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MAF vs Speed Density

charmcity

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Oct 19, 2007
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283
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baltimore
OK guys ive been reading around about the pro's of Speed density and im just wondering if it is a good/better upgrade to the maft set-ups being run. I have a MAF-T and gm maf but my car is not running yet so i could make a change if need be. I am also looking into the ostrich emulator instead of the DSMLINK just want to know what the VR4 expers think.


Again thanks in advance
 

jepherz

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I use the ostrich and plan to keep my 3g maf as long as it works. With a maf you don't have to retune for every mod to take advantage of it.
 

charmcity

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Oct 19, 2007
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283
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baltimore
How is the ostrich as far as tunning goes, and have you had any experience with DSMLINK. If so compare and contrast.
 

You don't tune with the ostrich, it is an EPROM Chip Emulator.
Realtime binanary up/downloading.

www.ds-map.net

IMO, DSMLink is like coloring with crayons and stencils, and the bin editing programs such as this one, are like oil paintings.

They both provide color, but there's only so much you can do with crayons...
 

charmcity

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283
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Well damnit now im confused, what exactly is the ds-map stuff, I didnt see a product or anybody talking about it. just software and dsm down talk. please someone break it down. Im not a dummy but I feel like one.
 

turbowop

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Yakima, WA
Quoting number638:


IMO, DSMLink is like coloring with crayons and stencils, and the bin editing programs such as this one, are like oil paintings.

They both provide color, but there's only so much you can do with crayons...




Crayons in the right hands can look way better than oil paint in the wrong ones. /ubbthreads/images/graemlins/hsugh.gif
 

DarkDevilMMM

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4,065
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Vacaville, CA
first, no need to start a pissing war between the two choices, it's all about preference.

To each of its own, if you have baller money and don't want the headache of learning the basic about ECU, a bit of assembly, and a bit DIY formatting, wants to just plug and play and don't care about the extra features that you can actually do with your stock ECU, then go for DSMlink.

If you are a bit adventurous, wanna go as cheap as possible because you don't mind the DIY BS, also want to learn more about how the ECU actually works and like to tailor stuff to your own taste with some researching, then go for ostrich.

End result is very similar, just different paths that you can take to get you there. DSMLink is limited to what their software let you do, but it's more then enough for most users. Ostrich can do the same and then some, but most people can't unleash the real power of it without a bit of headache, research and a bit of electronic/computer skills. That is what Jeff means by crayon paintings and oil paintings. I haven't really heard anybody who have used Ostrich wasn't impressed by it, same goes for DSMlink, it's down to your own personality.


Second, thread title state MAF vs Speed Density, so how come your discussion seems like to be focusing on DSMLink vs Ostrich?? 'MAFT vs SD' and 'Link vs Ostrich' are two totally different things, so what are you trying to do? I would suggest do a bit research first, then ask more specific questions.
 

cheekychimp

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East Sussex, U.K.
I remember talking to Mark (Turbowop) before and he told me that he thought the DSM/GVR4 type MAF was definitely a restriction in the intake. I can't really say yay or nay to this but I would say that for the most part the issue with a MAF generally is NOT that it can't flow enough air, but that when airflow exceeds a certain point (the 'overrun' point) the MAF simply cannot keep up and measure the air fast enough. Ultimately this means the ECU doesn't get accurate enough information to allow it to make the correct air/fuel ratio calibrations and performance suffers or you get 'breaking up'.

DSMLink gets around this issue by using a very crude VE table that bypasses the MAF and puts the ECU into speed density mode at wide open throttle only. It works well for what it is and provides a workaround to the problem of overrun, while allowing users to keep the MAF and to have the vehicle drive essentially like stock at part throttle.

Now to run a vehicle in speed density mode all the time requires a far more sophisticated VE table that is capable of keeping the car running smoothly at part throttle and idle. Setting up a standalone to run speed density permanently can therefore be more tricky and often requires further tuning whenever you change your setup/turbo. However, before anyone starts telling you that speed density causes loss of driveability, remember Honda doesn't use MAFs in it's engines, and my Civic Type R is one of the smoothest cars I've ever driven.

