I recently picked up a 3" inlet and outlet MAF housing, I simply replaced my air box with it, and ended it with a standard filtercharger. The car runs like crap with this installed, I went back to stock and it runs fine. Any ideas? please help!!! I got the MAF from www.ATPturbo.com . This is on an 07 Mazdaspeed 3.
Custom short ram not working, help!!!
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problem...shitty intake
solution buy a real one...
solution buy a real one...
i didn't see what you bought and i haven't been following ms3 aftermarket but you just can't change the size of the maf without some tuning to compensate.
are you talking about this?
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if so, the problem is the maf isn't reading the volume of air moving past it.
are you talking about this?
if so, the problem is the maf isn't reading the volume of air moving past it.
There are a bunch of threads explaining why hackjob intakes are likely to fail with our cars. Granted, they are almost all relating to the standard 3, but they all boil down to the fact that the MAFS calculates airflow by sampling the velocity of the intake charge at a specific location. If the curve correlating volumetric airflow to air velocity at that location is not very close to the stock intake (which the MAFS and ECU are calibrated for), then the ECU will be unable to accurately meter fuel, resulting in all sorts of problems. I've personally learned that even the type of entrance to your short ram can be all the difference between a car that runs well and one that barely runs at all.
If I were a betting man, I'd place my money on this being the root of your problem. If you're not sure what I'm talking about, try looking up some of those threads, and especially pay attention to rubyred3's posts on the topic--he's given a lot of good insight and information in this arena!
If I were a betting man, I'd place my money on this being the root of your problem. If you're not sure what I'm talking about, try looking up some of those threads, and especially pay attention to rubyred3's posts on the topic--he's given a lot of good insight and information in this arena!
it's kind of a hybrid thread. it doesn't really have anything to do directly with the turbo so it could go in the mod section but generally, there are more informative/knowledgeable members in this section.
or
it could go in the ms3 section which i never check. segretating the board like that with the "special" vehicle is reason why i dont follow the ms3 aftermarket.
sorry for the rant
or
it could go in the ms3 section which i never check. segretating the board like that with the "special" vehicle is reason why i dont follow the ms3 aftermarket.
sorry for the rant
Ya, I really dont want a CAI, a 2 hp risk over a short ram is not worth it, I live near seattle and we get lots of rain, and big puddles that cannot be avoided. There is currently no short ram available on the market for the MS3, at least that i have seen, have any of you, or is there something else I can do? any help is appreciated.
you can always get a cai and modify it. just leave off the lower half and put the filter there, then turn the pipe a little on the tb, so the filter doesn't hit anything hot, then the filter will be somewhat of a long-short ram intake. you will want to find a way to brace the pipe to the car though, b/c on my cai, the easiest mount is on the lower half, but you can work it out easy enough, also, i know i don't have a ms3, just making a possible suggestion, i think what you bought already was too open, too much free air, not enough resonance...just my opinion.
ya, i think i have the filter element too close to the MAF sensor, I have an old intake from my S2000 that Im gonna cut and make into a custom short ram and get some space between the MAF and the filter. Being that the filter was placed on the end of the adaptor was hopefully the problem. I'll post the results, either way. It should work, being that the CAI has the same MAF opening as mine.
the problem is that the MAF housing is too big, intake velocity is too low, so your MAFS is not sensitive enough to detect changes in airflow accurately. You could probably make this setup work though if you bought one of the reducers (3" to 2.5") that the F2 intake people use, since you've got exactly the same problem they do, that'll probably fix it. I don't really know where to get one of those, maybe send beansoldier a PM.
Alternatively, you could just buy a 2.5" MAF housing and filter instead, but since you've already got the 3" stuff, you probably wanna make it work with what you've bought already, so the reducer is gonna be the cheapest way to do it. All it is is a piece of urethane rubber thats 3" OD and 2.5" ID with a hole cut through it for the MAFS to stick through. This isn't the BEST solution, but then again, a homemade intake solution isn't really the best solution to start with.
Alternatively, you could just buy a 2.5" MAF housing and filter instead, but since you've already got the 3" stuff, you probably wanna make it work with what you've bought already, so the reducer is gonna be the cheapest way to do it. All it is is a piece of urethane rubber thats 3" OD and 2.5" ID with a hole cut through it for the MAFS to stick through. This isn't the BEST solution, but then again, a homemade intake solution isn't really the best solution to start with.
