I remember reading somewhere that the 2g MAS didn't really offer a serious gain on the track. THis is kind of improtant because I need to know fi I should upgrade it, becuase I want to do my intake (get rid of the accordian bullshit), and need to plan ahead as such.
2g MAS, noticeable? nessacery?
sniprfiend
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I remember reading somewhere that the 2g MAS didn't really offer a serious gain on the track. THis is kind of improtant because I need to know fi I should upgrade it, becuase I want to do my intake (get rid of the accordian bullshit), and need to plan ahead as such.
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the 2g flows more than the 1g. you will basically need 550 injectors (some claim they match up perfect with the 2g mas and no fuel adjustments are needed...this is what ive heard), and/or an s-afc. im going to put the one i have sitting here on with my 16g and 550s (one of these years). if you get fuel can help push it back a little. this has been discussed a few times so these should help out.
http://www.dsmtalk.com/forums/showthread.php?threadid=45454&highlight=mas+lean+550s
http://www.dsmtalk.com/forums/showthread.php?threadid=33300&highlight=2g*+MAS
http://www.dsmtalk.com/forums/showthread.php?threadid=4261&highlight=2g*+MAS
http://www.dsmtalk.com/forums/showthread.php?threadid=45454&highlight=mas+lean+550s
http://www.dsmtalk.com/forums/showthread.php?threadid=33300&highlight=2g*+MAS
http://www.dsmtalk.com/forums/showthread.php?threadid=4261&highlight=2g*+MAS
I just upgraded to a Dejontool 3" - 2.5" full intake pipe with 1.5" lower MAS bypass tube. I wanted to stay with the 1G MAS because I didn't want to hassle with the wiring necessary to install the 2G MAS.
I have no proof, but my guess is the Dejontool with lower bypass will flow as much as a 2G MAS.
![Image]()
(this pic is of the full 3" pipe, mine goes from 3" to 2.5")
I have no proof, but my guess is the Dejontool with lower bypass will flow as much as a 2G MAS.
(this pic is of the full 3" pipe, mine goes from 3" to 2.5")
Do you like the Dejon tool intake? I was thinking of going with something similar. I'm guessing that you have an SAFC to account for the increased airflow that is unmeasured. I would like the get the same intake, but I want to make sure they give you a correct "correction" formula.
Yes I do have an S-AFC (the old style with the knobs)
I like the intake very much so far. I've got the bypass capped until I get some bigger injectors and/or I get my faulty EGT probe replaced.
I'm not expecting much of a gain at the dragstrip with the intake alone (although I'm interested to see the difference when I start using the bypass). Throttle response has increased nicely, however.
I like the intake very much so far. I've got the bypass capped until I get some bigger injectors and/or I get my faulty EGT probe replaced.
I'm not expecting much of a gain at the dragstrip with the intake alone (although I'm interested to see the difference when I start using the bypass). Throttle response has increased nicely, however.
A fully hacked 1G MAF will outflow a 2G MAF. However I hear for the 'regular driving experience' that the 2G MAF responds better/quicker. I have a fully hacked 1G MAF on my car and a 2G MAF in the basement. Why? I've so far had no reason to switch.
As I said in another thread I have the base MAF mods with the DejonTool intake (not using the bypass yet) and I see about 2275hz with my 18g and have no overun.
I really like the Dejon piece,looks good and my turbo spools a bit faster than with the crappy accordian pipe.
I really like the Dejon piece,looks good and my turbo spools a bit faster than with the crappy accordian pipe.
I have used 2 1G MAS that overrun at around 2000hz and I dont see any reason why your is not at 2200++hz.
Here is how you check for MAS overrun. Put the S-AFC in graphical mode with Karmen and rpm only. Go for a few run in 3rd gear, look at the graphic of karmen when you reach full boost holding at high rpm. Does it look at a "richter scale" at high rpm? Remember 1st and 2nd is not good to tell since they are too quick. 3rd will show you. Keep us posted.
Here is how you check for MAS overrun. Put the S-AFC in graphical mode with Karmen and rpm only. Go for a few run in 3rd gear, look at the graphic of karmen when you reach full boost holding at high rpm. Does it look at a "richter scale" at high rpm? Remember 1st and 2nd is not good to tell since they are too quick. 3rd will show you. Keep us posted.
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So what does overrunning the MAS actually mean? What are the problems when this happens? what are the signs? because right now on my 1G hacked mass (screw not backed out) im getting between 2000 and 2100 hz. Nothing bad has happened yet... im just want to know what to look for.
Ok,went out and did it and got a very straight solid line,I've been told by fellow DSMers that I got a one of those "special" MASs and am pretty lucky.jw said:
I've also never experienced fuel cut,well ok,once I hit it when the outside temps were in the teens and I was at 17psi.
hmm. I guess you are one of the lucky ones with the *super* 1G MAS or something.