There are advantages and disadvantages to both speed density and MAF based setups, just as there are advantages and disadvantages to both DSMLink and Ostrich. I can relate to the crayons and oil paintings analogy above, but I think of it more along the lines of buying a camera. If you buy a decent, compact point and shoot camera and set it to 'Auto', you'll most likely get decent usable photos from it in most situations. There will always be limits to the results you can achieve and ultimately a skilled photographer with a top of the range manual SLR camera and a case of lenses will produce far better pictures. BUT you can also be sure that if the unskilled user doesn't know what he is doing or how to handle the settings properly, he will probably get worse results using that top of the range camera than with the point and shoot one.
 

charmcity

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Oct 19, 2007
Messages
283
Location
baltimore
Ok well I guess my original question was not right. I did not understand the difference in speed density vs MAFT. I bought a 3in GM maf and translator and had planned on running DSMLINK, but now im reading about ostrich and hearing about speed density and figured they were one in the same. I guess my question is what are the parts/ mods needed to run our cars speed density. Im sorry I just could not find a definate answer in the threads ive read. Thanks
 

G

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zompton
Go aem ems/ speed density you won't be sorry.
 

jepherz

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Aug 8, 2004
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KC, Missouri
I think you need to clarify what you're trying to achieve. Asking what the difference between speed density and the ostrich is like asking what the difference between apples and oranges is.

Speed density or map, is a method of measuring the amount of air flowing into your engine. It can be achieved with DS-map, which I believe uses the stock ecu with new code. Else, you can use something like Maft Pro. In either case, you're just replacing the MAF in your car with another device to provide the ECU with a maf input.

The ostrich is simply an eprom emulator. Anything that you can burn to a new eprom and slap in your ecu is accomplished just the same with the ostrich. You should also be able to accomplish any tuning that DSMLINK can, with more work.

All in all, the GM maf and translator is much older, outdated technology and you're better off going with something else. I personally use a 3g maf with the Ostrich and don't have any complaints.
 
Last edited:

Gimpin

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Joined
Jun 9, 2007
Messages
557
Location
Plant City, FL
Quoting charmcity:
Ok well I guess my original question was not right. I did not understand the difference in speed density vs MAFT. I bought a 3in GM maf and translator and had planned on running DSMLINK, but now im reading about ostrich and hearing about speed density and figured they were one in the same. I guess my question is what are the parts/ mods needed to run our cars speed density. Im sorry I just could not find a definate answer in the threads ive read. Thanks




to convert to speed density you need
1. GM 3 bar map
2. GM Intake air temp sensor
3. Eprom ECU
4. Ostrich to tune with
5. DS-Map software (www.ds-map.com)
 

jepherz

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Aug 8, 2004
Messages
7,877
Location
KC, Missouri
Quoting G:
Go aem ems/ speed density you won't be sorry.



I don't think that's really helping answer his questions.
 

Rausch

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Dec 21, 2004
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12,049
Location
Cleveland, OH
I think you should restate your questions more with the goals you have in mind. For example, You want to make x amount of power that will be driven at the track only/daily, etc. Key points that will clue others in to what it is you are trying to accomplish. "I want to vent my BOV to atmosphere." would also qualify, but Is not worth the $$ involved to do so without any other goals.

Some helpful info, maybe:
1. As stated the Ostrich allows you to 'burn' or code a chip to install into the ECU.
The Above mentioned DS tuning software allows you to open the related maps or tables to make finite adjustments to things like injector pulse width/duty cycle, timing maps, airflow adjustments, etc. to build a 'tune' to burn onto a chip. The DS-MAps primary feature is that it's based around using a MAP sensor as opposed to a MAS (1g, 2g, 3g). More or less.

