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Speed Density Question

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RocCitySlayer

10+ Year Contributor
792
7
Nov 20, 2011
Rochester, New_York
This is probably a stupid ass question, but im thinking about going with a speed density setup but my question is what exactly does a speed density setup consist of? Any pics would help too.
 
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A MAP(manifold absolute pressure) sensor, IAT(intake air temperature) sensor and a way to control it. It estimates airflow using pressure, temperature, and extrapolates volume to an extent.

As opposed to a MAS system that actually meters the air coming into the engine.
 
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Whats the average cost of a speed density setup? I already have ecmlink v3 but other then that I dont think I have anything else thats needed yet, And what exactly are the benefits of having speed density?
 
Whats the average cost of a speed density setup? I already have ecmlink v3 but other then that I dont think I have anything else thats needed yet, And what exactly are the benefits of having speed density?

GM IAT w/Pigtail is about $30
GM 3bar w/Pigtail is about $80
Decent WBO2 is about $250-$300

Benefits, No MAS. Supposedly easier to tune. Im about to make the jump to SD so I don't have any first hand knowledge of actually tuning with it.
 
GM IAT w/Pigtail is about $30
GM 3bar w/Pigtail is about $80
Decent WBO2 is about $250-$300

Benefits, No MAS. Supposedly easier to tune. Im about to make the jump to SD so I don't have any first hand knowledge of actually tuning with it.

If and when you do go for it please post a thread:thumb: im not 100% sure if im going to go with speed density but it was alittle idea i had. I have been told that I should but im not going to do the tuning myself so that wont be a problem anyway.

This is ECMTuning speed density bundle: ECMTuning, Inc.

Benefits include not having to worry about having a MAS taking up space in the intake tract, boost leaks aren't as big of an issue, if it's your sort of thing, you can properly vent a BOV this way.

Here:

sd101 [ECMTuning - wiki]

Ok cool appreciate the link bro:thumb:
 
To make it as simple as possible, this would be your shopping list to make the switch to SD.
*** You also need to take into account the cost of getting the IAT bung welded into your IC piping and how/where you'll place the MAP sensor. ***

Your question about speed density is very vague, do some research on ECMLink and once you've read everything come back and hopefully you'll have a more specific question.
---> ECMLink Wiki Speed Density Search

I run SD but I don't think its anything to get excited about, honestly. A MAF setup and a SD setup do the same thing, just in a different way. You've already got ECMLink so going to a SD setup wouldn't be hard, you'll just have to determine if its what you want to do or not. I recommend that you learn how to tune your car PROPERLY on the stock 2g MAF setup and then make the switch to SD, if thats something you decide you want to do.

:dsm:
 
A MAF imho is only good for initial dialing in for a sd setup... Then I always remove the MAF and run straight SD. It can be intimidating at first, but just zero out your fuel sliders, make sure to ensure your IAT, MAP etc are all wired correct, and MAKE SURE DSMLINK IS RECOGNIZING THEM, and then just go make numbers higher in cells that you want to be richer, and lower numbers in cells where you want to make her leaner. use the track datalog function. Its a great setup!!! I highly recommend. Just ask questions when your stumped... And once you get it, you get it!
 
To make it as simple as possible, this would be your shopping list to make the switch to SD.
*** You also need to take into account the cost of getting the IAT bung welded into your IC piping and how/where you'll place the MAP sensor. ***

Your question about speed density is very vague, do some research on ECMLink and once you've read everything come back and hopefully you'll have a more specific question.
---> ECMLink Wiki Speed Density Search

I run SD but I don't think its anything to get excited about, honestly. A MAF setup and a SD setup do the same thing, just in a different way. You've already got ECMLink so going to a SD setup wouldn't be hard, you'll just have to determine if its what you want to do or not.

:dsm:

I have about 10 years of welding experience so the welding wouldnt be a problem,:thumb:. And there is already a place for the MAP near the firewall i guess:confused:, The previous owner told me that it used to have a MAP sensor that was taken off, Why? i have no idea but it looks like there is a vacume line and maybe a bracket, And with the tuning aspect I plan on having STM do all my tuning

A MAF imho is only good for initial dialing in for a sd setup... Then I always remove the MAF and run straight SD. It can be intimidating at first, but just zero out your fuel sliders, make sure to ensure your IAT, MAP etc are all wired correct, and MAKE SURE DSMLINK IS RECOGNIZING THEM, and then just go make numbers higher in cells that you want to be richer, and lower numbers in cells where you want to make her leaner. use the track datalog function. Its a great setup!!! I highly recommend. Just ask questions when your stumped... And once you get it, you get it!

Thanks for the advise, I think it is something I am going to put some thought into and I am going to be reading up on it as much as I can
 
Also a major benefit of a SD setup is the MAF/MAS overrun problem with very large turbos. The stock MAS will only go so far before it can no longer meter the incoming air, this is why Ecmlink allows you to either extrapolate the airflow based on a ficticious table, or switch over to a MAP sensor. The GM MAF effectively eliminates this problem, however, above a certain air volume the reading can become unstable and become very troublesome during tuning.
Information from Tom's website about each MAS/MAF and it's capabilities:

maffrequencylimits [ECMTuning - wiki]
 
Also a major benefit of a SD setup is the MAF/MAS overrun problem with very large turbos. The stock MAS will only go so far before it can no longer meter the incoming air, this is why Ecmlink allows you to either extrapolate the airflow based on a ficticious table, or switch over to a MAP sensor. The GM MAF effectively eliminates this problem, however, above a certain air volume the reading can become unstable and become very troublesome during tuning.
Information from Tom's website about each MAS/MAF and it's capabilities:

maffrequencylimits [ECMTuning - wiki]

I have a holset hx35 with a bep .55ar internally gated with a 4" intake.. Should I be conserned about running a stock 2g maf? And i also have an evo 8 maf that came extra with the car when I bought it. What would be the best one to use if I deside NOT to go with the speed density setup? Any ideas?
 
I run SD on my 2g. The omnipower 4-bar MAP is a DIRECT replacement for the stock MDP sensor. screws into the same location, plugs into the factory wiring. And all you have to do is change the input of the factory MDP input in dsmlink. :)
 
I have a holset hx35 with a bep .55ar internally gated with a 4" intake.. Should I be conserned about running a stock 2g maf? And i also have an evo 8 maf that came extra with the car when I bought it. What would be the best one to use if I deside NOT to go with the speed density setup? Any ideas?

You will be fine with either, but I would tune it with the Evo8 MAS since it allows a little more head room incase you decide to upgrade later. You won't have to re-adjust all of your MAS-scaling sliders to adjust for the new MAS. Why do the work twice? Since you're still using a Mitsu MAS, the setup is pretty painless, the GM MAF's can sometimes be a PITA to get setup correctly.
 
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