The kd4crs/Power Hungry/Gotts Mod (revisited - and with pictures)

[txarsoncop]

Originally Posted by AgentOrange

Eventually, I want to get rid of the caps and smooth the openings with some type of filler...just haven't figured out what to use yet.

I thought the same thing! I could get my hands inside to all three openings and I thought about taping wax paper to the inside and trying to use the epoxy to seal up the holes...

But then I figured I couldn't match the texture of the intake tube and it would probably need some matrix like a fiberglass cloth or redneck it with screen cloth to help support it; at least while it was drying.

So I got lazy, but I think it's the best possible result w/o doing a LOT of work.

[jimmyv13]

Anyone think it's worth it to use an aftermarket drop in filter with this set up?

[Jackpine]

I entered this post a while back: http://dygytalworld.ehost-services13...12&postcount=2 No one challenged me on it (which doesn't make it true, but it's my feelings on the subject).

I honestly don't see what a "super" filter does for you after 100 miles (except cost more than the OEM brand). Now a cheap knockoff can be a problem - for instance what would happen if the cheap one developed a hole in use?

Again, I'm quite open to having my opinion changed - all I need is a good counter-argument.

- Jack

[txarsoncop]

Ok, for those of us who gleefully cut off our Helmholtz resonators (learn something new every day)...

What do the more learned among you think about this information?

Helmholtz resonators Caution: MUCH geek-speak here!
Although this dumb firefighter was able to get the gist of it.

• They dampen resonance... Duh.
• They make the intake air act "springy" so it fills the combustion chamber more effectively giving us better combustion.

Hmmm, not so sure whipping out that SawZall was such a great idea after all...

Do we need to try to get someone to flow bench or dyno the with and without resonators versions to see if there's a real difference? Seems to me that would be the only answer. Dyno both versions on the same truck and see what the results are.

[jimmyv13]

If they are so beneficial, why don't aftermarket CAI's have them?

[Jackpine]

Bill - I think you're right on the tests needed with and without the resonators. And, don't feel bad about finding that article a difficult read - part of the reason you did is that the guy can't write! He uses words without regard to their meaning so that several sentences are nonsensical. However, I suspect his math is valid for the systems he's studied (which does not match our trucks).

As I said somewhere near the beginning of this thread, fluid flow (air in the duct acts like an fluid) is a very complex, and poorly understood process. I say it's poorly understood because the mathematical models make too many assumptions that allow it to be studied, but that do not allow a precise prediction of the outcome (there's always a bit of error between the predicted results and the actual observed results).

I was concerned about the possible bad effects of turbulence in the duct and it would be very easy I think to create a sort of "standing wave" that would interfere with movement of the air mass into the engine. I would still like to have a smoothly "curved" snorkel section that would turn to match the angle of the intake tube more smoothly than what I have right now. I think the sharp angle I have at the bellows can create problems.

The article seems to say that the resonators act to reduce the effects of turbulence and standing waves.

But, in our case, the resonators were designed for the original duct with the factory snorkel. I honestly have no idea if they are beneficial with the larger intake opening or are actually harmful. However, I felt leaving them on was more prudent than removing them. It also allowed me to return the setup to stock if I chose.

I can only report that the truck seems to run well at WOT and I've noticed no loss in power or adverse effects on gas mileage. Other people seem to say the same for their mods with the resonators removed.

So, the effects of the resonators are probably not enormously significant. (And, sorry if I got "geeky" too)! :o

- Jack

[Jackpine]

Originally Posted by jimmyv13

If they are so beneficial, why don't aftermarket CAI's have them?

Jimmy, your question is good too. My uneducated guess is that the aftermarket CAI manufacturers don't have the engineering brainpower or facilities that Ford has. They take a more "trial and error", "common sense" approach - similar to what we did when we "reasoned" that a wider snorkel would be good.

- Jack

[txarsoncop]

Jack,

Thanks, you confirmed what I thought I was reading.

Granted I understand fluid dynamics are tricky, tricky. So take my musings below with a grain of salt. But, I live next to a PERFECT example of fluid dynamics gone wrong. Plus being a firefighter and having a master plumber for a father I understand the "common sense" wet side pretty well.

The author of the article was referring to a single cylinder engine and, at first, I thought well that's totally wrong for our 8 cyl application. But then I thought I remembered that with a V8 only 2 cylinders are opening at once correct? So it's not really that much different? Except for a convoluted intake path, a filter media and unexplained holes in both the resonators and intake tube.

If I'm remembering correctly I believe you posited somewhere here that the holes might actually be to remove some of the "springyness."


I rounded the edges of my PVC with the Dremel and a file because it just seemed to make sense. Probably didn't make a difference but...