Speed Density

jessetooslow

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May 11, 2007
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Ok, help me out here, I have heard of guys switching over to the Speed Density way, why would that be better, I was a ford guy before, I was always told mass air is better for modifying the car to run better, am I missing out on something?
 

Nick M

Black Rifles Matter
Sep 9, 2005
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jessetooslow;1024839 said:
Ok, help me out here, I have heard of guys switching over to the Speed Density way, why would that be better, I was a ford guy before, I was always told mass air is better for modifying the car to run better, am I missing out on something?

You were told correct. Keep in mind, we don't have mass air. For example, the Karman Vortex has no way to account for humidity. The hot wire does.

Speed density requires changes when you make changes. What is good is the MAFT-Pro system devolped for us is user friendly and is adaptable. It allows you to go beyond factory fuel cut, and tune for higher horsepower. That is its tremendous advantage over stock. And it is a really good price.

Nice article JJ. And they say old gear heads don't know anything. :biglaugh:
 

Doward

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Jan 11, 2006
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Nick M;1025457 said:
You were told correct. Keep in mind, we don't have mass air. For example, the Karman Vortex has no way to account for humidity. The hot wire does.

Speed density requires changes when you make changes. What is good is the MAFT-Pro system devolped for us is user friendly and is adaptable. It allows you to go beyond factory fuel cut, and tune for higher horsepower. That is its tremendous advantage over stock. And it is a really good price.

Nice article JJ. And they say old gear heads don't know anything. :biglaugh:

LOL.

Were you told correct? It depends on whom you speak with. I prefer Speed Density over MAF based systems, specifically for turbocharged applications.

I use MAF based systems for NA applications. My biggest beef(s) with MAF systems are a) you are limited to whatever the maximum frequency (or voltage, though IMHO, the frequency based MAFs are superior due to resolution) the device outputs, and b) zero way to compensate for pressure differences. The MAF measures mass, not pressure.

Honestly, I've seen some seriously passionate debates over this. IMHO, the single best system I've used to date, is GM's dual MAF/MAP OBDII system. Combine both and you get top notch fueling under any condition.

BTW, the bigger MAF + bigger injectors used in Ford applications is exactly the same as the lex/550s. And yes, you skew the timing table there, too, unless you reprogram.
 

figgie

Supramania Contributor
Mar 30, 2005
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Doward

Preference does not make it better ;)

On the technical front, Mass Air Flow is always SUPERIOR as you are taking a DIRECT measurement of the incoming air. No interpolation needed as with Speed denisty. But of course then comes the part of creating a MAF to fuel look up table and that is never easy if it has never been done.
 

gixxer750

2jzget comingsoon!
Mar 30, 2005
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I've got an aem for sale that will let you go speed density, maf, or keep the kv afm...

click sig... and I prefer speed density too.
 

WhtMa71

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Apr 24, 2007
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I plan to go speed density in the future..Another good thing about it is if you blow an IC pipe off you can still actually drive your car home.
 

Nick M

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Sep 9, 2005
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figgie;1025568 said:
Doward

Preference does not make it better ;)

On the technical front, Mass Air Flow is always SUPERIOR as you are taking a DIRECT measurement of the incoming air. No interpolation needed as with Speed denisty. But of course then comes the part of creating a MAF to fuel look up table and that is never easy if it has never been done.

Yep. It isn't my "prefrence".


http://video.google.com/videoplay?docid=-2408738952289885249&hl=en

Mass air flow system at its best.