PRL Cobra Race Maf CAI - Riddle

[Myx]

Here's a 'riddle' for the folks that are in the know.

First, here is a link to the dyno plots of PRLs Cobra CAI vs stock and their Race Maf/Cobra CAI vs stock.
Dyno Plots

Riddle me this........
If the turbo inlet pipe is stock and the end part of PRL's CAI is the same size, then why would enlarging the middle section of the pipe (Race Maf sensor diameter and the PRL tubing from Race maf sensor housing to turbo inlet pipe) enable you to have better low end, midrange and more horsepower/torque up top?

Would making the middle of a straw bigger enable you to drink in more water, faster?


I have a TON more I'd say on this but curious to see what people's take on this would be.

BTW: I have a Cobra CAI and Race maf. I will be getting the race maf calibrated. I plan on personally testing them against each other as well as a 'Myxal' SRI-CAI I plan on making. Just thought this was.....interesting as I've seen no answer as to the WHY this is the case.

For a 'visual' of what I'm talking about, I've uploaded what I've scribbled on a piece of paper. The middle section is the only part that is larger and thus the gains of using a race maf/slightly larger maf-turbo inlet tubing.

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[10GenPearlSi]

You answered the question yourself when you did the straw testing to find out that short straws have better airflow when you suck on them. The race MAF makes the constricted area shorter like a shorter straw. The air inlet is probably very smooth helping laminar flow to make air passage though it easier also. One other thing, the larger MAF would cause slower velocity of the airflow at the MAF sensor at a given RPM. That would cause less turbulence and create greater laminar flow.

 

[Myx]

You answered the question yourself when you did the straw testing to find out that short straws have better airflow when you suck on them. The race MAF makes the constricted area shorter like a shorter straw. The air inlet is probably very smooth helping laminar flow to make air passage though it easier also. One other thing, the larger MAF would cause slower velocity of the airflow at the MAF sensor at a given RPM. That would cause less turbulence and create greater laminar flow.

Thanks for answering and trying to bring clarification this. The PRL race maf housing and tubing is the same length as the non-race maf housing and tubing. The only difference is the PRL race maf is bigger internally and the tubing is bigger where it connects to the maf sensor housing. This made the differences you see in their dyno chart plots. So one is not shorter than the other, just bigger internally. No change before these parts (PRL CAI) and no change after them (turbo inlet pipe).

I've provided some pics below for a visual of what I'm talking about.

 

[10GenPearlSi]

Look at the picture that you drew. The shorter straw is the turbo inlet length which opens into the larger tube and race MAF. The longer straw is shown in your drawing of the stock MAF, tube, plus the turbo inlet. Together they make up the longer straw. I just looked at your drawing.

 

[Myx]

Look at the picture that you drew. The shorter straw is the turbo inlet length which opens into the larger tube and race MAF. The longer straw is shown in your drawing of the stock MAF, tube, plus the turbo inlet. Together they make up the longer straw. I just looked at your drawing.

I see what you mean. My bad! Was just trying to illustrate the section I was talking about.

 

[Ghosted]

Myx,
What's the diameter for the PRL race vs the stock PRL MAF housing?

 

[LilToTo17]

Myx,
What's the diameter for the PRL race vs the stock PRL MAF housing?

50% larger

 

[dallasjhawk]

I see what you mean. My bad! Was just trying to illustrate the section I was talking about.

Wouldn't it just be easier to email them and post the answer or tag them @PRL Motorsports

 

[Myx]

Wouldn't it just be easier to email them and post the answer or tag them @PRL Motorsports

I think the Honda community is smart enough to know why this is or isn't the case. I'm not saying they are lying or anything. However, if you enlarged an intake....any intake, aftermarket or stock...., do you think you'd see gains throughout your powerband and if so, why.

I've done a LOT of dyno testing over the years (Google Myxalplyx Dyno or Kevin Thomas Dyno). Testing little insignificant things to see if any changes took place. I always like to hear people's input on things like this though.

 

[Myx]

Myx,
What's the diameter for the PRL race vs the stock PRL MAF housing?

stock PRL Maf Housing: 61.60mm (2.43")
PRL Race Maf Housing: 74.79mm (2.94")

 

[NarcPatrol]

Here's a 'riddle' for the folks that are in the know.

Would making the middle of a straw bigger enable you to drink in more water, faster?

The limiting factor in this equation would be the capability of the turbo to "drink" the air. The Race MAF has a larger diameter, which increases the total amount of air in the system (as opposed to the stock diameter MAF). This would mean that there is more total air between the intake and the turbo. If the turbo can handle that increased air, then it could potentially provide some gains to the system. I would be interested to see the results of your testing!

Disclaimer: I'm new to tuning/modding cars, so this is just speaking from my aero-engineering background. Could be very wrong

 

[Cscott_xGen]

Where are the dyno graphs from race to street maf?
edit:

https://www.civicx.com/threads/prl-motorsports-street-race-maf-housing-comparison.28371/

 

[Myx]

The limiting factor in this equation would be the capability of the turbo to "drink" the air. The Race MAF has a larger diameter, which increases the total amount of air in the system (as opposed to the stock diameter MAF). This would mean that there is more total air between the intake and the turbo. If the turbo can handle that increased air, then it could potentially provide some gains to the system. I would be interested to see the results of your testing!

Disclaimer: I'm new to tuning/modding cars, so this is just speaking from my aero-engineering background. Could be very wrong

So any widening of the pipe from the turbo forward (Towards the air filter) should generate more horsepower, right? The wider the pipe and the closer it is to the turbo, the more air (More hp) as long as the turbo can handle the increased air, correct?

 

[THATSi]

Let you figure it out but making the comparison to sucking water through a straw is just a bad approach. Water, being a fluid, unlike air, doesn't compress. Just trying to shine some light and let you reach your own conclusions

 

[thatlilwhiteone]

Let you figure it out but making the comparison to sucking water through a straw is just a bad approach. Water, being a fluid, unlike air, doesn't compress. Just trying to shine some light and let you reach your own conclusions

Air is a fluid and water does compress.

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