mark kibort

turbulence = pressure drop= bad.

the only time a "swirl" will help, is around tight turns, like the effect of inlet guide vanes, but internal to the air path.

mk

Mike Frye

I'm working on a crazy idea about a bundle of smaller tubes, rather than one open one. The cross section would be like a bunch of straws bundled together. This would ensure (I think) the laminar flow without causing eddies in the air current and hopefully allow the air to move straight around the bends and into the intake. -copyright- TM- all rights reserved- 2007 Mike Frye

Anyone know why this wouldn't work?

JEC_31

True, true. I was thinking about combustion chambers and velocity.





I'm going to take a stab and say that the bundle-of-straws would multiply by a huge factor the amount of wall-friction, and that a bend in a little straw is the same as a bend in a big straw to the air molecules.

But hey - prove me wrong! (which is usually not difficult, lawlz)

heinrich

It's all about air speed, RAM effect, turbulence and especially resonance. Intake plenum side plate spacers add resonance space, which does not add hp, just shifts resonant powermaking peaks higher or lower. Why the Blackbird makes power, I cannot say, because every other such design has failed dismally. Maybe it makes turbulence in just the right way.

heinrich

Not according to Louis Ott ... turbulence is important in some ways to help the air get where it needs to. You always have turbulence inside a tube/tubes that bend and change air path. The question is managing that turbulence, and creating good turbulence. Without turbulence over and under your car Mark, you would be flying high

heinrich

Oh yes another good kind of turbulence is the kind that mists fuel vapours.

Fabio421

Maybe by moving the filters further away from the engine, the air is allowed to smooth out again before entering the engine.

Or maybe there aren't any true gains. Time will tell.

sweanders

I fail to see what is actually changed with the intake on the the car with the Blackbird setup? I can see the difference in airbox and filters but not much more?

Louie showed me some of the design features with the stock airbox and it is much more complex than just being a box to hold the filter in place with.

MGW-Fla

hmmmmm..... now that sounds like a cost effective mod that I could afford!

Ed MD

Mark, your absolutly right about the variables. Also the 5% should be 5HP. I'm embarrassed about this screw up, as my day job requires me to present data and findings objectively and accurately. I'm also "posting challenge". I've tried to download all the dyno sheets but can't. Here's a summary of the outcomes in SAE:

w/o BB/Feb
-HP- -TQ-
284.3 303.6
282.4 300.0
These were the last two runs, without changing the AFR.
(The first one before AFR adjustments was: 278.9/286.8.)

w/BB/Jun
-HP- -TQ-
294.8 313.6
290.4 308.5
293.8 316.8
XXXX XXXX
292.6 315.2
(the fourth run was not complete, only done to see if the "blip" at 5000 rpm was artifact or real)

Again here's the data off the sheets, and my apologies.
Regardless, it does look awesome.
Ed M

MGW-Fla

Yeah, it does look really sharp compared to the stock cheapie looking tubes. The stock tubes just don't have the same quality look with the overall hand built craftmanship of the rest of the car. Especially with the wear of 12-29 years. DR's new tubes make your shark surely look faster! Whether it really is or isn't 5hp more, doesn't really matter to me!

Ed MD

Thanks Mel, Ed

inactiveuser1228

Anders,

From what I understand of intake design, not much and all learned from work done by others in the 60s on drag racing engines. The longer and smoother the run before the intake valve, the more even and smooth ( as far as pressure) the charge going into the cylinder. Kind of like how a siphon in a hose works, when a certain volume of water exits the hose, an equal volume replaces it partly because of the vacume/suction, but also because of the volicty of the column of water. If the engine is sucking its air from a large open area (i.e. the stock air box) the column or air moving through the MAF has to stop and start and stop and start in an erratic way. If however, like it seems here, you have a long smooth run after the filters, the air achieves a nice smooth velocity before entering the cylinders that is effected very little by the sudden opening and closing of the intake valves. Just my .02.

sweanders

Uhm, no. The stock intake isn't changed. Just the parts outside of it like air filter box and connecting pipes.

It looks like a cool air filter box replacement, but it still uses the stock intake.

inactiveuser1228

Anders,

Are we not talking about the Blackbird design?

Steve