This is in many ways similar to a standalone ECU, such as the AEM or Megasquirt ECU, but the AEM EMS and even the Megasquirt offer more options than the basics. If you intend to go this route, consider the megasquirt as a middle ground between the DS and Ostrich, and the AEM. It offers some other features, such as the ability to run in Speed density alone, that can make it a good choice on a budget. All in all, you should know what you are doing before going this route, as you are effectively building you own 'tune' from scratch, essentially. A lot can go wrong if you are not aware of what you are adjusting, and how it will effect your setup. If you are not careful and educated to the task at hand, you can get lost fairly easily.

2. DSMlink is more straightforward than the above, but still requires you to build your own tune. There is a ton of support for this particular avenue, so it may be easier to set up and adjust than the above. DSMlink does have a Speed density function, but it does still require you to run a MAS. It's use is to compensate in instances where you would over-run the Mass air sensor. V2 is set up with that option. I don't know if V3 will have provisions for speed density alone, but someone in the know may have more info.

3. Get onto Keydivers site, DSMChips , and order a chip, injectors, etc, and have him burn the chip to your specs. In this case 95% of the 'tuning' is already done, and you can go in and make smaller adjustments with the FPR and SAFC to maximize the set up. A logger is a must with this set up.

There are other options, but it really comes down to your skill level and goals. Plenty of people have gone though the effort to learn and understand how to tune their vehicles with any of the above mentioned options, and plenty of others (VPC, Haltech, Etc.) on many different levels. /ubbthreads/images/graemlins/grin.gif
 

atc250r

Staff member
Joined
Sep 11, 2003
Messages
13,235
Location
Orange County, NY
Don't forget the old school option, HKS-VPC. I have had mine for a few years, the car runs very well, its street manners are excellent, and if I didn't tell you I was running it you wouldn't notice just by cruising around town. However, without Jeff's chip in the ECU mine wouldn't run as well as it does. On the other side of the coin, a properly set up 2G/3G/Evo MAS is an excellent set up that plenty of people have gone really fast on. I have tried working with a GM MAFT on another members car (I had it for a few weeks while I was doing a bunch of work on it) and I didn't like it. Every time I'd get it tuned pretty well the weather would change and the tune would go out the window. Plus I'm not a big fan of blowing hot, oily, compressed air through a MAF that was never designed to be used in that fashion. Again, a lot of people have had good experiences with that setup as well but that was not my experience. If you want simplicity and driveability in a reasonably inexpensive package then a KD chipped stock ECU with a 2G,3G, or Evo MAS is probably the way to go. If you're looking to make maximum power then going to speed density will probably be your best bet.

John
 

Andy_S

Well-known member
Joined
Jan 30, 2007
Messages
982
Location
Shithole Wisconsin
Quoting VRausch4:
I think you should restate your questions more with the goals you have in mind. For example, You want to make x amount of power that will be driven at the track only/daily, etc. Key points that will clue others in to what it is you are trying to accomplish. "I want to vent my BOV to atmosphere." would also qualify, but Is not worth the $$ involved to do so without any other goals.

Some helpful info, maybe:
1. As stated the Ostrich allows you to 'burn' or code a chip to install into the ECU.
The Above mentioned DS tuning software allows you to open the related maps or tables to make finite adjustments to things like injector pulse width/duty cycle, timing maps, airflow adjustments, etc. to build a 'tune' to burn onto a chip. The DS-MAps primary feature is that it's based around using a MAP sensor as opposed to a MAS (1g, 2g, 3g). More or less.

This is in many ways similar to a standalone ECU, such as the AEM or Megasquirt ECU, but the AEM EMS and even the Megasquirt offer more options than the basics. If you intend to go this route, consider the megasquirt as a middle ground between the DS and Ostrich, and the AEM. It offers some other features, such as the ability to run in Speed density alone, that can make it a good choice on a budget. All in all, you should know what you are doing before going this route, as you are effectively building you own 'tune' from scratch, essentially. A lot can go wrong if you are not aware of what you are adjusting, and how it will effect your setup. If you are not careful and educated to the task at hand, you can get lost fairly easily.

