Interesting dyno results..., doesn't look good.

[zxtman]

I have a problem, and I'm not sure what else to do.

On my 280ZXT, I am running a Jim Wolf Technology setup (reprogrammed Z31 ECU, 420cc injectors, and Ford MAF sensor). The engine would develop an intermittent lean condition while in closed loop (even while idling) and was undriveable, especially under full load. When this would occur, the green light on the ECU would blink. I spoke to Jim wolf and he said that this was impossible. But asked me to send him the ECU so that they can "bench test" it. I did, and they could find nothing wrong with it. Jim asked me to perform a few tests, which I did.

... check all sensors providing information to the ECU (MAF sensor, cyl head temp sensor, Oxygen sensor, throttle position switch) to make sure they are working properly and to make sure that all signals are within range. All sensors cheched out OK. Under full load, the MAF sensor was sending a signal of 4.9+ volts to the ECU. Jim said this was OK.

 

When I ran the car without the oxygen senson connected, the intermittent leaning condition was gone, so the condition only occured in closed loop.

 

I put the car on the dyno expecting somewhere in the 420 HP range, but that didn't happen. The outcome was 350 HP and 380 torque. The curves were steep from 3000-4000 and the steadily dropped off after 4100 rpm.

The interesting thing is that both of these HP and torque numbers occured at right around 4100 rpm which happens to be when maximim boost is reached (the turbo is a 60-1, TO4 w/ P-trim wheel and .70 A/R). Both HP and torque dropped after 4100 rpm and the the air/fuel ratio went completely rich, off the chart.

I would expect max horsepower to occur in the 6000-6500 rpm range and max torque to occur in the 5000-5500 range.

 

I gave this information to Jim Wolf and he said that he could perform a "shotgun" procedure to the ECU. This meant obtaining another ECU, and transplanting the reprogrammed circuit boards from the original to the new. He said this would not necessarily solve the problem.

 

Has anyone had an experience like this?

Does anyone have any ideas for a solution?

 

This has been an ongoing and frustrating experience. I'm considering going with a stand alone, fully programmable system.

 

I'd appreciate any help.

 

Spiro

[Lockjaw]

First of all, screw dealing with Jim, talk to Clark, he knows what is going on. Jim is a pompous ass. Call Clark BEFORE lunch, he programs after lunch and they won't let you talk to him, and he is also usually really busy right around the end of the month.

 

JeffP and I are both running the same set-up, and I don't run the O2 sensor, mainly since I always have some 110 leaded in the tank.

 

Have you had the fuel pressure map converted to 4 bar or had a step added to the ecuu? You should because you are close the the max voltage the ecu can put out. Your turbo is to large to be running a standard map.

 

Is your maf at least 18 inches away from the turbo? You have to have it that far away from the turbo to keep turbulence down.

 

What is the O2 sensor voltage when it is idling? It should read about .47 volts, if it oscillates, you likely have your TPS maladjusted.

 

Your HP numbers are pretty strong, but you need to spend some phone time with Clark to get your set-up dialed in. Be patient it takes a little time, but it can be done. Mine works well, and I should be up again with a bigger turbo, larger intercooler, 4 bar map and step and will post an update.

 

Finally, I always encourage everyone to disconnect the harness at the ecu and clean the connections with brake clean and reconnect.

[240Z Turbo]

First of all, screw dealing with Jim, talk to Clark, he knows what is going on. Jim is a pompous ass.

How wonderful it must be to own a Jim Wolf setup!

What, you mean they were not able to tune your car without your car being there? COME ON PEOPLE......WAKE UP! You CANNOT expect someone to send you a map based on your particular combination. 9 times out of 10 it WILL NOT be right! You mean they just had the computer dump fuel under boost? WOW, great tuning!

 

Sell the JUNK and get yourself a programmable ECU.

[BLKMGK]

FWIW - max torque around max boost is what I believe the Supra usually see. That's how the Supra guys judge the spool of a Turbo based on a dyno graph. The earlier it spools the earlier the torque peak it seems.

 

Don't rely on the stock O2 for A/F readings, they're generally just good for stoich - period.

 

It IS darned hard to tune "long distance". It'll be an interative trial and error thing. They've probably got a pool of calibrations they've used in the past with various mods but EVERY car is different so don't expect perfection anytime soon. For that matter the end result will likely be a compromise anyway...

 

Personally - I prefer a programmable EMS too but that takes patience and time too <shrug>

[Z-Gad]

STAND ALONE!!!

 

pretty descent numbers though...

[Lockjaw]

What a bunch of nay sayers. Telling him to get a stand alone really helps when he has the JWT set-up.

 

dynoing it with a wideband and sending the info to Clark will get it in the ballpark, and I dare say, he will do a better job getting things right then some novice trying to tune his stand alone. (I am not implying you are a novice)

 

Tell the whole story about what you have to do to get the stand alone dialed in, its not plug and play.

 

I am not knocking the stand alone, it is the best way to go, but its not for everyone.

 

The simpliest solution is to call Clark and let him work with you to get the car dialed in. JeffP posted some big numbers with a smaller turbo then you have, there is no reason why you can't get similar numbers.

 

You have to work on it, just like with a STAND ALONE.

 

[Mudge]

Sometimes stock computers have thier limits, alot of the time they can be worked around though. One of the biggest limits in my experience so far though is only RPM related, and in a turbo car thats probably not going to matter a bit.

