Do Velocity Stacks really work? The Battle: Dyno numbers vs DragStrip ET's 

They belong on Casper!

On a parallel thought path, we found out in our dirt cars, back when we could run Q-Jets or Holleys, that the Q-Jet preferred a flat bottom breather, and the Holley preferred the radius bottom. I've followed DV's advice on this carb stuff for a bit. It works.

Oh I know they work, 512 CID stroker BBF Ported Factory heads with big valves, Ported Edelbrock Performer RPM. 825 ft lbs Tq. We bought the Bronco on knowing it was Number 3 out of 3 ever made. Rock Crawler, Mud Bogger, and Daily driver all in one. Fully documented on every part tried and what parts worked in the build. The velocity stack through me off on the biggest Edelbrock carburetor made at that time (1990's). We drove the beast home from bottom of Ohio to Mid eastern Michigan. We got better gas milage then my Brother's 1996 4x4 F150 with dual tanks and bone stock EFI 302 in it. Once home? we tried removing the Velocity stack and run it? Nope it didn't want to start and when it did? It ran like crap, I put the stack back on while it was running? And it smoothed rt out back to normal. Definitely they work.

This is something. Two completely different tests, one static, one dynamic, both resulting in increased HP and TQ. I wouldn't say 100% reliable but the numbers are what they are. Thanks Andy, another great thinking man's video...

Thanks Andy. The Windsor sound fantastic.

That being said I will have to get DV's book to go with ny old original book that covers every type of Holley ever made. I'm going to try and get you to make a new video dealing with the C/MP on your truck and what all the letters are and what the heck that they mean. I'm going to hope you will entertain me on this one and have a great day today as I enjoy your video for the second time this morning

Andy, your immense carburetor knowledge and great videos have inspired me to build a set of 1850 holley 600s for my tunnel ram equipped 377 Sbc. I went with the allstate carb conversion annular boosters and have machined the bodies for removeable air bleeds. Id love to get your advice on where to start for initial bleed sizing. I have a general idea but am not sure. Thanks for your time, effort, and awesome videos!

that truck sounds REALLY good too

One of Goals I am working on, and Dyno test TR on a 615 hp 354 ci Cleveland, Stacks Look Killer, thanks for the vid Andy

Great video brother! Love seeing the results! Great find on the stacks!

I bet if you had individual o2 sensors you would see more even fuel distribution across the cylinders with the velocity stacks by giving the air more time to find where it belongs after making the turn into the carbs.

Great video. I wonder if a rear facing cowl style scoop is better than a front facing scoop since there would be less turbulence over the carb.

Impressive results

You are correct Andy almost no one talks about or even knows about booster buffeting and even better is if you can isolate the filter from under hood air that can easily reach 200 degrees ... we know this is why DV has put so much effort into the Mustangs air box ... would love to see dyno pulls from under hood and outside air test ... thanks for great info

Useful info, based on facts 😎👌 good job as usual. Cheers from Italy 👋🇮🇹🇺🇸

Awesome Video! 🔥 In the Midst of designing something for My 440! I like how you said with air filter it slows it down and distributes!

Something I remember my telling years ago about straightening out the air as it enters the carb vs the turbulence of the air under the hood going down the track. Added benefit preventing potential trash causing engine damage.

Real world info. Thanks

Thank you Andy for sharing your video and the convincing results!

That’s a great video Andy, very informative. There was a video on RU-vid by horsepower depot that races the FAST class, he was running really quick and his competition accused him of running without an air filter. He actually forgot to put it on in one of his videos, when he added it, he was actually faster lol

I saw a 480 bbc dyno 776 hp crank and run 10.2 with 88 jets in twin 1050 s.After re jetting it normal 94 around,it went 9.51 in a 3200 lbs 55 chevy here in cold Finland.

Every little gain in numbers adds up down the track 👍

I think I’m remembering DV saying velocity stacks don’t help in a video. I always ran a stack and filter on my sbf powered sand drag car.

Ive been looking at those K&N Velocity stacks. Man they aren't cheap at all.. LOL.. Thanks for the info, Velocity Stacks are the ticket.

This is a good video. I was thinking 3hp isn't a definitive win on the dyno. For it to be a trend I would think that you would want to do maybe 3 runs without, then 3 runs with and finally another run without. Even driveline oil temp can be a factor on a dyno. I did find it interesting that running filters makes the engine run generally leaner. I had thought that it may give it a stronger signal threw the boosters. But I guess as the bowl vents are also subject to the same slight vacuum them it would cancel it back out. I have that exact book of DV. I intend on reading it cover to cover before I start tuning the carbs on a project car. I did read the sizing section when choosing the carbs. Thanks for posting!

It doesnt matter if they work , its the look . It looks so cool , who cares !

I’m curious to see what the strip results would be running stacks only, NO filters.

Initially? My guess was stacks lose 10hp or so - something along the lines of air bleeds behaving differently with stacks on. Then, engines do what they usually do: something else. Reminds me of how economists are always "surprised" in a way. Testing beats theory on a regular basis. Good work.

Would like to see a”boom” exhaust NASCAR style and a newer NASCAR exhaust in a 200mph air stream and with out to see what the difference really is.

Thanks for sharing, all the best to you and your loved ones

Nice video! Thank you for doing this! I did notice a quicker response, and a better, (put you into the seat) felling on my Scamp with the Velocity stack, compared to just an air filter.

From what I've seen with Frieburger and Dulcich doing tests you can't run too big of an air cleaner but you can definitely run one that's too small. And no open top K&N. And now after watching the video, Frieburger and Dulcich were very much static on an engine dyno vs running down the track with their testing. Great comparison and that's a good bit of power difference.

