JWT can program your ECU based on Z-32 injectors and mafs. Has anyone gone this route? Specifically, will the Z-32 mafs bolt right up to the SC charge pipe?

 

Ummmmmmmmmmmmmmm... It's alot to type.

Let me see if I can scrounge up some time.

 

Thanks, Delio.

 

p.s. I take it this means it's not a simple bolt-on? (Other than the electrical connection, that is, I know that needs some modifying.)

 

The Z32 MAF is the same size (physically) as the Maxima MAF, but it can meter a greater amount of air flow whereas the Maxima MAF maxes out. I don't know exactly how the Maxima MAF attaches to the SC piping, but I don't see any reason it wouldn't work.

The Z32 MAF has 4 wires: signal, 2 grounds, and power,and is really easy to hook up.

Stephen if you need more technical information I can pass you on to someone who knows considerably more than I.
-hype
-hype

 

Thanks, Matthew, this is exactly what I needed to know. I'm having my ecu sent to jwt soon, and I thought I'd have them program it for the z-32 mafs as well as the 370's.

 

Cool 2 new additions I really want to see how your car turns out once you're done with everything. I've only ridden in a SC car once, but I'm trying to learn as much about boosting as I can.

I'll get the wiring colors for you so you don't have to dig it up. FYI JWT is pretty much right on when they tune the ECU/injectors, but when you first start up the car it will run a little lean until it gets used to things.
-hype

 

as delio will elaborate on, the z32 maf NEEDs to be on the non charged side.. forget what you know about the max maf... we have been spoiled by the amount of boost it can handle.

and yes, you will need to locate a harness for the z maf.. its a 6pin that utilizes four of them.

 

Well, that complicates things. I saw somebody's homepage where they cut the flange off of a maf and attached it directly to the blower inlet, with the other end attached to cai pipe going down into the wheel well. Does anyone remember who's homepage that was?

 

Brett is right, JWT will tell you that you need to put it on the non-pressurized side. I took a gamble and put it on the pressurized side and the car would buck heavily and 0 vacuum and not go into boost well. As soon as I moved it over to the non-pressurized side that problem went away.

The issue that crops up when you put the Z32 maf on the non-pressurized side is that now it is BEFORE the BOV, meaning that you are blowing off metered air, not like the "stock" setup where the BOV is before the MAF so it has not been measured yet. This causes some driveability problems. Namely backfiring coming down to idle, because you blow off, but as far as the MAF knows you are ingesting that air into the motor, so the car runs really rich because it dumps fuel for now non-existent air, and a hunting for idle issue which JWT also warned me about. In order to correct this you need to use a re-circ valve. I have not finished my re-circ setup yet, I am working on it, but Stephen, if I remember correctly you are a machinist, or have enough connections to them. What I am doing is having a MAF tube made for the Stillen Setup. Basically replicating the Stock MAF out of Aluminum, with the flange and all in order to avoid cutting up the stillen piping, and to avoid having to use my stock maf in there which is a restriction, and an expensive part to replace. I am having a new flange made for my Blitz BOV with a 1" nipple on it, and having a 1" nipple welded onto the piping for my CAI after the MAF so that I can run a tube from the BOV to the CAI piping. This should fix my backfiring issue at the least, and hopefully help with the hunting for idle issue. I got a MAF adapter for the MAF and finished up the intake with a cone filter, and some silicone couplers. My Z32 MAF sits in the fender well... I had to run some longer wires obviously, but it works. I can honestly say that with the ECU and the MAF and Z injectors, my car pulls much harder now than it ever did with the FMU, it seems to just run dead on, the backfiring and idle issues are a small price to pay, but I hope to have them at least partially resolved by the end of the weekend. All in all, I would say that the setup is definitely worth it. I was not sure at first, but after moving the MAF to the non pressurized side, I definitely became a believer, and I will swear by this setup. I will swear by it even more if I can get the backfiring to stop.

I was told that the AFC has a decel function which may eliminate the need for the re-circ, but my theory is that JWT has been on point so far, why not take them at their word? I can always go back to my vent to atmosphere setup in a matter of minutes if I need to, or if I want to test the AFC functionality, but for now, re-circ it is.

Another bonus to the JWT setup, and I cannot really attest to it too much since I really just got her running right this week, but Brett (confused) can, is that Gas Mileage is significantly improved, so in theory, the upgrade will pay for itself over enough time.

 

Thanks Delio!!! I really appreciate you taking the time to get this all down in writing.

So a Z32 mafs before the blower with a recirculating bypass circuit is the ticket.

By the way, I'm only a mechanical engineer, but I work at a research lab that has a machine shop, so I can occasionally get a machinist to do some personal work for me.

