Engine Masters DP VS test

[Tom68]

Do we really give up on a carb test when the DP gets it's high speed enrichment from discharge nozzle pull over and the vac sec is leaner so we just give up and say the DP makes more power for the same airflow ?

That is what I saw the other day right ?

[HQM383]

This?

https://youtu.be/G1pr3zVmW3g

[Tom68]

This?

https://youtu.be/G1pr3zVmW3g

Yer that's it, I just watched bits, hard to sit through the whole thing.

Screenshot 2022-11-02 195320.jpg

Although their couple of seconds of Gopro proof didn't show the high speed enrichment.

Carburetor Confusion! What's the Best Setup Engine Masters MotorTrend.mp4_snapshot_04.17.943.jpg

[HQM383]

This?

https://youtu.be/G1pr3zVmW3g

Yer that's it, I just watched bits, hard to sit through the whole thing.

Screenshot 2022-11-02 195320.jpg

Usually an excerpt from a longer, more detailed episode. Maybe someone here has a paid up subscription and has sat through the whole thing. Either way I can’t be convinced it’s the secondary squirters accounting for the extra hp. They do not mention it in this vid but I doubt they would have done all that carb testing and not dialed in the AFR for each. Notice each carb type test had air flow of something like 689cfm. The carbs would not be near their limit with that flow. Do we know if the secondaries on the vac sec became 100% open?

[RDY4WAR]

I watched the whole episode. The vacuum secondaries did not fully open. Being on the large side, the engine only pulled them open as much as needed. They did play around with secondary opening rates for both, I believe. They also dialed in the jetting / AFR for each.

[rgalajda]

Did they run the hat on both carbs ?
Air flow was identical they say.
The DP carb flowed more fuel is they're reasoning ?
We did every little tweak they say. ????????

I have very little faith in these guys . Mostly commercialization.
More respectable people have done this test on dyno and track with different results.

[cab0154]

Could be emulsion differences in the DP too, especially in the HP....

[RDY4WAR]

They do get things mixed up at times. They've also been flat out wrong about some things and misunderstand what's happening with others. Some of the topics they discuss are just way too complicated to summarize in a 30 minute episode swapping 2 or 3 parts. There's seminars lasting hours or days going over just 1 area of one topic.

I've also wondered how many "tests" they run off screen that don't make the final cut either due to not achieving a certain result or the results make a financial sponsor look bad.

I don't mean to knock Dave and the Steves themselves. They're decently smart guys who know what they're doing at least somewhat of the time. I just feel like efforts to simplify things often backfire. The more you try to simplify something, the more open it becomes to interpretation. In the age of gullibility and instant gratification, simplifying things tends to create more myths than it busts. However, trying to spell out things often doesn't work either as that need for instant gratification means a short attention span.

[rfoll]

I've posted this before somewhere, but some time back I was using a 3310/780 carb. I had the lightest spring in the vacuum pot, even went so far as cutting a coil off one. At the time I was chasing 60' times. I stumbled into a deal on a 4780/800 dp carb. They have the same venturi and base plate sizes. At the most, the dp was half a tenth quicker, but I wasn't sure it was real. Atmospheric and track conditions can change et that much in the time it takes to make a carb swap. The engine was a 412 or 415 sbc, I don't remember which, car was running 11.0 or so.

[midnightbluS10]

Do we really give up on a carb test when the DP gets it's high speed enrichment from discharge nozzle pull over and the vac sec is leaner so we just give up and say the DP makes more power for the same airflow ?

That is what I saw the other day right ?

Huh? What are you talking about? What's DP? And please try to separate compete thoughts instead of running everything into a single sentence. 45 words is far too many for 1 sentence. Especially when it contains 2 separate sentences ran together with "and".

Seriously. Consider that others have to read and decipher this stuff.

[mt-engines]

Do we really give up on a carb test when the DP gets it's high speed enrichment from discharge nozzle pull over and the vac sec is leaner so we just give up and say the DP makes more power for the same airflow ?

That is what I saw the other day right ?

Huh? What are you talking about? What's DP? And please try to separate compete thoughts instead of running everything into a single sentence. 45 words is far too many for 1 sentence. Especially when it contains 2 separate sentences ran together with "and".

Seriously. Consider that others have to read and decipher this stuff.

You out of all people should know what DP is.

[HQM383]

...... The more you try to simplify something, the more open it becomes to interpretation. In the age of gullibility and instant gratification, simplifying things tends to create more myths than it busts. However, trying to spell out things often doesn't work either as that need for instant gratification means a short attention span.

I wonder how many watching that episode will go out and up the size of their secondary squirters looking for power based on their simplified conclusion

[Tom68]

Huh? What are you talking about? What's DP? And please try to separate compete thoughts instead of running everything into a single sentence. 45 words is far too many for 1 sentence. Especially when it contains 2 separate sentences ran together with "and".

Seriously. Consider that others have to read and decipher this stuff.

Thanks for the English lesson, yer can't read my own stuff half the time, left school early, didn't like lessons.

[skinny z]

Do we really give up on a carb test when the DP gets it's high speed enrichment from discharge nozzle pull over...?

With all due respect to the trio, that's when I gave up on the video.

[barnym17]

Could the difference simply be a mixture distribution issue?If the vacuum secondaries were not op÷n all the way vs the double pumpers that were?Air and fuel mixture direction into the plenum would be affected.