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The S is Silent
01-27-2006, 02:13 AM
My little brain is moving right now, so I can't sleep.

Corky says that optimal is a transition from an inlet 3 times the diameter of the runner to the size of the runner with an outside radius of 1D.

Does anybody know anything about velocity stack profiles, and what they should be? Is any transition better? What shape works?

Has anybody cut open a 2 piece intake? What do the internals of those fellers look like? Are there improvements to be made by fabricating a new plenum?

MOPAR2YA
01-27-2006, 02:47 AM
Be patient, new 2 pc upper plenum will be arriving at FWDP soon. We are sending a functional/finished prototype for her approval in about the next 2 weeks. The 1 pc intakes will follow after those, as will 16V Lotus intakes. Hybrid intakes are on her shelf now.:thumb:

glhs875
01-27-2006, 08:43 AM
My little brain is moving right now, so I can't sleep.

Corky says that optimal is a transition from an inlet 3 times the diameter of the runner to the size of the runner with an outside radius of 1D.

Does anybody know anything about velocity stack profiles, and what they should be? Is any transition better? What shape works?

Has anybody cut open a 2 piece intake? What do the internals of those fellers look like? Are there improvements to be made by fabricating a new plenum?


I think velocity stacks is a very good way to go if done properly. The internals of the 2 piece intake can be improved upon with a cutom upper. I plan on doing that. What I have in mind is making a new upper flange with some velocity stacks built in and getting the flange just right before the plenum is welded to the flange. For the plenum I will not only make it bigger, but will concentrate on equal flow distribution, as I have noticed a little variation in stock form. With no added runner length from a custom plenum the runners will be around 9" in length instead of 12". That should shift the rpm breathing up the scale some. These kind of mods should make the 2 piece a darn good intake in my opinion anyway, and I think it would take a complete custom intake from scratch to beat it.

The S is Silent
01-27-2006, 09:22 AM
My idea was to do something similar. Get the velocity stacks machined out of one piece, then when those are perfect, having my fab guy weld the plenum on. I was thinking about ways to make a larger plenum fit in an L body. Larger flat oval shaped plenum maybe. I was hoping for a way to make it center feed, but I don't know how possible that will be in an L-body. How tight is the stock 2 piece in an L? About how much more room do I have to work with towards the firewall and between the top of the manifold and the hood?

Does anybody know where I can get a large brick of solid aluminum? 2x2x8 inch, or maybe 2x3x8 inch?

GLHSKEN
01-27-2006, 09:26 AM
Manifold to hood... NONE... you have to cut the hood vent drain pan as it is. Manifold to Firewall.. bout 1.5-2".

The S is Silent
01-27-2006, 09:46 AM
Manifold to hood... NONE... you have to cut the hood vent drain pan as it is. Manifold to Firewall.. bout 1.5-2".

Thanks Ken...that's what I seemed to remember on the hood...but I wanted to make sure.

glhs875
01-27-2006, 01:41 PM
Manifold to hood... NONE... you have to cut the hood vent drain pan as it is. Manifold to Firewall.. bout 1.5-2".

Yea, but with a 3" to 4" cowl hood scoop, a whole new world is opened up!!

altered7151
01-27-2006, 02:07 PM
I think the way to do it is get like 1" thick aluminum plate (hmm I just happen to have a whole box of blanch ground aluminum plate, .001 tolerance) and machine the velocity ports into that plate, then make a sheet metal plenum fit that plate. I will get out my fluid dymanics book when I get home, it has some good illustrations of different types of air intakes and the restrictions of each. I'll scan in some pics.

The S is Silent
01-27-2006, 02:15 PM
I think the way to do it is get like 1" thick aluminum plate (hmm I just happen to have a whole box of blanch ground aluminum plate, .001 tolerance) and machine the velocity ports into that plate, then make a sheet metal plenum fit that plate. I will get out my fluid dymanics book when I get home, it has some good illustrations of different types of air intakes and the restrictions of each. I'll scan in some pics.

That's the idea. I was looking at it today, and 2" thick would be mucho overkill. There's a guy around here that owns a multi-million dollar machine shop and can do the CNC'ing of the stacks, and other that can do the welding. I think it'd be a cool intake.

glhs875
01-27-2006, 03:03 PM
I think the way to do it is get like 1" thick aluminum plate (hmm I just happen to have a whole box of blanch ground aluminum plate, .001 tolerance) and machine the velocity ports into that plate, then make a sheet metal plenum fit that plate. I will get out my fluid dymanics book when I get home, it has some good illustrations of different types of air intakes and the restrictions of each. I'll scan in some pics.

Now your talking! Iam interested in a little of that aluminum plate you got. Enough to do what we are talking about, how much $?