2. DSMlink is more straightforward than the above, but still requires you to build your own tune. There is a ton of support for this particular avenue, so it may be easier to set up and adjust than the above. DSMlink does have a Speed density function, but it does still require you to run a MAS. It's use is to compensate in instances where you would over-run the Mass air sensor. V2 is set up with that option. I don't know if V3 will have provisions for speed density alone, but someone in the know may have more info.

3. Get onto Keydivers site, DSMChips , and order a chip, injectors, etc, and have him burn the chip to your specs. In this case 95% of the 'tuning' is already done, and you can go in and make smaller adjustments with the FPR and SAFC to maximize the set up. A logger is a must with this set up.

There are other options, but it really comes down to your skill level and goals. Plenty of people have gone though the effort to learn and understand how to tune their vehicles with any of the above mentioned options, and plenty of others (VPC, Haltech, Etc.) on many different levels. /ubbthreads/images/graemlins/grin.gif



Good post. Lots of good info there. Have you had any experience with megasquirt. I am in the process of choosing a tuning setup and am curious on megaquirt. Price is right and you get to use MAP.
 

charmcity

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Joined
Oct 19, 2007
Messages
283
Location
baltimore
Thanks guys alot of great information I have some research to do but I love to learn this stuff more and more. My goal is 400whp/tq on the street DD but to dyno and see what my set-up will take.

weiseco pistons 9:1
Manley rods
ARP head/mains
HKS 272's
manley valves
1000cc inj
255 walboro
FPR
ACT 2600
front mount
HX-40 Snail

And I want to make reliable power thats ok to drive on and the ocational 1320 trip but I just want to have the right tools to do well. I do want to vent to the air and I dont mind learning I just want to have whats best for my set up.
 

curtis

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Joined
May 4, 2003
Messages
11,892
Location
Clarksville TN
Not sure about all of these except the pro....I have a new one awaiting install when I get the car together, I have a lot of local friends that have them and they work.

You put in a wideband and tell the maft pro to read it above a certain rpm and you set your own air fuel ratio. Below it reads off the stock o2, above that rpm it reads from the wideband and samples like 128 times a second, if you turn up the boost it adjusts, spray meth it adjusts, spray nitrous oxide yep you got it adjusts.

Start the car when cold no idle problems, slam the brakes at an intersection it idles, big cams it idles no searching around trying to run, the best part is from off throttle to wot it goes no stuttering , popping etc. Drives like a new car from the showroom.

I have a friend with translator pro on a 35r powered evo, 272's with gears, 3 inch exhaust, big front mount, injectors, regulator, pump, spraying meth with good rods and pistons and a exedy dual disk clutch. At the time with these mods the car only ran mid 11's with serious tire spin but the car ran 134mph....Thats fast, with traction and a good sixty foot its a 10 second car but it drives and acts like a new car with no mods.
 

Rausch

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Joined
Dec 21, 2004
Messages
12,049
Location
Cleveland, OH
/ubbthreads/images/graemlins/banghead.gif I started typing and totally forgot to include the MAFT-Pro. I bought one when it first came out, never installed it, and wound up selling it off to fund other things. I have played with a couple, albeit briefly, and noticed that there are a whole lot of controls and functions, more than I expected. Very cool alternative as well for running MAP/Speed Density.

There are a few guys running these (*cough* Turbowop) /ubbthreads/images/graemlins/grin.gif that can tell you more about what's already been said.

Quote:
Have you had any experience with megasquirt.

Not really. Cruised through the layout and software briefly, and have done some reading, but again, there are members here that have experience with this one as well...(*cough* Chris) /ubbthreads/images/graemlins/grin.gif

/Seems to have a cough/ /ubbthreads/images/graemlins/tongue.gif
 
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