Don't read if you're close minded

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273 said:
When I said least restriction, I didn't mean no restrictions, I meant generally the least restriction that will perform how you want. Whatever that want is.

Eg. Say 650 gives you everything you want a 750 would only gain a couple of hp and a 500 kills 20 and gives a similar experience driveability wise. To me the 650 would be the least restriction that gives you what you want, but now lets say the 750 actually gains 15 hp across the meat of the powerband but gives up some driveability, now some wouldn't overly care about the driveability so the 750 is the choice and for other on the same combo would prefer the 650 but there's no reason to choose the 500. The choice is depending on what's needed/wanted 650 vs 750.
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I guess so but I actually have metrics and quantifiable data to go by. What I can't do is determine a persons toleration/expectation of how that engine "drives". Your example of a 750 gaining 15hp will absolutely give up driveability. My threshold for moving to a bigger carb may even be based on when the boosters are activated and theres just no way to calm the fuel flow down when at a cruise RPM. A 500/4412 will actually cost 60-70hp on a 500hp capable build. Fact is I'd give up 20hp for better start/part throttle/tip in/cruise. Why? Because when you have all those other qualities-the car winds up faster anyways.

Years ago there was an amazing CarCraft article where the author put a car on the chassis dyno and tested I think 4 carbs from a 650-950? Not sure about that but.... The smallest carb made the least HP/TQ and the largest made the most, just like you would expect. Then he took the car to the strip and raced them while monitoring intake vacuum. Guess which carb went quickest? Yep the smallest one. Yes the MPH fell a little but it was very little IMO. Also the smallest carb created the most intake vacuum by a vast margin. I remember the take away and at the time I was dumbfounded. Those types of articles were few and far between that mirror what I've seen IRL. J.Rob
 
You've run a dominator on a dual plane?
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Well, you got me there.

I have run a 4500 on a dual plane, but it was an old BBC intake made for a 4500.

So, no…….. I guess I haven’t done the same test that Eric did.

Though I’ve done it numerous times on single plane manifolds.
 
RAMM said:
I guess so but I actually have metrics and quantifiable data to go by. What I can't do is determine a persons toleration/expectation of how that engine "drives". Your example of a 750 gaining 15hp will absolutely give up driveability. My threshold for moving to a bigger carb may even be based on when the boosters are activated and theres just no way to calm the fuel flow down when at a cruise RPM. A 500/4412 will actually cost 60-70hp on a 500hp capable build. Fact is I'd give up 20hp for better start/part throttle/tip in/cruise. Why? Because when you have all those other qualities-the car winds up faster anyways.

Years ago there was an amazing CarCraft article where the author put a car on the chassis dyno and tested I think 4 carbs from a 650-950? Not sure about that but.... The smallest carb made the least HP/TQ and the largest made the most, just like you would expect. Then he took the car to the strip and raced them while monitoring intake vacuum. Guess which carb went quickest? Yep the smallest one. Yes the MPH fell a little but it was very little IMO. Also the smallest carb created the most intake vacuum by a vast margin. I remember the take away and at the time I was dumbfounded. Those types of articles were few and far between that mirror what I've seen IRL. J.Rob
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If the big carb made more power and went slower that’s a chassis/converter gearing issue.
 
toolmanmike said:
A 496 could easily use a Dominator anyway. So the base carb was a 1050 as was the Dominator. Pretty much apples to apples there. The intake was an Air gap and when the dumb *** called it a "Eldebrock" I shut off the video. He lost me on that one.
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There are very few people who would agree with you that Eric Weingartner is a dumb ***.
 
Yeah, the small carb was faster over the quarter than the Dom....That is because the engine has to get to 4000 rpm before it can get to 6000 rpm where the engine might use the extra flow of the Dom...
 
RAMM said:
Years ago there was an amazing CarCraft article where the author put a car on the chassis dyno and tested I think 4 carbs from a 650-950? Not sure about that but.... The smallest carb made the least HP/TQ and the largest made the most, just like you would expect. Then he took the car to the strip and raced them while monitoring intake vacuum. Guess which carb went quickest? Yep the smallest one. Yes the MPH fell a little but it was very little IMO. Also the smallest carb created the most intake vacuum by a vast margin. I remember the take away and at the time I was dumbfounded. Those types of articles were few and far between that mirror what I've seen IRL. J.Rob
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Wasn't this article was it:

How to Pick the Best Carburetor for a Street/Strip Car
 
when i put the 440 in my 65 dart i borrowed a 750 vac holley til i found a carb. my mate needed it back and with money tight i bought a cheap 600 vac holley. the car noticeably nosed over as it got close to 5000rpm. however it was smoother and much more responsive up to that point, oh and a lot more economical which helped as it was my daily.
neil.
 
mygasser said:
that'd be fine with a 4/71 supercharger squeezed in between, lol.
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Yeah, I'd love to do one with the AUssie blower on it, but alas, It'll probably never happen. That's ok. I'm pretty stoked doin what I'm doin.
 
