So here is my dyno:



Mods -
V2 Blower - 2.87" Pulley
300zx injectors
MEVI
JWT ECU w/370cc/A32 MAF program and raised limiter
Stillen Exhaust
WSP Y-Pipe & B-pipe "Fix"
Straight Pipe (No Cat)

If you look at the Dyno, pay attention to the blue run. in the red, the MEVI wasn't open (we ended up zip-tieing it open because my check valve broke and it wouldn't work under boost).

Above 6500RPM or so, I start to lose power fairly rapidly. Someone suggested this is because the A32 MAF is getting a bigger airflow than it can detect.

Do people here concur with that? Does anyone have any Dynos of a similar configuration with the Z32 MAF so I may compare Dynos?

Basically I want to make sure I'm doing the right thing before moving on to having the JWT ECU Reprogrammed and putting the Z32 in....Basically, will it help?

Anyone know what the Max voltage on the A32 MAF is so I can measure what I'm getting vs what the Max is?

Thanks!
IanS

 

Well I cant answer your Z32 maf questions since Im 5thgen, but I wanted to chime in to let you know that you should take it easy on anything past 6300rpm cause if you look at your charts, your A/F is in dangerous territory. Especially your blue run. Went above 13AF and almost close to 14:1 A/F ratio. Definetely dont want that pushing at 7000rpm. Im suprised the dyno guy didnt cut the run short, most do once they see 13-13.5 flash on the screen.

Dixit

 

Thanks. I was aware of that an never take it past 6500 until I get this issue resolved.

Interestingly, the one or two times on the Dyno I did take it to full RPM, the EGT's were at 1350.

 

bump.

Anyone have any comparative setups or have experience with this phenomenon?

IanS

 

10987654321

 

My bet is you are at 100% duty cycle on the injectors. You should do the Z32 MAF and have JWT do a program for the 370's at 3.5bar of fuel pressure. The extra fuel pressure will take car of the lean condition w/ 370's.

 

Interesting. It seems many people out there run up to 350whp with these injectors and no problems.

I hit 65PSI under full boost at high RPM (a little over 4bar)

I idle at about 40PSI.

Hmmmm. Any way to verify that is the problem besides just trying another ECU?? (Basically, is there a way to calculate real-time injector cycle?)

Should I just put my Cartech back on and have that raise the FP at high boost?

Thanks Mardi - you're always a big help.

 

I want to chime in and give you props for your progress so far. I saw a vid the other day of a 3.8 turbo grand prix that put down just slightly more than you currently put down. Your working with .8 litres less! that's great Ian, keep up the progress.

 

Thanks tampamax!

Unfortunately, looking at Dynos like JAY25 and Confused, I feel I should be getting somewhat more power. I'm thinking I should be in the 335-345 range at this point.....Strangely, the 3" exhaust doesn't seem to help much. At least my "Butt Dyno 2000" tells me so. Could be I just got quickly acclimated to the addition of power. .

I need to get to a Dyno soon it looks like anyway - maybe measure the MAF voltage peak and see what I get while I'm there.

Anyway - just trying to get the bugs worked out as always. And I know some people on this board have experienced similar hurdles on their road to "perfection".

I certainly am happy to drive her however.

 

OK Mardi - I think I misread your post.

I get what you're saying now. I'll give JWT a call this week and talk to them about raising the Fuel Pressure and the Z32 upgrade.

 

I bet you are maxing out the MAF. The samething happens to se-r's when out stock maf maxes out (hits 5.1v around 250whp). Its too bad you don't have an OBD-II logger, it would be nice to see how many lb/min the car is flowing at redline.

 

Ian, there is no garauntee that your will put down the most given the same set up cause there are too many variables to consider(different dyno's, elevations, humidity, etc, etc). More often than not its the driver that win a race and not the machine. That's half the fun/stress competeing with the others. But always keep in mind that you are putting down very respectable numbers from less displacement than most. Remember to enjoy her now as i'm sure there is much more left to be dicovered. Good luck

 

There is no garauntee of perfection, only the struggle for it.