I ran stacks on a drag bike along with a lot of testing. I kept having problems with the motor going lean on the top end. I changed carbs three times, rejeted over and over, added spacers between the heads and carbs but nothing helped. Then I ran into a guy running stacks on a street racing bike, and I thought I would give them a try. They changed everything and the bike started pulling hard on the big end. They made a huge difference and my carbs were laying on there side facing the rear of the bike. It must have been a making a lot of turbulence near the opening of the carbs at higher speeds and causing all the trouble. Good video on a good topic.

Good video. Do more like this.

Air going across a carb will only affect the vents, not the boosters. The boosters are way down level with the venna contracta. The stacks help turn the air a little but manly stabilize the turbulence around the vents. The same thing can be accomplished with a proper flute connecting the vent tubes.

i have used various cleaner setups, and every setup i personally felt the stacks always helped out when i changed the hood on my car and went to low profile high flowing 14*4 i felt like i lost something, like crispness so to speak i love them, especially with the KN race air filter (no oil) although, keep in mind, you may need to "tune" depending on your air setup again i always felt crispyness

i am a little confused. was this video more about comparing VelocityStacks vs No-VelocityStacks or comparing Airfilter vs No-Airfilter?

Try them on the Edelbrock carbs you have installed on Casper. And do a chassis Dyno. And show us the before and after. Im curious if the combination goes hand in hand.

It makes sense that they work, racers used them for years. I always wondered why they fell off in popularity.

Aren't the individual pipe risers from the top of individual Weber carbs and or on top of old school fuel injection setups? They aren't always straight verticle pipes but sometimes they may have a bend at the top facing forward example, the Munster's Dragula coffin dragster, and sometimes they are at opposing tilted angles but dtill straight pipes. A lot of people cut a section out of the hood of their car and the stacks would stick out through the hood the way a blower intake might.

I wonder how the Ole stub stack would do the same ? For those without hood clearance?

Good morning Andy

great vid.

Sweat sounding truck Andy!

"how do they stack up . . ." I see what you did there! 😜

Are you gonna rematch uncle Tony in a race again Andy

GOOD JOB great info and usefull to me

It's more of a case that the unfiltered combination lost 20-25hp at the track compared to the static dyno test, try flow testing filter lid heights from the top of the carb, even without a filter in place the lid itself starts to effect flow through the carb under 3'" of spacing.

hey a while ago you said if you buy a Casper t-shirt send me the picture of you wearing it beside your ride I will post it to a video have you done that yet, or am I just walking around wearing a Ford shirt for kicks and giggles,🤣🤣 I do like my shirt and that is a cool old Ford truck

I have a good Holley tune and rebuild book

Andy, your dyno and drag strip tests were incomplete. Air filters will restrict air flow to the carbs. I suggest that you retest without air filters on the velocity stacks. Then richen your carbs and test again. You will now see the encreased power gains that velocity stacks will provide due to increased laminar air flow.

Another Great video Andy. I love watching your Channel and videos. Easy to watch you come across great, a very fun down to earth channel with knowledge and imformation that I can trust. RU-vid unfortunately is full of fake and bullshit just to get views. Since finding my Biggest Mentor D.V on RU-vid , I was lucky enough too stumbled across your's & Charlies great channels.

You should probably say the car will run better with an air filter if it's properly sized meaning a big one

To ME, It looks like IF you had your car "dialed in" ie; bracket racing🤔 This could be a quick swap to gain a tenth in "a clutch situation" where that tenth could make the difference between winning and losing😉🤷🏻‍♂️

Andy, your truck has a real nice note. Can I ask what mufflers you are using. Mike

Huh:) Thanks Andy

That's interesting, My 86 fox had a very mild 306. I tuned on the cab until the throttle response was crispy critter at any speed. this was with a c-4 3500 stall and 3.73s. it was my daily driver. I found a stack just like the ones in this video and thought it would look cool. After installing it I got what I would call the du-waa throttle. when you wack the gas it would bog for just a second or two. I never ran it down the track with it on so I can't speak for that but I took off about two days later.. I would love to here your thoughts on that.

1:00 "Baseline without Stacks/Filters" Is this meant to say that you ran with neither the stacks or filters?

You must have a low pressure area when you're moving. Just enough to give it more air but not fast enough to blow past it

Time to call out Tony again if he is not scared. Don't sleep again at the starting line. I bet he will chicken out this time.

Open velocity stacks without a scoop can actually siphon gas out of the top, the air across the top can have a pitot effect

I'm still out on this. It's such a small number that it's within the margin of error.

✊🏼⛽️👍🏼

So what made the difference, the filters or the velocity stacks ?

Sucks you did not test the stacks without the filters.

Was barometric pressure the same?This increase is easily just better air.

Please clarify. Did you run the truck at the track with a filter and no velocity stack and then run the truck with a filter and a velocity stack?

what model number are they? what is the part number for the filters?

momma says God gave us velocity stacks so we could get to church faster.

Anyone remember the engine masters air cleaner test? I think a metal salad bowl made the most hp😂😂😂

nice

Does the height make a difference? I've seen short ones and tall ones. 🤔

2 miles per hour is a big difference how many Nascar drivers do you think would like to see two more miles an hour

ANDY I WAS THINKING ABOUT USING THOSE SAME FILTERS BUT THEY SEEM AWFUL SMALL - HAVE YOU TESTED WITH ANYTHING A LITTLE TALLER OR WIDER?

WHAT DID THE 406 SLEEPER RUN?

🥝✔️😁