One last question - the recirc circuit should go from the bov to someplace before the blower but after the mafs, correct?

 

I know mechanical engineers well, I work at a site with 2 power plants... hahahahaha

In regards to how you would setup the re-circ, you got it right, from the BOV back to the non-pressurized side of the setup, but before the MAF or the air will just get metered again, and the air you were trying to put back into the system will register as new air if you get my drift.

Anyways, I can't swear that that will fix the backfiring issue, but in theory it should, and I am betting it will.

 

FWIW; 370cc injectors w/z32maf are only good to 420 crank HP, 555's are good till ~600 crank HP.

IMHO SC~12psi @7000rpm w/MEVI and good exhaust is very close to the limit, if not over.

Del & Brett, please take some duty cycle readings for me!

My ecu is in the mail, 7-10 week wait now.

 

Hi Matt,
420 hp sounds awesome enough for me. What boost pressure do you think I'll get with a 3" pulley, MEVI, 7200 rpm?

 

V2 12
v1 11

Monitor MAF voltage or Injector duty cycle to be sure.

 

Won't 370cc injectors @ 4 bar fuel psi max out closer to 440-450hp? Also I read that the Z32 maf is good for 500hp too, but then again I could be wrong. I know that generally 370cc injectors in a I4 engine (SR20DE) at stock fuel psi would max out around 230-240hp (crank). However at 4 bar (58psi) + a bored MAF that setup would max out around 260-280hp @ crank. If someone was to get the JWT program I'm sure they can specify it for a 4 bar base fuel pressure vs stock 3 bar. Hell the se-r guys do it all the time and its proven to up the limits of our stock MAF/370cc injectors.

 

if we release to atomosphere and run rich and backfire, then would this be true for the 300zx guys as well with a bov. just wondering, how or why did is different. thanks in advance delio and matt. later.

Ferhan

 

Interesting idea, I supose if you needed a little more head room thats a good idea for NA. On paper (Excel)using 95% duty cycle 0.55bsfc on a boosted V6 car with 1:1 fpr at 12psi you only pick up ~53bhp (415bhp/468bhp) going from .3bar to .4bar. On a boosted car it's part of the equation 1:1 fpr. I suposed if you were close to the edge of the 370's you could do this as long as you didnt think you were going to ever add any more mods. But if your gonna buy injectors and an ECU just get the 555cc's and call it a day, your good till 622bhp (close to the limit of the Walbro GSS342HP) with the same specs as above at 3bar. CRANK IT UP!!!

 

Now that is true also. General turbo setups for the SR20DE are 370cc injectors/stock maf/3bar, 370cc/bored maf/4bar, 50lb/hr MSDs/cobra maf/3bar or 4bar, or 70lb/hr MSDs/Z32 maf/3bar. However for people that like to push the limit nothing wrong with 550cc injectors @ 3bar fuel.

 

Thanks to all who participated in this thread - I learned a lot!

Based on information given here I bought a Z32 mafs this weekend and just got through talking with Ben at JWT about the ECU upgrade. I already had the 370 cc/min injectors, otherwise I might have gone with the 550's, but I can't take advantage of all that extra hp right now anyway. Gotta do a few intermediate steps like exhaust upgrade to 3" and LSD first.

Plus, to really take advantage of the 550's is going to require some form of charge air cooling, right? At that point it's better just to switch from SC to turbo, I have the feeling.

 

Thanks Delio for the info. I have my ECU rolling around on 240 floor board waiting to ship. Also going with ZMaf and Inj. I think I understand about the recyle. If it works could you post pix for us slower folks

Damn 7-10 weeks?!!! Anyone wanna sell they're JWT 97 Zmaf/Inj for a little more to an impatient Max dude?

 

How?

 

How much are Blitz 550s?

 

Blitz and Greddy 550s are big money, heres a nice alternative->

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2429064294

 

Those 550's on e-bay will fot our fuel rail but require a harness plug from a Subaru. The harness plugs from a 2k2 VQ35 work if you shave the alignment pins off the side of the plug on the side of the injector.

 

hell that beats paying over $900 for Greddys and the Blitzs run about $700-800 for a set of 6, not sure if the $150 "install kit" is necessary though as well

 

$100 per injector is GREAT!

What's the difference physically between those and the 00-01 injectors?

Any way to mod them to work?

Also, it says HIGH IMPEDANCE, so are you sure they'll work? I know if you get to much difference from stock impedance injectors, you'll *** the ECU up.

 

Impediance is the same, high. I dont know about VQ30DE-K injectors, sorry. Where theirs a wallet, theirs a way.

 

BUMP!

For updates / pics / instructions of the recommended z32 maf non charged side install!