 

Preach on brother tampamax.

But tinkering and learning is also what it's about - which is what this is.

I am in no way saddened by my numbers. I just am sure I can improve a little more.

Speaking of the Dyno I use, a couple of the locals have also complained that it put down lower numbers than they expected.

So that is likely a variable that is there.
But it's $40 an hour - can't complain too much about that!

 

Can't beat 40 bucks an hour even if i was standing in the middle of a room full of 2 cent hookers with a 100 dollar bill in my pocket.
The good thing is once you got your baseline you will still be able to accurately see the progress made or not made regardless of how low the dyno reads. As long as its consitant. Wish we could get that kind of deal on dyno time. Around here dyno's get $75 for 3 pulls or $125 for an hour.

 

Z32 MAF is a great idea. I am going to a Z32 MAF and stock ECU for now. What PSI did you see when you did these dynos runs?

 

About 11.5-12PSI.

 

I just spoke with Ben to check on my ECU status, it is still not done.

Your situation does worry me as we will be using similar setups.

He feels that our setup is good for 420 at the wheels and we should not need to increase the stock fuel pressure.

He would like to discuss this issue further, maybe do some consult testing?
Please call JWT 619-442-0680 to discuss it.

BTW, you are using a Walbro gs342 right? stock fpr?

Please keep me informed. This is when I would need to request 3.5 bar FP for my ECU. :>

Ben did not seem to like the idea of me going to 3.5 bar stock fuel pressure.
What are the calculations you did to come up with 3.5bar?

You really think we are near 100% DC on the 370s?!?!

 

I called JWT twice, and each time they said in a very rushed tone "Go on a Dyno and measure your max votlageo n the MAF". Seemed like they were trying to get me off the phone quickly and when i tried to go into detail, they cut me off.

I also have sent them 3 E-Mails with the Dyno and with all the information, and haven't received one answer.

Getting a little sick of dealing with them.

I have a Walbro GSS342 installed, A32 MAF, 300zx Injectors, 2.87" Pulley. The JWT is programmed currently for this setup.

IanS

 

Well I Just talked to Ben and said the person having the lean condtion is Ian in Seattle. I say you call right now. I had to wait about 6 minutes to get Ben.
You can also reference your emails or heck have them check this thread?

 

Ok - I just talked to Ben.

He thought you said that I have the Z32 MAF right now - THAT is good to 420hp. I don't have a Z32 MAF yet. That's what I'm trying to figure out if I need.

He said the A32 Maf (Maxima MAF) is good for 350hp at the crank, or about 290hp at the wheel.

i am hitting 320hp.....370 at the crank.

So this all makes more sense now. It does look to be the MAF. This is all stuff everyone's been telling me all along, i know - I'm just a stickler for not spending my money until I'm completely 100% convinced of something. Sorry if that annoys anyone.

He said the injectors themselves with the Z32MAF go to about 420hp also before hitting 100% duty cycle.

IanS

 

Werd. So you've have indeed been maxing out the MAF everytime when your uptop. It's nice to know you will have some headroom now with the injectors.

S

 

Sometimes you learn more by working through this kind of thing yourself, but you do risk blowing an engine by not learning from others. Glad you got it sorted out before anything bad happened.

 

Next question:

I will have no reprogrammed ECU for a few weeks while this gets done. I apparently can buy an FPR, bump the FP down to 26, and run around with the stock MAF and ECU until then without boosting and just driving mildly - correct?

IanS

 

I am still waiting on my ECU, and I am not boosted yet.

I am running a32 ecu and MAF with 370 injectors and a SARD FPR.

I had to lower my FP to 26. My car runs nicely at WOT even.
It stalled and bogged down at stock FP.

EDIT: sorry I cannot read ehe

 

I was thinking just to be safe I'd put the stock belt on and disengage the SC while I'm waiting.

I need a FPR anyway so I can go and pass emmissions later this year with these injectors.