Success!!!! Works great. I cut the 3" intake piping and took it to where the filter is facing down, probably about 5" above where the cai would land me, It looks good and sounds great, It seems to punch a little better when the boost kicks in, but that could just be in my head. My Greddy RS BOV sounds 2x louder , turbo spool can be heard very clearly, and SOTP hp gained 
, and my CPE catback ships out tomorrow!! I'll try to gets pics up today, cant find my firewire/usb cable, its around here somewhere.
, and my CPE catback ships out tomorrow!! I'll try to gets pics up today, cant find my firewire/usb cable, its around here somewhere.Links to pics, please ignore the ghetto zip ties, they're temporary
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I'd get a dyno and check your A/F ratios sometime to be sure that you haven't screwed things up too much. What you've done is this:
Putting the bend in means that most of the air will take the path of least resistance, meaning the outside of the bend (which is the part of the flow sampled by the MAF) will carry most of the flow. This is how what you have done has brought the intake velocity up sufficiently for the MAF to read it.
This means that you have changed the SHAPE of the velocity profile of the flow that goes past the MAF, in addition to adjusting the magnitude by using the larger housing. If the velocity profile changes, the MAF transfer function will need to be adjusted.
The dynamic trim adjustment based on the o2 sensor in our car can compensate for changes in magnitude, but not for changes in shape, so I worry that you might have thrown some of the A/F ratios off by doing this.
This of course, assumes that the stock intake was straight, which it may not have been, I know in the regular 3, the intake had a bend in it right before the MAF as well, so you may have simply been returning the velocity profile back to its original shape, check your stock intake, and see if there is a similar bend right before the MAF (I don't have a speed 3, so I can't speak to this).
You're probably fine. As others will tell you, I'm a paranoid freak when it comes to my car, as long as it appears to be running fine, you should be ok, just make sure it doesn't go lean at all at higher rpms+load, b/c that will cause detonation, which is a very bad thing, especially on a turbo car.
Putting the bend in means that most of the air will take the path of least resistance, meaning the outside of the bend (which is the part of the flow sampled by the MAF) will carry most of the flow. This is how what you have done has brought the intake velocity up sufficiently for the MAF to read it.
This means that you have changed the SHAPE of the velocity profile of the flow that goes past the MAF, in addition to adjusting the magnitude by using the larger housing. If the velocity profile changes, the MAF transfer function will need to be adjusted.
The dynamic trim adjustment based on the o2 sensor in our car can compensate for changes in magnitude, but not for changes in shape, so I worry that you might have thrown some of the A/F ratios off by doing this.
This of course, assumes that the stock intake was straight, which it may not have been, I know in the regular 3, the intake had a bend in it right before the MAF as well, so you may have simply been returning the velocity profile back to its original shape, check your stock intake, and see if there is a similar bend right before the MAF (I don't have a speed 3, so I can't speak to this).
You're probably fine. As others will tell you, I'm a paranoid freak when it comes to my car, as long as it appears to be running fine, you should be ok, just make sure it doesn't go lean at all at higher rpms+load, b/c that will cause detonation, which is a very bad thing, especially on a turbo car.
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I also had a simular problem when using one of those air flow sensor pipes and a filter attached to the end. Caused the car to have an unstable idle - reverted to stock, no problems. Only took that route because I got the parts cheap through work. I'll look at getting a 3 specific kit in the near future.
[quote author=GT1 link=topic=73148.msg1302767#msg1302767 date=1175321885]
Do you have access to an OBD scanner that can read long term fuel trims?
If so, you can verify what rubyred3 mentioned in his previous post (changing the shape of the velocity profile).
[/quote]
no, you won't be able to verify this with a can tool. It would be a useful diagnostic (if your long term fuel trim is rather high, you might want to look into some sort of a tuning solution as this is an indication that you have screwed up the fuel tuning), but won't tell you if you are running dangerously lean at some points, as the accuracy of the narrow band lambda (o2) sensor is very limited.
Do you have access to an OBD scanner that can read long term fuel trims?
If so, you can verify what rubyred3 mentioned in his previous post (changing the shape of the velocity profile).
[/quote]
no, you won't be able to verify this with a can tool. It would be a useful diagnostic (if your long term fuel trim is rather high, you might want to look into some sort of a tuning solution as this is an indication that you have screwed up the fuel tuning), but won't tell you if you are running dangerously lean at some points, as the accuracy of the narrow band lambda (o2) sensor is very limited.
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