Bewy said:
Yeah, the small carb was faster over the quarter than the Dom....That is because the engine has to get to 4000 rpm before it can get to 6000 rpm where the engine might use the extra flow of the Dom...
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IMG_0993.jpeg
 
It’s pretty clear to me that some of the small carb guys didnt watch the video because they would’ve seen the graph.
BCD0F27A-CD27-40D4-9FA7-D0C09799D300.png

That’s what was surprising. The Dominator didn’t just make more peak. It crushed the 4150 everywhere. And @Bewy don’t you think most engines of this caliber or this much camshaft would have at least a 3500 converter behind em? Who cares what this type of engine does at 1500? No one, is the answer.
 
I'm gonna have to come back and read this whole thread, but it comes down to the specific combination, as to what it likes.
I've seen tests where a 1050 dominator was no better than a (supposedly 1050) 4150.
Also... what spacer/adapter was used? Could definitely have an effect.
 
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A 4150 Holley 1050 DID NOT flow nearly as well as a 1050 Dominator
on my friend's Wet flow Carb Bench.

I have no explaination on how Holley could rate them the same except if
the have different standard that they go by?
 
33IMP said:
I'm gonna have to come back and read this whole thread, but it comes down to the specific combination, at what it likes.
I've seen tests where a 1050 dominator was no better than a (supposedly 1050) 4150.
Also... what spacer/adapter was used? Could definitely have an effect.
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On the Dom he used an HVH 4 hole tapered 4150-4500 adapter and he said he’s never seen it loose power. It’s usually worth 10. So maybe it’s more the spacer than the carb.
 
GTX JOHN said:
A 4150 Holley 1050 DID NOT flow nearly as well as a 1050 Dominator
on my friend's Wet flow Carb Bench.

I have no explaination on how Holley could rate them the same except if
the have different standard that they go by?
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I have Never believed the hokum that a 4150 could flow as much as a dominator..... except for that weird little 750 one.
Explanation? Advertising hype. It doesn't HAVE to be truth.
 
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TT5.9mag said:
On the Dom he used an HVH 4 hole tapered 4150-4500 adapter and he said he’s never seen it loose power. It’s usually worth 10. So maybe it’s more the spacer than the carb.
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Agreed. Imo, the test is,only semi valid. Better would be to use similar manifolds dedicated to the carb of choice...... or best, a manifold for a dominator that has stud holes for a 4150 too, so both can be run on the SAME manifold.... without an adaptor or spacer.. or a 4150 with slots in the baseplate for a dummy intake.
(Note, if I make a stupid comment here, it's cause I haven't read this whole thread yet... but I will!)
 
Bewy said:
Yeah, the small carb was faster over the quarter than the Dom....That is because the engine has to get to 4000 rpm before it can get to 6000 rpm where the engine might use the extra flow of the Dom...
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Not true, if you have a stick.... or a 5500 converter (speaking strictly drag racing).
 
I ran a gold claw on my car , the one with the replaceable sleeves. I thought it had 850 sleeves in it, and the car ran well with them. (I also used a 2" open spacer). Imagine my surprise when I did some research, and found they were 770 cfm. I never did change them out for the bigger sleeves I have.
 
RAMM said:
I never said it was wrong, I'm saying its like chasing a big flow number---If you put 300cfm capable heads on a 450hp engine--that engine will not drive as well as an engine with 225 cfm heads on it making 450hp. The pumping loss most are so focused on is because its low-hanging fruit--easy to remedy. I've seen it so many times I've lost count. Guy tests his engine and we try multiple carbs. Guy leaves and tries biggest dyno sheet carb, Guy calls and complains about how it just doesn't seem to perform well (idle/part throttle etc...) Guy says yeah it pulls real hard when hes got the room to really stand on it. Guy puts on smaller carb that we tuned and produced maybe as much as -1.7" to -2.1" that cost 4hp @ the last 500rpm. Guy calls and tells me it starts better and how its got a stable idle now, part throttle is snappy, and pulls everywhere and he can't tell the difference at the top and Guy actually thinks it is faster now. Cuz it is. But then again my carb guy and I have really been looking at this and documenting this trend for years. A "slightly smaller" carb is always better in the actual real world. J.Rob
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I would assume that an engine with 225 cfm heads and 450hp, would need a bunch more cam to reach 450, than an engine with 300 cfm heads. I would bet the milder cam/better head combo will be a better driver.
 
PRH said:
Well, you got me there.

I have run a 4500 on a dual plane, but it was an old BBC intake made for a 4500.

So, no…….. I guess I haven’t done the same test that Eric did.

Though I’ve done it numerous times on single plane manifolds.
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Must have been an old Eddie C-454 intake. Would have made a good test piece for this test, with a 4150 with slotted base to bolt directly onto a dommy manifold.
 
This should throw a few peeps in to a tizzy. How about the same test on a small block? 406cu in.

 
And just in case anyone reading is lazy and doesn’t watch the video I’ll post another graph.

066D86F5-CC92-4CDC-A82C-163A7BB74578.png
 
GTX JOHN said:
A 4150 Holley 1050 DID NOT flow nearly as well as a 1050 Dominator
on my friend's Wet flow Carb Bench.

I have no explaination on how Holley could rate them the same except if
the have different standard that they go by?
Click to expand...
Best I have been able to come up with is the ratings such as 650, 700, 750 etc are mostly approximations for purposes marketing and sales.
As I recall looking at the 4776+ series and comparing with their vacuum secondary counterparts and found the same bore, venturi, booster were rated 50 cfm different.
 
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