Because I have a 97, I get a CEL from the JWT ECU that is not clearable (1005) - In Seattle, if you have any codes whatsoever, no matter if their related to emmissions or not - they fail you. So I'm just going to reset the stock 5spd ECU (it throws a P/N switch code usually) and drive over there without the SC attached and with the FPR and A32 MAF.

If they complain that my computer is in open-loop, I'll just stare at them blankly and give them a . "What's an ECU?"

So in conclusion, I need to buy a FPR to pass emmissions anyway - so I may as well buy now.

IanS

 

Just so its clear, 420 crank HP, not wheels.

Raising the fuel pressure is a viable option, easy to program too, just a basic variable, no MAP reworking, should be simple.

 

Yep - got that. 420 crank.

I don't expect to be reaching that any time soon. According to my math, I'm at 378hp at the crank now.

Looks like i simply need the Z32 MAF program.

the next question is - looking at my Dyno, will fixing this add power or simply richen it up and be safer?

 

It will add power because the Z32 MAF has a finer voltage scale than the A32. This allows JWT to tune much more precisley.

 

Well, can't beat more power at less than $200 (Z32 MAf and ECU)!!



Now i just need confused to get back to me on that Z32 MAF and Adapter to put it on the non-charged side....

 

Ask him about the ECU he has sitting at home too... it may cut your wait time down.

 

We need someone to do a group buy on a z32maf non-charged side intake piping. Remember that the z32 maf needs to be at least 18 inches from the blower inlet.

 

Whoa.

Never heard that before. Where the hell do you put it? My CAI isn't even 18" long!

 

It's a problem. I think the only way is to run a maf crossover pipe like the 5th gen Stillen kit has.

I started out with the maf in the wheel well, about 9-10" from the blower inlet and I had real problems with the maf detecting backflow from the blower whenever the throttle closed, such as when shifting or just backing off the throttle. I knew I was getting backflow because my injector duty cycle meter would light up to 10% whenever I shifted. This resulted in frequent momentary richness that eventually fouled my plugs in less than a thousand miles.

I solved the problem by putting the maf back on the charged side, against JWT's recommendations. I've been running it there since about the beginning of November. No problems with the maf so far, and I boost up to 10-11 psi pretty regularly, and I've gone as high as 12 psi. I datalog my maf voltage, and I haven't seen any signs of sensor degradation. Yet.

 

Ben at JWT. *This is mostly from 300zx experience I imagine.*

He said you would have problems since the MAF can read in and out.

He said it can make your car do weird things getting "negative" air from the blower inlet. He stressed AT LEAST 18 inches.

How far away is a 5thgen maf on their kit?

EDIT: sorry I was working on this post in between calls at work so it took me awhile and I did not see stephens post.

 

the 5th gen piping is beyone 18 inches, Id have to say at least 36 inches

 

Ok - so it looks to me like I have 2 options:

1) Put the MAF on the charged side against JWT's reccomendations and just wait for it to blow.

2) Build an 18" long CAI, remove my washer resivour and make it work somehow.

Confused just sent me a PM - he has some things I might be interested in purchasing for this - here is his PM:

Alright - I know what a k&N Filter is obviously, but I'm wondering what a "z tube like stephan had posted on a while ago" is....is that for making it 18" away from the blower? Is it a recirculaiton tube? Is this setup on the non-charged side at all?

I sent him a PM with these quesitons - but maybe one of you can help.

Also, he's going to see if Ben at JWT can just transfer his EEPROM he already has with them over to me so I don't have all the downtime. But I was going to send them my Dyno and have them tune according to that.

But I don't even know if that's worth doing.

Thanks
IanS

 

and there is no way this 5th gen intake pipe will work in my 4th gen without damaging it?

So we need a good source for a custom at least 18 inch intake pipe for a 4th gen. :>

 

I have an ebay link of the tube, I will see if I can find it.

 

That is what I used to connect the Z32 maf to the blower inlet. It is an oem tube that is part of the Z32 intake:



The recirc hose attached to the little vent tube. The left end of the tube is about the same OD as the blower inlet, I used some boost hose to connect the two. The right end was a snug fit over the maf outlet.

Like I said, this did not provide enough distance away from the blower.