Engine Difference Between Maf For Stock Airbox Vs Fenderwell Cai

Discussion in 'Fox 5.0 Mustang Tech' started by JasinC19, May 31, 2013.

  1. JasinC19

    JasinC19 What hole is this!?!

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    I was wondering what the real difference between a MAF for the stock airbox vs a fenderwell CAI is.

    Example is PRO-M's units. Why is one better suited for a CAI?

    Also, is anyone running a 75mm PRO-M for 24# injectors with a BBK CAI?
    Product Here

    Thanks
    J
     
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  2. Bill Gordon

    Bill Gordon Active Member

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    I am running a Pro M 75mm MAF calibrated for 42# injectors and CAI. The CAI is a BBK. The setup runs awesome with the blower. After talking to Pro M, they said the CAI tuned MAF is calibrated for the 90* elbow in the CAI, the elbow creates turbulence in the airflow, which can upset a non CAI calibrated MAF. The stock airbox is a plenum which allows the airflow to settle out before it hits the MAF. Hope this helps.
     
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  3. JasinC19

    JasinC19 What hole is this!?!

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    Thanks Bill. I talked to c&l and they claim that the maf I have is correct and fine for stock box and bbk cai and that it takes just 6 inches of straight pipe before maf to straighten out the air flow. Not sure how true that is... Or if the bbk even qualifies.

    I'll probably break down and switch to pro m eventually to eliminate another possibility...

     
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  4. Rick 91GT

    SN Certified Technician Site Sponsor

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    Correct.... Lee @ C&L is a smart guy

    Sent from my XT907 using Tapatalk 2
     
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  5. JasinC19

    JasinC19 What hole is this!?!

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    Update: I got the Pro-M MAF installed. I could be wrong, but it definitely seemed to help a bit. Still pretty rough.

    Tonight I took the upper intake off, rerouted the PCV hose from the side of the intake back to underneath the manifold.

    Then I retorqued the lower intake bolts 5 or 6 times. They were't loose per se, but they were defintely out of spec.

    I turned the key and.......

    It drives a lot better! :D :D :D :D :D :D :D :D

    I ripped it around my neighborhood dodging small children, pets, and geriatrics and it is actually quite driveable!

    I don't want to jinx myself but I think I solved a lot of my issue tonight!

    Thanks for everyone's help. Once I get it straightened out and inspected I'll take a video and post it so you guys can check her out.

    Jason
     
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  6. Rick 91GT

    SN Certified Technician Site Sponsor

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    Based on that video you sent... I am 99% sure you had a vac leak

    Sent from my XT907 using Tapatalk 2
     
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  7. JasinC19

    JasinC19 What hole is this!?!

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    Hmm well there were a few vac line nipples capped off with some caps that were dried up that I replaced. That could've been something...

    If the lower intake were loose, could that have been sucking air?
     
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  8. Rick 91GT

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    Yup....I also like to nylon wire tie those caps and all vac lines

    Sent from my XT907 using Tapatalk 2
     
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  9. 306N/A

    306N/A Member

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    I am running a 75 mm bbk maf 24lb with a bbk cai ran like **** for a few hours, but corrected itself now runs flawless :)
     
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  10. 7991LXnSHO

    7991LXnSHO Well-Known Member

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    Hate it when that happens. EFI is picky about that. Glad you are up and running.
     
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  11. 306N/A

    306N/A Member

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    Now it runs like garbage again??? computer not remembering the new fuel air curve ???
     
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