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Larger Maf Housing


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I apologize - without some background context it's difficult to know whether a poster has looked into what's involved beyond it seeming to be a good idea.

What we need to see are some Dyno pulls on setups still running TD04's, with the larger MAF housing, to substantiate whether it has any merit on a stock hardware setup, rescale or no.

It most likely will be a good idea on any setup. As you know stock setup max's at around 231G/s. After that, load(base injection time to reach lambda 1) is just about maxed as the stock M4.4 maps only go up to 8.02ms, so anything over 8.02 is consider max, even though the true max load is 12.24ms. The equation to calculate load uses MAF signal normalized into kg/hr, rpm and injector constant a few other things. When the MAF is maxed, the only really left modifying load is RPM. Once the system stops seeing an increase in airflow it can no longer calculate the base injection time to reach lambda one, so it starts doing some guessing work along with using the 8.02ms load colum (100%). The good thing about being able to continue measuring how much air mass is entering the engine is the system will know a base injection time, so it will require very little tuning from you.

In the tuners rejoice thread we are almost to the point of using an actually new MAF sensor that can flow up to about 1200kg/hr(333g/s) which can also be scaled up to 1500kg/hr (416g/s) using a larger housing. This can be done my modifying the actualy voltage to air flow map. Imagine being able to flow 55lb/min and still be able to measure the mass of the air coming in. The system will always know where its at.

There is one catch though to increasing flow my replacing your maf or scaling it via the voltage to air flow map. You must also get larger injectors. Larger injectors will actually bring down load (because since they;re larger, they need less time to inject fuel) and stop it from maxing.

Mercuric has determined a Audi S4 2.7T 1200kg/hr maf and green injectors would be a perfect match and would act like stock setup except it can meter up to 333g/s.

Just thought I would share a little info that Mercuric and I have been learning over the past week or two!

Setup looks awesome, im sure Lucky did an awesome job with the tune as usual. Can't wait to see pictures as I want to do a jag can intake as well.

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^ Sounds like you have done some solid work on the MAF issue. When will you be at the point of logging an actual setup? I'm curious to see how it plays out in real world application.

I would like to see TTusb make similar adjustments to the architecture - I would like to know what my flow rate actually is.

Obviously this will all be moot once I switch to VEMS, however optimizing M4.x is more practical for most users.

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^ Sounds like you have done some solid work on the MAF issue. When will you be at the point of logging an actual setup? I'm curious to see how it plays out in real world application.

I would like to see TTusb make similar adjustments to the architecture - I would like to know what my flow rate actually is.

Obviously this will all be moot once I switch to VEMS, however optimizing M4.x is more practical for most users.

Once I get a turbo that flows more.

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