Based on what opinion or experiences?

My fixture flows carb bodies one barrel at a time..... Which isn't really correct either........ But unless you have a 1200cfm bench...... You do what ya gotta do.

For an approximate wet flow number, I take the dry flow and use .92 of that.

Flowing one barrel at a time, and using the 92% number, an original Holley HP950 (1.375 x 1.750) flows about 860cfm.
Traditional Holley 650's, 750's, 850's(with the chokes) come out pretty close to their respective ratings when tested that way.
The same cannot be said for most of what I'll call the "new design" carbs.

The guy that bought my PS1000 had an annular carb on his. Mine was over a 1/10 quicker. He wouldn't give it back after testing it. The annular is on my shelf here if your interested in it...it's a nice QF...

One data point from some guy with a car that went faster when changing carbs isn't very convincing argument. The annular boosters will pick up a lot of low end torque in a big carb. Your buddy might have lost torque by switching to your carb and since his chassis wasn't very good he ended up going faster.

Thanks, but I have carbs & carb parts coming out my a$$ right now already.

Low end is what he was lacking....If you only have 30cc pumps, you will not catch my PS1000....I had a pair of 50cc pumps and #45 squirters front and rear. He went faster everywhere with mine. MPH picked up, 60ft picked up a bunch, and midrange picked up. Once he bolted mine on, he ended up with traction problems! 60ft went from a 1.58 to a spinning 1.51...He bought new slicks, and he is almost in the 1.49's now..And we are in the heat of the season.

So that is my data point, but we know why that carb worked, and I would buy another with my jetting in a heart beat. We tested it on three engines, it was always the fastest carb.

well to be honest... I don't think the 4500 I have will perform as well as the carb in use. I put an adapter on my 4150 intake and ran our dominator and it actually slowed at Barona. ALSO... the 4500 intake I have was welded up and adapted with not much porting in the plenum area and the port size shape is still that of the craftsman based mill it came off. I will play with it as is with a port match one day. Until then....we'll continue with what we got.

Totally agree, because the best tuned carb on a manifold that is less than desirable in terms of efficiency can be and is slower as you found out......

Thanks for the reply.
I have a Mighty Demon 850 anuular.
(Throttle Bore 1.75 inch Venturii Size 1.560 inch)
The 337 manifold is ported, no room for a 4500 adapter.
Doesn't seem worth the time or expense to pick up 5 hp.

On my 470 the QF 1050-AN (annular boosters) worked much better than the Holley 850 and 950 that I tried. The 950 was converted to annular boosters which improved it significantly, but the QF 1050 was still the best carb.

However, this is just dyno testing where we run the engine from 5000 to 7000. The carbs could behave differently on the street or the track. On the dyno we don't really have a way to test "driveability" issues.

My point finally strikes gold............. a 5000-7000 dyno pull in no way even touches on street drive-ability or low speed manners just like the one you sold Brad I tested. Couldn't even do a burnout no joke but after working the idle, transition and cruise, it's drive able.......And personally hearing about 4150's on Big blocks especially making even 500+ deserves a Dommy especially a 572 like someone mentioned..........CRAZY and leaving a LOT on the table no matter what you heard or read..........PROVEN every day........

My test was downleg vs downleg.

And, fwiw...... I've been testing for, and sorting out driveability issues on the dyno for 27 years.

The dyno can be used for a lot more that wot testing.

I agree that a dyno is a great initial tuning tool but not to be confused w/real track testing and results for a race car/street/strip car that sees idle,transition and low speed driving. I was just hammering home what Andy admitted to about a limited upper rpm dyno run and peak numbers many shoot for but then in the car/truck, problems arise. I respect the testing you, Andy and others do in the name of power and durability and separating fact from fiction so we all can make better choices the first time. I spend hundreds and hundreds of dollars on fuel, oil, plugs etc. to test on the street and track and have learned enuff to have a much better understanding about things that just 5 years ago I had little of...........I do what I do because I love it not for money or glory, I actually LOVE flogging cars and making changes to better their performance..........

I went from Holley 1.563 w/down leg, to 1050 AN , drivability is much better, my engine combo likes it.

Agreed my 1050AN started, ran and drove great after some IAB tuning, jet changes and an IFR change. We might have plugged one or two of the 5 emulsion holes on the metering blocks as well.

OOTB the carb ran poorly at 4200 feet above seal level.

i have one of those Race Demons with the removeable sleeves. i had bought a 1050 kit & changed everything over as prescribed but it was a dog driving around the pits, I rang the Demon help line at the time to see what tips i could get & I was put thru to Barry Grant at the time. He advised me & sent me free of charge, some other sleeves to make it into a 1025 instead. the sleeves had 0.040 more venturie effect. wow, huge improvement over the 1050, the car was so much more responsive & i ran my car at consistant 9.5's for many seasons with that combo. so if you want any 1050 sleeves, i have some going cheap.

The "1025" sleeves were 1.562 as I recall..... The black ones.

In that venturi/throttle bore combo(1.562 x1.750) .....If it was a Race Demon RS it was a "1025", as a Race Demon w/o removable sleeves it was a "1000", and if it was a Mighty Demon it was an "850".

I have a Race Demon RS 950 Annular that I converted to a 1050 down leg.
Drives fine on the street and ran my best times.
I have switched to a Gen 3 Dominator and the test results are not in yet. The new carb was not zeroed in yet.And I haven't been back out to test it .
The engine is a 572" Hemi.
Mark

It's been years since I flowed any of those things, but to the best of my recollection.... They were about 920-930cfm.

The annular boosters were 20-25cfm less.

I had also bought some of the largest sleeves..... I think they might have been 1.590(?).... Silver color iirc...... And they didn't increase the flow at all.

Yep, the 1.562" venturi was the "1025"; still have my black sleeves.

Re the advertised size differences... I figure BG felt if you didn't pay the extra $$$, you didn't deserve the extra CFM!