Well, barometric sensor has nothing to do with this because this is MAS overrun and not the other sensors. The signal coming from the karmen vortex itself is missing count. That's why it can be seen on the S-AFC. AFC do not care about your IAT or pressure sensor signal. It's still show overrun. Perhaps this should not be called MAS overrun if you want to be really specific since MAS is MASS air flow but the overrun actually happens on the airflow signal (karmen).
I have another 1G MAS from a friend. I will try that and maybe I'll get lucky this time.
Well, barometric sensor has nothing to do with this because this is MAS overrun and not the other sensors. The signal coming from the karmen vortex itself is missing count. That's why it can be seen on the S-AFC. AFC do not care about your IAT or pressure sensor signal. It's still show overrun. Perhaps this should not be called MAS overrun if you want to be really specific since MAS is MASS air flow but the overrun actually happens on the airflow signal (karmen).
I have another 1G MAS from a friend. I will try that and maybe I'll get lucky this time.
I don't see how a 1g maf can outflow a 2g maf. The 2g maf is 3in and straight through. The 1g has that little hole in the aircan hat. No amount of hacking will overcome that. Along with the size difference, the 2g maf keeps MUCH better count of air. Do you want to fiddle with a hole that lets who knows how much air in or do you want a big maf to count that air and add fuel accordingly. Not to mention the fact that you'll be adjusting the afc to accomidate cold\hot weather. There is no temp sensor for unmetered air. I personally ran a virgin 2g maf (all honeycombs in place) up to 20psi on a T3T4 60-1 without fuel cut. It did help that I had 720cc injectors. I also got 24mpg with this setup. I did the same with my 16g, 550cc, fmic setup and never saw greater than 1600 kharman. I would recommend the 2g maf over a 1g maf ANY day of the week. I don't care if it's a "special" maf or not. More flow means more air.
David
David
ecmoman, what you said we know already. This topic has been discussed before and you do not need to remind us.
I have used 2G MAS for 2 months. The first day I had the MAS in, the car never idle well. I had all kinds of idle surge and stuff but other than that, it works good. I've tried to swap out another 2G MAS from a friend and it's still doing the same thing, so I thought maybe the wiring is the problem and trust me, I check my solder and the harness against VFAQ 10 times and come out to no avail. During cold start, the car would be so lean it doesnt want to idle because of the low trim at around 81% and the O2 trim maxed at 167. It doesnt want to cycle. Therefore on the AFC, I have to rich things by 10% at 1000rpm only. After the car warm up a little, the low trim started to update itself to around 120 because of the leanest. However, after a long drive when the car got hot, it will run so rich with O2 trims around 32 and the fuel trim start to itself back to 81 and stop cycling, I have to adjust the AFC back -10% to overcome the richness. This sucks big time because I have to manually do +10% when the car is cold and then -10% after the car warmed up. Btw, I have done this for 2 months.
Anyway, I kept driving with it because it works good at mid to high throttle without MAS overrun like my 1G does and also got used to the idle problem. It would stall at the light all the time. I turned up the BISS and it work better but I have to idle at 1000rpm
Also, light throttle response sucks big time. I've worked out all my vacuum leaks and boost leak and it still doing the same thing. I finally decided to tried the 1G MAS again after bearing with the 2G MAS for 2 months and voila, the idle surge is gone and the car idle like a champ. Immediately on the first WOT run at 2000hz, I see MAS overrun, added a 1.5" bypass and now, it's seeing around 1800hz without any problem. I have no luck with the 2G MAS and will be saving money for VPC or standalone.
I have used 2G MAS for 2 months. The first day I had the MAS in, the car never idle well. I had all kinds of idle surge and stuff but other than that, it works good. I've tried to swap out another 2G MAS from a friend and it's still doing the same thing, so I thought maybe the wiring is the problem and trust me, I check my solder and the harness against VFAQ 10 times and come out to no avail. During cold start, the car would be so lean it doesnt want to idle because of the low trim at around 81% and the O2 trim maxed at 167. It doesnt want to cycle. Therefore on the AFC, I have to rich things by 10% at 1000rpm only. After the car warm up a little, the low trim started to update itself to around 120 because of the leanest. However, after a long drive when the car got hot, it will run so rich with O2 trims around 32 and the fuel trim start to itself back to 81 and stop cycling, I have to adjust the AFC back -10% to overcome the richness. This sucks big time because I have to manually do +10% when the car is cold and then -10% after the car warmed up. Btw, I have done this for 2 months.