 

Going stand alone is usually so fargin costly though, tuning it yourself is the way to go. As for mail order stuff, with dyno data he should be able to do ok with it if hes worth his weight in beans, as for blind mail order tuning, that is a total crap shoot, some are happy with it some are not, potentially dangerous for a non-NA car though.

 

Good luck with the car.

[clint78z]

Well first you should record the blinking lights, then go to an ECCS manual and find the trouble code. Either your harness and senors are failing or JWT got his programming wrong and is giving an out of range error.

 

You won't get power up that high rpm unless you change the cam or do some head work.

 

As far as an opinion on JWT setup it's a mixed bag. It will get you a very well behaved 350hp out of the box. If you are happy with just that it's not a bad way to go. If you goals get big and package changes and you want to extract maximum out of your combination, be prepared for alot of time on the phone and a poking with a stick in the dark to get that extra power. This is when the programmable makes more sense. I live far from a dyno, so I need something I can tune myself.

[Lockjaw]

Look you can't expect to buy a box, throw it on your car and get 420 hp, you have to tune it, just like with a stand alone.

 

Fortunately for you, several people have gone beyond your power level so Clark will have the data needed to help. Your mistake is dealing with Jim.

 

Call Clark and he will take care of you, just realize he is the real brains behind the orgainization, not Jim.

 

Also if you got 350 hp and your engine is stock, you are doing really well. You can get more, but you need to look at a cam change and some head work.

 

The nicest thing about the JWT set-up besides stock like reliabilty is that once you are dialed in, making minor changes like swapping cams or turbo's don't monkey stuff up like they do when you have a speed density, which means you don't have to retune it.

 

I like mine, but when I reach the end of what it will do, then I will go to a stand alone, until then, I will deal with Clark.

[zxtman]

Thanks for all the replies and input guys.

 

To answer some of your questions:

 

1. Fuel pressure map is set at 3 bar

2. No "step" has been added to the ECU

3. MAF sensor is approx 16" away from compressor inlet with (2) very slight bends

4. A/F readings were from wide-band O2 during dyno session

5. I have the stock cam in the car (I have my new cam & adj. cam sprocket sitting in a box until I get the ECU problem sorted out. new cam will move the power band up to better match the power band of the turbo)

6. Head is race ported

7. SS valves & upgraded valve springs

8. Intake runners are fully ported incl. plenum area

9. Larger throttle body

10. HKS 4 Row I/C

11. Custom fuel rail, SI FPR, Aeromotive fuel pump

12. GReddy BOV

13. Custom 3" downpipe & exhaust

14. Turbonetics Racegate

15. EVC IV

16. Rods, pistons, rings

17. Crank, dampner, & tilton flywheel balanced

18. All internals stress relieved & balanced

19. Cast oil pan w/ trap doors & windage tray

20. Custom 3" Griffin radiator

21. Spal dual elec fans

22. MSD

23. Coil-overs w/ caster/camber adj

24. Custom roll cage

25. Race seats w/ 5 pt

26. Z32 brakes front, Z31 brakes rear

27. Nismo LSD

28. Z31 CV axles

29. 5 lug front & rear

30. 17x8's & 17x9.5's

the list goes on...

 

I am going to put the car on a different dyno to make sure the results are consistent. Then, I will call Clark, provide him with the dyno results, 4 bar fuel pressure map, "step" program added to the ECU, and go from there.

 

Regarding the blinking ECU light(s), the first thing I did was to check the manuals ECCS section to find what the trouble code was for. It was for an ignition problem. I offered this info to Jim Wolf and he replied that the codes are not valid since it is a Z31 ECU. And again, he stated that the blinking green light was impossible and offered no other help.

 

I know, I know, I'll speak to Clark.

 

thanks again for the input.

[clint78z]

That is pretty arrogant thing to say it is impossible to happen. I forgot that is a Z31 ecu non turbo he uses, mabey go to Z31.com and try and find the trouble codes for that ECU.

 

Not to take credit away from the time JWT has put into cracking the ECU, but it isn't rocket science. The stock ECU still works exactly like the stock ECU. He simply modifies the values in the registers on the chip which hold information for fuel and ignition settings. By adding on another board he is simply adding more space to store his values and gives better resolution.

 

If the crank angle sensor in you distributor starts to go south, it will still give you the same trouble codes as a stock Z31 non turbo. The only difference now is mabey his programming could be wrong in the ignition map and will give you a faulty ignition error.

[Lockjaw]

No it is modified more than you think it is. I personally wouldn't put much stock into anything Jim says, he is a pompous ass.

 

You need the 4 bar map you have to much turbo for a 3 bar map, and you most definitely need the step added. Whoever sold you the system did not question you properly, and I would make that point to Clark, he is a good customer service oriented guy,, and should take care of you.

 

If your head is ported, you could probably step up to a larger cam and pick up some performance. The stock cam for the Z's is small.

 

I would also tell Clart how far the MAF is from the turbo, it is supposed to be at least 18 inches away, but he may be able to make some mods to your map to compensate. May take a few try's for him, but it can be done.

 

Mine is out in front of the radiator.

 

Make sure you have a good pump, and JWT has a good FPR made by Bosch that they can sell you that will help you raise the pressure and keep the stock 1 psi increase in fuel pressure increase per pound of boost.

 

You are on the right track, it just takes a little work to get it dialed in. When it is there, you'll know it.