CARB SHOOTOUT-2 BARREL VS 4 BARREL, ORIGINAL 4412 VS XP4412 VS QF4412, 650 v 750 CHOKE v 750 v 950

HOW MUCH BETTER IS THE NEW 4412 XP? HOW MUCH MORE DOES A 4 BARREL CARB FLOW THAN A 2 BARREL? WHy IS THE FLOW RATING DIFFERENT FOR A 2 BARREL THAN A 4 BARREL? HOW MUCH LESS DOES A 1 BARREL FLOW? WHAT HAPENS IF I GO PAST WOT? CHECK OUT THIS VIDEO WHERE I FLOW TESTED 8 DIFFERENT CARBURETORS AT THE SAME DEPRESSION. HOW DO THEY REALLY COMPARE IN FLOW? IS THE NEW XP HOLLEY 4412 REALLY BETTER THAN THE ORIGINAL? HOW DOES THE QUICK FUEL VERSION STACK UP?

[JohnnyAnderson]

your pop ups at the end keep us from seeing the final numbers.... just throwing that out there!
GREAT video! cant wait to see these on a engine!

[lazyhoundracing]

Thanks for doing a test for us old school guys that don't want to question the laws of physics.

[johnparrish]

Damn, I sure wish you had thrown a Qjet and an AFB in there for fun....lol
Great test.

[Apachefog]

I was really hoping to see a 500cfm 4bbl tested so we had a direct comparison between the 2 and 4 when the published numbers are the same.

[waynep]

Richard on the engine dyno or with A/F ratio sensors installed I bring up the rpms till I see fuel trickling from the primary boosters then back off till it's not. Look at the A/F ratio. If you are lean go to bigger IFRs. Try again . I got to 0.036 IFRs on a 40 over 429scj and the car owner complained he could not pull away from any stop sign or red light without spinning the rear tires. Holleys ship with a 0.031" IFR because that is what their computerized air flow bench is set for. 0.031 is good for a 327, 331. A 0.032 is good for a 347 to 365.
Try it. Be totally amazed you can do dyno runs from idle without needing to start the run at 3000 rpm. Drivability is improved as is fuel economy .

[andrewdenmark]

Out here doing the lords work thanks Richard

[romeo]

Love your videos. I have a video suggestion. You should do a dyno comparison video on the Holley Sniper EFI and the FiTech on a 302. Thanks for the content! Keep them coming!! Looking forward to that SHO video you keep teasing.

[deanstevenson]

Courageous Communication with the Community. Great Conversation topic, you won't regret it, Richard. PS, removing the choke horn takes 1 CFM off the peak flow. 🥝✔️

[kelvinhayes]

Like the video. I have a Holly 600 on my 1970 Chevrolet C10. You showed some good carburetors information 👌thanks.

[jimjungle]

I was always curious comparing the old 850 DP (4781?) to the 950HP and the 1000HP. The 950HP is hybrid carb, with an 850 throttle plate and a 750 or 800 main body, although the main body is, 'enhanced" compared to the older models. The 1000HP is a straight 850 with an enhanced main body. We always got more power with the 850DP over the 950HP, but the 1000HP would top that. I wonder how the flow of the 950HP compares to the 850DP 4781. In our experience, the 850 ran as a bigger carb than the 950. I did run a 340 Mopar block with a ground down 360 crankshaft with a 500 two barrel in circle track. I balanced the racing flywheel to the externally balanced 360 cast crank, with a 360 balancer and the cast crank held up fine. One thing about circle track is, you aways find the weak parts and what will break. Went from 340 heads to W-2 heads and intake on that one too.

[johnmurray]

The explanation I remember hearing for the different flow test depressions was that in the early days of the four-barrels the flow benches of the time simply didn't have the capacity to test the big four-barrels at 3" hg, hence the decision to rate them at 1.5".

[larryw]

This would be a excellent way to test and show how vacuume secondary carbs work and can be tuned by changing secondary springs!! Hint hint nudge nudge!

[mb-fsyo]

Didn’t get some of the listings at end because of ads

[hugieflhr]

Nice catch with the over run butterfly

[johnlewis]

That's helpful information! Thank you!!!

[exploranator]

"Now we're talking about big power" ( 1 barrel carb. I predict 125cfm)

Mercury is Hg, not Mg.

I think people would like to know for once and for all how much help a vel stack or those little individual per-throat stacks help flow. However, you are going to have to run the flow bench at far higher depression levels to more accurately mimic the suction of a big engine inhaling through them. Did any of the carbs even get their "rated" flow?

I'd like to see the flow go supersonic through the 1-barrel, or all of them, as that might REALLY aid in atomization a departing shock wave just as the fuel leaves the booster venturi, but to have an efficient carburetor at mach 1, the transition from ambient to venturi to booster would have to be graceful indeed.

Also, the vel stack with some filter in it, such as a semi-conical K and N that just fits inside the stack, for aesthetic reasons. It would have inverse cone and an outer cone for maximum surface area.

[bdugle]

Banners at the end covered up all the data!

[supertruckertom]

Hmm. Weber carbs have replaceable venturi..
How about matching the carb flow to the head flow for the quad Weber on a Ford in a Cobra or GT40 combinations.
Also Individual runner EFI modern equivalents.

Since you have the Weber flow bench adapter

[dresdensvo]

And Holleys 500 2bbl is now over $400 , some of the 4bbls are cheaper . I really like the 500, they bolt on old Fords .

[charlesgraham]

thank u again for taking time to make these videos for us to come learn on. some of ur trolls make me laugh. we didn't see the numbers ur lying. lol why would u lie, i don't see the point of lying, plus u don't come across as the lying type. again, thank u for ur time.