air flow meter question

[TopStreet240]

hi im looking today at my air flow meter and thinking gosh thats small, what are you guys running, and where did you get it. also what size injectors does the 240 have stock. these things i must know before i order the turboThanksjake

[king_johnthegreat]

Size of the MAF sensor has nothing to do with its actual value to the system, its weight is measured in voltage. Hacked MAF's and upgraded units from other platforms add the ability to see greater hp figures because they do not max out their voltage capabilities at a point below the turbo systems ability to supply air at increased volume and pressure. There is some insight into this printed by Dave Coleman (I hope I spelled his name right) in SCC, in a series addressing their Project Silvia. There, he outlined some of the options offered by JWT to use a Cobra MAFS for up to 350 hp and/or a 300ZX TT MAFS for up 500+ hp. "Size" doesn't matter, it is the voltage that counts.John

[revlis240]

The stock KA maf is good till about 260hp before it maxes out, what kit did you order? the stock KA injectors are 270cc's good will about 4 psi, and then you blow up. the stock maf and 370cc injectors are the most commonly used setup, both good till about 260rwhp.

-Abe

[WDRacing]

Well a larger MAF will flow more volume...but your not gonna need that till you have a larger TB as well as piping.

WD

[TopStreet240]

thanks much guys, i will look over all of this. Im going to be running on 440cc injectors, and im not sure what kind of MAF i will be using.

[WDRacing]

I'll be selling MAFS recalled for 370, 440, and 550 as soon as I get back. Should work out well from what I've learned from the guys here and reading. Plus I have free access to a dyno for all my test and tune sessions. Makes things real nice.

WD

[TopStreet240]

well when you get back, please contact me email is [email protected] thanks

[TopStreet240]

Size of the MAF sensor has nothing to do with its actual value to the system, its weight is measured in voltage. Hacked MAF's and upgraded units from other platforms add the ability to see greater hp figures because they do not max out their voltage capabilities at a point below the turbo systems ability to supply air at increased volume and pressure. There is some insight into this printed by Dave Coleman (I hope I spelled his name right) in SCC, in a series addressing their Project Silvia. There, he outlined some of the options offered by JWT to use a Cobra MAFS for up to 350 hp and/or a 300ZX TT MAFS for up 500+ hp. "Size" doesn't matter, it is the voltage that counts.John

how do you know that it can support 500+ hp, do you have one on your car or are you just guessing

[zachosz]

It's all about airflow man!!!

[Turbo 510]

The 370 cc TT injectors along with a stock MAF and JWT computer are a sweet set up for a "plug and play" system. This set up is good to about 260-275HP until the MAF voltage is maxed out. To go futher, you need a Cobra MAF and some 60lb/hr./550cc injectors as well as an upgraded ECU. This will get you to some serious HP figures (I have seen claims of 400+ HP but who knows). I have done the 370 cc/stock MAF/JWT computer route and it screams pretty good. Of course this assumes you have done all of the required internal upgrades to ensure your motor stays together.

[matt147]

Is there a JWT KA program for bored out stock mafs? Thats a popular setup for fwd SR20 turbo kits paired up with 370cc injectors and 4bar fuel setup. It has been taken to 300whp (about the max for the setup).

[Turbo 510]

Again, as mentioned somewhere above, the name of the game is voltage not flow. Boring out a stock MAF might yeild some benefits but why go to the expense when you can own a cobra MAF for about $100? There is a JWT program for this set up the only other requirement is the addition of 550cc injectors. You can either use the Nismo ones which drop into the stock fuel rail or get some MSD 50 lb/hr ones and fab your own fuel rail. I have all of the stuff for the Cobra upgrade but have not installed it yet due to the fact that I an still getting used to the 370cc set up in a very light car.

[matt147]

Its about airflow as much as voltage when it comes to the stock SR20 maf. The reason we go with that setup is the the 370s flow about 430cc at 4bar and boring a maf out is cheap. That way you don't have to buy a Cobra maf and larger injectors but you can max out a GTiR T28 setup with S3 or S4 cams and make about 300whp. If you are running a t3 or up then by all means get a Cobra or Z32 maf and MSD 50 or 72 # injectors but why bother spending all that extra $ for more capacity then you need?

[MarkEmark]

The stock KA maf is good till about 260hp before it maxes out, what kit did you order? the stock KA injectors are 270cc's good will about 4 psi, and then you blow up. the stock maf and 370cc injectors are the most commonly used setup, both good till about 260rwhp.

-Abe

4 psi and then they blow up, huh? Seems to me XS, FMAX, and NSPORT all run reliably at 7 psi on stock injectors...Where you sourcing this info from?

[C-Kwik]

4 psi and then they blow up, huh? Seems to me XS, FMAX, and NSPORT all run reliably at 7 psi on stock injectors...Where you sourcing this info from?

XS and NSport use a rising rate boost dependent fuel pressure regulator. Abe was referring to a completely stock fuel system. fuel injectors are rated at a certain fuel pressure. If you increase the pressure it increases the actual flow. The FMU that XS and NSport use raise pressure as you boost. So the injectors actually flow more than the rating of the injector. I'm not exactly sure what FMax uses to increase fuel now.