Blow through maf and other questions

  • #1

    Blow through maf and other questions

    so as of right now i have a 85 vg30et engine ( rebuilt and bored 20 over) in my 87 na, car is daily driven when i get it running again
    setup:
    hx35w with pw39 external wastegate (relocation pipe)
    2.5” intercooler piping
    greddy rs bov
    tomei fpr
    450cc dsm injectors
    nistune
    currently running on 12psi

    I heard it’s best to run a blow through set up especially with a bov, what do i need to do this ?
    Is there anything else that needs to be done for the car to be able to start and run (minus tune) ?
    do i even need to run blow through ?
    Whats the best maf to use for blow though? Cobra , z32

    sorry for all the questions just trying to get my car boosted
    any advice would help
    Looking for 300-350hp
    Last edited by Coffeygr; 02-21-2018, 11:20 PM.
    Tags: blow through, hx35, maf, nistune, z31
  • #2
    I've been doing a lot of research on this myself. Here's a good tech article that will probably answer most of your questions:

    http://www.lasotaracing.com/techdrawthroug.html

    I'll defer to the more "learned" among us for maf selection, but for a blow through application, I'm personally leaning towards the ford '05 slot type MAF.

    The main difference that you will see is the draw through MAF will have a bit of lag in the readings when you close the throttle, causing a temporary rich condition. Also, the draw through setup must have the BOV recirculated or you will get false readings when it's open.
    Last edited by mwolvinm; 02-26-2018, 12:51 PM. Reason: editing hyperlink-- Thanks Dunkine for bringing it up!
    --------------
    Legal stuff:
    **Nissan Employee**
    Any information shared is simply my own opinion and NOT the opinion of Nissan

    not legal stuff:
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    '22 Q60RS-- I tell the wife it's hers…
    '87 Chaparral bowrider-- the next project
    '00 Corolla-- kids car.
    '14 E-350-- Gotta haul those kids in something.

    Comment

  • #3
    Covered on here back in 2012 too:
    https://z31performance.com/forum/z31…aw-through-maf

    Comment

    • Coffeygr
      #3.1
      Coffeygr commented
      02-24-2018, 06:05 PM
      I’ve read that topic many times, I’ve read a lot of things but they are all based on 2012 and back, and it’s still unclear of what’s best to use and i wanted to see if there was any better responses dew to it being 2018 now
    • Dunkine
      #3.2
      Dunkine commented
      02-25-2018, 10:47 AM
      If you are going to daily drive it, I don't think you will have issues either way. If you have everything to run it draw through, do that and if you want to blow through later, gather the parts and switch it over. Then post the differences between the two or lack thereof
    • Coffeygr
      #3.3
      Coffeygr commented
      02-25-2018, 07:03 PM
      Alright that sounds reasonable and it’d help the forums out
  • #4
    Could you run an aftermarket bypass valve instead of the BOV?

    Comment

    • Coffeygr
      #4.1
      Coffeygr commented
      02-25-2018, 07:04 PM
      I was just going to run the bov back into the intake to solve the problem, i wouldn’t even run a bov if i wasn’t a stupid college student and bought it cause “i though it’s was cool”
    • Dunkine
      #4.2
      Dunkine commented
      02-25-2018, 08:32 PM
      The sound is pretty cool
  • #5
    I run an HPX N2 MAF in blow through configuration, BOV on the hotside going into the IC. The MAF is housed in a 3" tube with air straightener. I run Nistune with feature pack installed. Zero issues. 1000cc injectors at 43.5psi
    Last edited by Augustus Maximus; 03-11-2018, 12:50 AM.
    Cha iro

    enjoy building it yourself.
    if it fails, fuck it.
    at least you gave it a whirl.
  • #6
    I run drawthru on a stock MAF. Making over 500RWHP and 500RWTQ for over 4 years now on a stock engine with NISTune. Car runs great but when shifting under WOT there is a small blip rich condition before you hammer down into the next gear. This attributed to the BOV like mentioned. Other than that I'm very happy with how it runs considering in using the stock MAF, stock Distributor, stock ign coil, and stock ECU with NIStune. Really can't ask for more all things considered.
    Originally posted by Andrew84zx
    tell her your car is so fast it will make her panties fly off
    545 RWHP & 540 RWTQ

    Comment

    • mwolvinm
      #6.2
      mwolvinm commented
      04-04-2018, 12:08 PM
      I thought the factory MAF pegged out much sooner than that. Is it in a bigger housing?

      Those are impressive HP/Torque numbers… how do you keep your axles intact?
    • Coffeygr
      #6.3
      Coffeygr commented
      04-04-2018, 01:30 PM
      ^ ive been wondering about that myself the most i think about it, hard to think you could make 500whp on stock drawthru maf, maf tune really good ? Ik the 6262 can put down the power though
    • RedBeauty84ZX
      #6.4
      RedBeauty84ZX commented
      07-02-2018, 08:44 AM
      He's essentially maxed out the factory MAF at this point, but the factory MAF will read a bit over 500WHP.
  • #7
    I'm running a Precision Billet 6262. I use the E cover which is a 3" I let. The 4" inlet is useless on a drawthru. Having said that, your only looking for 300-350 I don't think you'll have any issue running that turbo.
    Originally posted by Andrew84zx
    tell her your car is so fast it will make her panties fly off
    545 RWHP & 540 RWTQ

    Comment

    • Coffeygr
      #7.1
      Coffeygr commented
      04-03-2018, 12:19 PM
      Sorry but what’s an e cover, I’m trying to visualize your set up
  • #8
    It's just a 3" compressor Inlet like this

    https://goo.gl/images/kAEG9N
    Originally posted by Andrew84zx
    tell her your car is so fast it will make her panties fly off
    545 RWHP & 540 RWTQ