The S is Silent
01-27-2006, 03:08 PM
Now your talking! Iam interested in a little of that aluminum plate you got. Enough to do what we are talking about, how much $?

+1 I'd also like a couple of pieces if you can.

altered7151
01-27-2006, 03:39 PM
Let me pull the box out when I get home. I'm pretty sure the plates would be wide enough, and if they are there should be enough material to do 2 intakes per plate. I got them from a guy that was building super-high dollar desktop cigar humidors. They were all super high precision cnc'd aluminum. He had these plates custom ground, so they would be super flat and perfect for doing an intake. Actually now that I think about it, I'm pretty sure that he said the were actually ground to within +/- .0001 tolerance, not .001.

altered7151
01-27-2006, 05:52 PM
Ok, went home for lunch and pulled a plate out. They are 10"x14", but bad news is they are only .475 thick, for some reason I remember them being thicker. But since they're all so flat, you could weld two together, or cut out velocity stack rings and weld them to the base and blend them. I'll get some pics of them tonight.

glhs875
01-27-2006, 06:34 PM
Ok, went home for lunch and pulled a plate out. They are 10"x14", but bad news is they are only .475 thick, for some reason I remember them being thicker. But since they're all so flat, you could weld two together, or cut out velocity stack rings and weld them to the base and blend them. I'll get some pics of them tonight.

That could still work out good. You could blend the plate into the runners of the lower, and get the desired effect no probem. Iam still interested in buying at least plate one from you.

altered7151
01-30-2006, 02:50 AM
That could still work out good. You could blend the plate into the runners of the lower, and get the desired effect no probem. Iam still interested in buying at least plate one from you.

Hey sorry I didn't respond, kinda forgot about this thread. If you guys want plates let me know. I was thinking like $30 shipped for a plate. I can get some pics if you would like.

glhs875
01-30-2006, 09:03 AM
Hey sorry I didn't respond, kinda forgot about this thread. If you guys want plates let me know. I was thinking like $30 shipped for a plate. I can get some pics if you would like.

Do you have paypal? So they are 10"x14"x almost 1/2" thick?

The S is Silent
01-30-2006, 11:01 AM
I'm looking for something thicker. I'd rather machine it out of one piece.

glhs875
01-30-2006, 01:30 PM
I'm looking for something thicker. I'd rather machine it out of one piece.

I bought 2 plates. But I will only use one per manifold. With the .475" plate and with the stock flange thickness, I feel there will be more than enough material to get the desired effect.

Phreakish
01-31-2006, 12:20 AM
for a velocity stack, you can have a contraction ratio of just about anything (ratio of inlet area to throat area), and it can contract EXTREMELY fast without major issues - most of them are restricted by space concerns...

Take a look at the face of a wind tunnel, they have HUGE openings for small test sections, ever wonder why? ;)

Just as long as you have a decently smooth surface, you'll get the benefits of increased flow velocity...

SMPerformance
01-31-2006, 08:20 AM
Does anybody know where I can get a large brick of solid aluminum? 2x2x8 inch, or maybe 2x3x8 inch?


you can get 2" OD Velocity Stacks here

http://www.rossmachineracing.com/uni_intakeparts.html

Frank
01-31-2006, 08:27 AM
THAT IS THE SWEETEST SITE EVER!!!!!!!!!!!!!!!!!!!!!!!!!


Frank

SMPerformance
01-31-2006, 08:31 AM
THAT IS THE SWEETEST SITE EVER!!!!!!!!!!!!!!!!!!!!!!!!!


Frank

glad if it can help someone :)

glhs875
01-31-2006, 08:47 AM
you can get 2" OD Velocity Stacks here

http://www.rossmachineracing.com/uni_intakeparts.html

that's the kind of crap I've been looking for, thanks!!!:thumb:

The S is Silent
01-31-2006, 11:22 AM
you can get 2" OD Velocity Stacks here

http://www.rossmachineracing.com/uni_intakeparts.html

That would be $120 to add velocity stacks to an intake manifold. Is that right on par with what CNC machining would cost?

The plenums they sell are pretty sweet. Those would make something like this much easier to do.

johnl
01-31-2006, 02:58 PM
The Ross plenum and stacks would make it pretty simple to build a high volume/big TB right side TB intake with shorter inlet runners based on a chopped off lower half of a two piece, or one piece, 8V intake. Cut the runners until it will fit under an L body hood!

As said by somebody - Short, Fat, and Straight = efficient plumbing.

Taking the intake charge from turbo to intercooler and around to a right side intake means only 360* + or - in directional change, as opposed to the 540* + or - that our typical driver's side inlet requires.

Reduce the turns and increase the diameter.