Dominator on 572 street/strip engine

[hemicharger572]

11:1 572 with a 283/283 cam. Works great with a 4k stall.

Hi,
the black Holley pumps 140 gph free flow at 14 psi. Only 120gph at 9 psi.
What pump are you using? And what set up are you driving?
My problem sounds simular to yours that you have had.
I didnt check the fule filters, I will do this too.

First I start with the bigger carb, the 1050 dominator, because its already here.
If it do not work, then I will try another fuel pump.

I am using the following regulator.
http://www.aeromotiveinc.com/product/a2000-bypass-regulator/
In the discription it says that a real big pump is highly recommended. Now, I am not sure if they just want to sell their stuff, or if it is the truth. any comments/ideas about that?

I think, or better my feeling says that the black holley is maybe not strong enough. Dont no..

 

[Bigal75]

I'm using a Mallory 250(MSD) Pump. Is it possible I've seen your car on YouTube?

Trust me, I chased my tail on this issue for over a year. I ran a Mallory 140 and it could not keep up. I noticed right away once I switched pumps.

 

[Hemirunner]

I'm Sure it wasn't on a 600" engine either and there wasn't a full exhaust after it. What you stated defies physics. I personally learned this lesson in the 80's with a hot 440 that we were trying to get to run well through exhaust manifolds. It would go to about 5100 and just lay there. We dropped the exhaust and it went 6500 like it was on nitrous.
I then had a full 3" exhaust on my 572 hemi with some fairly restrictive turbo mufflers. We disconnected them at the headers abd tied them up. Went nearly .4 quicker that night.
Assuming you have the cutouts before that 2-1/2" tube, you're probably good. Otherwise, that small tube is acting like a choke. A dented primary tube is one thing, a choke on the whole exhaust is quite another.

 

[Bigal75]

I have 3.5 inch Xr1s clamped to the collectors so no real exhaust lol.

 

[hemicharger572]

I'm using a Mallory 250(MSD) Pump. Is it possible I've seen your car on YouTube?

Trust me, I chased my tail on this issue for over a year. I ran a Mallory 140 and it could not keep up. I noticed right away once I switched pumps.

Yes there are some videos on youtube, two articles in online magazines (guess it was bangshift and the other one I forgot)
Alright, I keep that in mind.. Maybe I buy a bigger pump right away. Its a never ending story

 

[Bigal75]

...no, it never ends...

 

[hemicharger572]

I'm Sure it wasn't on a 600" engine either and there wasn't a full exhaust after it. What you stated defies physics. I personally learned this lesson in the 80's with a hot 440 that we were trying to get to run well through exhaust manifolds. It would go to about 5100 and just lay there. We dropped the exhaust and it went 6500 like it was on nitrous.
I then had a full 3" exhaust on my 572 hemi with some fairly restrictive turbo mufflers. We disconnected them at the headers abd tied them up. Went nearly .4 quicker that night.
Assuming you have the cutouts before that 2-1/2" tube, you're probably good. Otherwise, that small tube is acting like a choke. A dented primary tube is one thing, a choke on the whole exhaust is quite another.

Maybe you are right, the big big problem is/was, that there are no hemi headers available for a 69' Polara or C-Body at all.
Thats why I have bought big Indy headers and start working on them until they have fit.
Maybe you didnt understand me right. Every single pipe that comes from each cylinder is 2-1/2" big. It ends up in a 4" collector and moves on in a 3" exhaust X-pipe. between the collector and the X-pipe are my Cut outs located.

 

[Hemirunner]

I was reading that as it necked down to 2-1/2" at the collector. Big difference. 2-1/2 primaries are huge. Carry on everyone, lol.

 

[Hemirunner]

I have 3.5 inch Xr1s clamped to the collectors so no real exhaust lol.

That's perfect! I always ran it with 3" duals and cut outs. The duals choked it pretty good.

 

[dvw]

Yes there are some videos on youtube, two articles in online magazines (guess it was bangshift and the other one I forgot)
Alright, I keep that in mind.. Maybe I buy a bigger pump right away. Its a never ending story

Why not run the fuel delivery test in post #10 earlier first instead of buying parts you may or may not need? Watch Dave Dudek's Road Runner here, it runs 9.98 through manifolds and 2 1/2" exhaust to the back bumper.
.
Doug

 

[Bigal75]

^ mine was flowing under a gallon in 30 seconds. It wasn't enough.

 

[hemicharger572]

Hi,
yesterday I put the 1250cfm dominator with a 2.5" adapter on the hemi.
It works quiete good. It runs a little rougher then the old carb, but still ok.
It feels like that the dominator have much more power compared to the old 1050cfm QFT 4150series.
But unfortunatlly in 2nd and 3rd gear the rpm stops at about 5200 rpm. But already 700 rpm higher then before.
I contacted the guys from Aeromotive and asked them what fuel pump they would recommend for my set up.

I think I should go with the A1000 or the Black Eliminator https://www.summitracing.com/int/parts/aei-11104
https://www.summitracing.com/int/parts/aei-11101/overview/?retaillocation=int

 

[hemicharger572]

BTW: That old dominator that I have is supposed to be a 1250cfm. But I am not exactly sure.
Maybe someone of you know that.
The only interessting numbers I can find are 9377 2.

 

[Bigal75]

It's rough because it's rich at part throttle.

 

[hemicharger572]

It's rough because it's rich at part throttle.

yes I know, but it works great. I was really supprised when I put it to the floor

 

[Bigal75]

Is it a 2 or 3 circuit?

 

[hemicharger572]

Is it a 2 or 3 circuit?

unfortunatly I have no idea.. I gues its a 2 circuit because its a pretty old carb.

 

[Bigal75]

If you look at the top of it you'll see the air bleeds how many per venturi? 2 is a 2 circuit 3 is a 3 circuit.

 

[hemicharger572]

If you look at the top of it you'll see the air bleeds how many per venturi? 2 is a 2 circuit 3 is a 3 circuit.

Hi,
it is a 3 circuit. On each venturi it have 3 air bleeds.
But the crazy thing is that somebody have removed the intermediate air bleeds on all 4 venturis!!?

 

[Bigal75]

Yes In efforts to lean out part throttle.
Read this, it may interest you. I did the conversion.
http://motorsportsvillage.com/forum/viewtopic.php?t=3742