Anyway, I kept driving with it because it works good at mid to high throttle without MAS overrun like my 1G does and also got used to the idle problem. It would stall at the light all the time. I turned up the BISS and it work better but I have to idle at 1000rpm
Also, light throttle response sucks big time. I've worked out all my vacuum leaks and boost leak and it still doing the same thing. I finally decided to tried the 1G MAS again after bearing with the 2G MAS for 2 months and voila, the idle surge is gone and the car idle like a champ. Immediately on the first WOT run at 2000hz, I see MAS overrun, added a 1.5" bypass and now, it's seeing around 1800hz without any problem. I have no luck with the 2G MAS and will be saving money for VPC or standalone.
"I don't see how a 1g maf can outflow a 2g maf."
Let me correct my statement. A fully hacked 1G MAF will flow more air then a 2G MAF without overruning. What good is it if the larger 2G MAF can flow more air but can't count it?
And if you have ever seen my hacked MAF you might reconsider your opinion on which flow more total air.
Let me correct my statement. A fully hacked 1G MAF will flow more air then a 2G MAF without overruning. What good is it if the larger 2G MAF can flow more air but can't count it?
And if you have ever seen my hacked MAF you might reconsider your opinion on which flow more total air.
So what does overrunning the MAS actually mean?
Okay the karman MAFs have a specifically designed chamber. The chamber creates karman vortecies and then counts them. The number of vortecies is directly proportional to the volume of air in the chamber. It takes a minumum amount of volume for the chamber to start working and there is also a maximum wheret he street starts to break down and the vortecies no longer represent the volume accurately.
What MAF overrun is is that the air volume in the metered section is over the maximum the chamber was designed for. The stock DSM would never flow that much air so it wasn't a design concern. The steet breaks down and the number of vortecies starts to drop and get irratic. The MAF is then counting the less vortecies and telling the ECU that's how much vlume is going through. In reality it's far more and so when the ECU supplies fuel for the low value you get a very lean condition.
What are the problems when this happens?
You get very lean condition at the worst time.
what are the signs?
You should see a drop in your a/f accompanied by a drop in the air flow reading on your logger or AFC... but no drop in engine speed!
because right now on my 1G hacked mass (screw not backed out) im getting between 2000 and 2100 hz. Nothing bad has happened yet... im just want to know what to look for.
First off your MAF is not hacked. A hacked MAF is not just removing the lower honeycomb. A fully hacked MAF is removing everything below the metered section.
You should log your car comparing engine speed, air flow and a/f ratio if you are running over 2000 hz just to be safe. Each MAF will overrun at a slightly different value.
Or if you do not have a logger put your AFC on graph like JW says and watch the graph as you do a wot run to reline in 3rd. Watch for any drop or jumps in the airflow not consistant with the rpm.
Okay the karman MAFs have a specifically designed chamber. The chamber creates karman vortecies and then counts them. The number of vortecies is directly proportional to the volume of air in the chamber. It takes a minumum amount of volume for the chamber to start working and there is also a maximum wheret he street starts to break down and the vortecies no longer represent the volume accurately.
What MAF overrun is is that the air volume in the metered section is over the maximum the chamber was designed for. The stock DSM would never flow that much air so it wasn't a design concern. The steet breaks down and the number of vortecies starts to drop and get irratic. The MAF is then counting the less vortecies and telling the ECU that's how much vlume is going through. In reality it's far more and so when the ECU supplies fuel for the low value you get a very lean condition.
What are the problems when this happens?
You get very lean condition at the worst time.
what are the signs?
You should see a drop in your a/f accompanied by a drop in the air flow reading on your logger or AFC... but no drop in engine speed!
because right now on my 1G hacked mass (screw not backed out) im getting between 2000 and 2100 hz. Nothing bad has happened yet... im just want to know what to look for.
First off your MAF is not hacked. A hacked MAF is not just removing the lower honeycomb. A fully hacked MAF is removing everything below the metered section.
You should log your car comparing engine speed, air flow and a/f ratio if you are running over 2000 hz just to be safe. Each MAF will overrun at a slightly different value.
Or if you do not have a logger put your AFC on graph like JW says and watch the graph as you do a wot run to reline in 3rd. Watch for any drop or jumps in the airflow not consistant with the rpm.
"That will definitely delay MAS overrun with the bypass pipe. However, once you start to reach around 2000hz Karmen (even with the bypass), you will still come to the same problem."
I believe Al Blaha is running a fully hacked 1G MAF plus a similar bypass pipe in the 10s now. By fully hacked I mean like mine... nothing below the metered section.
I believe Al Blaha is running a fully hacked 1G MAF plus a similar bypass pipe in the 10s now. By fully hacked I mean like mine... nothing below the metered section.
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