuit, or 3-circuit Gen-3 Ultra Dominator? (https://www.racingjunk.com/forums/showthread.php?t=34037)

TheEngineer 12-03-2013 08:49 AM

2-circuit, or 3-circuit Gen-3 Ultra Dominator?
 
I'm planning on getting one of the new Gen-3 Ultra Dominators (1050 CFM) for my 427 CI, SBC drag race engine which makes about 660 HP at the crank. And, I'm not sure if I should go with the 2-circuit, or the 3-circuit version. Sometimes I foot-brake the car leaving at 2500 RPM in No-E and in Super Comp I leave on the Trans-brake at 4000+ RPM. So, what does everyone think; 2-circuit, or 3-circuit for my application?

curtisreed 12-03-2013 02:45 PM

Warren,

Go over here and join. Lots of good info on carbs.

http://racingfuelsystems.myfunforum.org/index.php

roadkill2 12-03-2013 03:08 PM

Pro systems SV-1 . . Solves all the problems Holleys have . . Very simple. Two carbs, one on each end, literally, with one big hole in the middle . .

It's Magic, it very seldom needs a jet change (if ever) and it does it's job every time . . No misses . . It doesn't care about air or weather. Never seen anything as simple and works so damned good!

Buy it new, from Pro systems and let them set it up for your engine. You won't be sorry . .

TheEngineer 12-04-2013 04:06 AM


Originally Posted by curtisreed
Warren,

Go over here and join. Lots of good info on carbs.

http://racingfuelsystems.myfunforum.org/index.php

Thanks Curtis, I've already signed up!

jmarksdragster 12-05-2013 06:43 AM

A 2 circuit is what I suggest, and I have a few out there running in the Super classes. They run well on the stop, yours makes about what my 23 degree 427 makes. Either the Quick Fuel or Holley will work, either may need fine tuning to suit your engine. You are signed up, check the for sale section out as well...

roadkill2 12-05-2013 10:22 AM

One more time on the SV-1 . .

We've had it on top of three different size engines, 6 camshafts and raced at altitudes from 3800 feet to 6200 and never touched it on Gasoline. This last season we sent it back and had it converted to alcohol and the only "Tuning" it needed to run a "9 Teen" was fattening up the idle air jet . .

It literally takes the carburetor (and the guess work) out of the tuning picture . .

And we've used it with and without the Biondo SLE, so it doesn't care how you leave the line, or what you do once you have . .

jmarksdragster 12-05-2013 10:40 AM

I've seen the other side, two different ones on a dirt track engine on an inertia dyno and it wasn't pretty. One local runs one, tells some it's great and tells others he can't get it right...

hammertime 12-08-2013 03:29 AM

I've ran the new 3 circuit one, it was decent. Still no where near as good as the APD 3 circuit.

I've sv1's very few have great luck with them. The tend to stumble a lot around here. Just from observation, how do you control the fuel splatter going WOT from the squirters, it splatters all over. Not being a smart a$$ just wondering if anyone else has seen this ?

oldandtired 12-08-2013 05:59 AM


Originally Posted by hammertime
I've sv1's very few have great luck with them. The tend to stumble a lot around here. Just from observation, how do you control the fuel splatter going WOT from the squirters, it splatters all over. Not being a smart a$$ just wondering if anyone else has seen this ?

Is'nt that the issue when the Preditor carb came out?

roadkill2 12-08-2013 08:18 AM

Never seen a problem with that. It does seem kind of like old fashioned shower heads, but in our case it all goes down that big old hole . .

We've run the same SV-1 on a 468, a 498 and a 582, on Gas (VP-116), and had two different cams in both the 468, and the 498, along with the current 582, and we've never had to make an adjustment from the original setup the carb came with. The thing is so simple there ought to be a law against it, and if you have any "Holley Smarts" at all, diagnostics are easy. The biggest problem, going back to the "Holley Smarts" is, you have to be careful with the SV-1 or you'll overthink the problem.

Let me add, we haven't had to touch the Jetting, no matter the altitude or air density, or the fuel. The engine demands and the carb provides . .

We sent it back to Pro systems when we made the change to Methanol and they "opened it up" for alcohol, and sent it back with a new Fuel Regulator that works in conjunction with the engine vacuum, so that when vacuum drops the fuel pressure goes up, keeping the float bowls full . . Works like Magic, but you have to adjust the regulator a tad when air density (Thus air pressure) changes. That's kind of "Round by Round tuning" but it's the only thing we really have to watch.

I'll add that we do have all the bells and whistles, EGT monitor (#1 & #8 ), and a run recorder for pass by pass data, so we're pretty aware of how well the engine is working . .

The only problem we've had with it was, when we got it back from the Alky Overhaul, we discovered the car wouldn't idle worth a [email protected] once it was warmed up, and wanted to stall when staging . . We were at the track, and overthought the problem . . Fussed with it until about 9:45 pm MDT . . called Tech Support and left a message, and within ten minutes, the CEO called us back (Midnight in Florida) and listened to our description of the problem, told use to fatten up the Idle Bleed Jets on the front system and told us to call him back if that didn't work . . It did and we've had no other problems.

As far as I know, in all the years of racing, I've never been able to call somebody that sold me any kind of speed equipment, on a Saturday night at 10 o'clock and got anything more than a hate call on Monday morning. Of course, for the most of that time I didn't have a phone in my pocket either!

Nonetheless, that's really service! I don't think Barry Grant would pick up the phone if I bought a system from him and had problems with it. Not that he's a bad guy or anything, it's just that most companies don't offer tech support to a racer on the weekends . . And those that do, most often don't offer contact with the Designer and CEO . . .

Now, let me qualify everything I know about Carburetors and Drag Racing. Not much. Most of my life has been spent fussing with Hilborn and (mostly) Enderle Fuel Injection. Always thought a carburetor was the Oddity on top of the tow truck's engine . . But, For many years I've listened to those who use Carburetors and learned one thing if nothing else.

"A Used Holley Carburetor is somebody else's mistake that they can't fix, so they sold it to you!"

95% of the time!

And I'd bet that goes pretty much for any other Carb off a race car . .


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