JoeDirtPharmD

iTrader: (9)

After resolving my EBC issue and a few vacuum/boost leaks in the system, I was advised to have the UTEC retuned.

Orig thread: https://my350z.com/forum/forced-indu...ebc-issue.html

Took vehicle to UMS tuning (Tony) here in Phoenix; acclaimed to be a superior UTEC tuner in the State. Unfortunately, a new crop of issues arose while on the dyno (Dynapack).

• Issue 1: Car holds boost on the road (i.e. 14psi peak, tapers to 13.6 - 13.8 at redline), but tapered down to <10psi on the dyno. Each and every time. Turning up duty cycle to max while on the dyno, car will not boost beyond 13psi, let alone hold boost. Car was almost 100rwhp under target from GTM's reading. After the dyno, I was able to demonstrate that the car will hold boost on the road. *sigh*
  
• Issue 2: The rubber accordion intake (OEM APS item) is, in-fact, sucking in on itself while on the Dyno. I'll definitely need to address this as a repair.
  
• Issue 3: Oil is dripping from the turbo, and large amounts of smoke discharge after letting off the throttle. After looking under the car, it seems this has been an ongoing issue, though I check oil levels a couple times per week per Sam's suggestion

In light of boost not holding, no tuning or UTEC adjustments were done on the car. I was advised to do a leakdown/compression test, and it was suggested that cam timing might (also) be off because the car is losing power (and boost) above 5500rpms. The hp/tq curve mimics that of another local car with a TN setup built by Forged that ended up having less-than-favorbale leakdown results, so of course I'm less than excited about the possibility of having a similar outcome, though I presume the motor is just fine and this is a mechanical/electrical issues somewhere. Per Tony, however, despite turning up the boost, it has a negligible effect on timing or power increase.

EDIT:I failed to get a copy of the dyno sheet from UMS, and they're on vaca until next week. The only other dyno graph I have is from GTM at 12psi showing 471hp, but unfortunately, the tq/hp curves from UMS look totally different (12psi showing 393rwhp). So while I thought it drove great at 10psi, apparently increasing the boost doesn't do anything to enhance the car's performance. If someone rather I produce UTEC logs in lieu of Cipher logs, then allow me a day or so to figure that out...

Also, was told to look at incorporating an oil restrictor (0.035") for the oil issue?

As to why the car would hold boost on the road but not on the dyno, noone seems to have a suggestion for that, and makes tuning on the dyno a bit difficult at best...

So, I took a peek with Cipher, and something immediately stands out. Bank 2 CPS appears noisy, with abrupt changes of +/- 3* in a matter of millisec as opposed to the other bank (B2 is spiky vs. a smooth B1 when you look at the graph). The comparison base VQ has much less variance between the two banks (see attached pictures 3 and 4 below). My AFR corrections for each bank are odd looking compared to a base VQ also, both under load and at idle. Timing in 5th gear looks fawked... and driveability is greatly diminished in 5th/6th. Something looks amiss when you look at the .xls/.csv files.

Also, did a quick run to 120mph today (gears 2 thru 5), AFRs steadily in the low 11's, boost at 14.1psi and holding up to 6000rpms, but you can just feel that the power isn't there after 5k rpms. Picture 1 shows speed, RPMs, timing, and cam advancements, while picture 2 shows greater detail of timing and cam advances (B1 v. B2 cam sensors, and how noisy B2 is under load).

I realize that reviewing the data may be a bit time consuming, so if anyone that wants to take a stab as to how I should begin tracing my issue(s), I'd sincerely appreciate it. I've also included the .xls (Excel) and .csv (Cipher) files for your detailed veiwing pleasure Actually, there's a lot of data there such as throttle position, air metering, etc., that's not shown in the pictures above.

Files:
EXCEL: Comparison of APS ST vs. base VQ
EXCEL: APS ST run to 120mph
Cipher Data for APS ST under load

Pictures (greater detail):
APS ST under load (RPMs/Speed data)
APS ST under load (timing data)
APS ST at idle
Base VQ35DE at idle

JoeDirtPharmD

iTrader: (9)

Added new overlay showing intake cam solenoid activity. Is it normal that they disengage at 6k rpms? Also, someone pointed out that the base VQ35DE is pulling 160+ gm/sec of air on the MAF, whereas mine caps out at 134 gm/sec. Issue?

IIQuickSilverII

iTrader: (13)

wow dood... hope you get your issues sorted out!

terps

iTrader: (2)

im gonna second the leakdown/compression test given recent builds

KPierson

iTrader: (1)

What kind of flywheel do you have?

The UTEC has no filtering on the crank angle sensor. This caused my UTEC to not read my RPMs correctly on my JWT flywheel. I uninstalled the JWT flywheel and measured the distance between ticks on the reluctor wheel to find that their tolerances were all over the place. I reinstalled my OEM flywheel and fixed my jagged RPM issues.

I mention this because your RPM signal looks like it is a bit noisey as well. I'm not sure if this could be causing your issue, but it will really mess up timing if the crank angle sensor isn't reading right. The higher the RPM the small the window to get the timing right. If you look at your logs as you accelerate the RPMs should be constantly climbing - I noticed that that isn't the case in your car - it bounces around and stutters a bit. I would be very interested in seeing the actual UTEC data instead of the Cipher data as it will tell you more accurately what the UTEC is seeing.

However, with my issue, I never saw any problems in Cipher - it was always showing a smooth RPM curve. I figured this was because the OEM ECU averages the pulses, or perhaps reads the pulses differently then the UTEC.

It may not be the issue, but it is something to think about!

IIQuickSilverII

iTrader: (13)

i ran the utec with jwt flywheel for 1 year with no issues , worth checking out though

JoeDirtPharmD

iTrader: (9)

I, uh... have the JWT flywheel. I looked at the text data in the files and verified what you are saying. Small 30 rpm discrepancies from one data row to the other.

I have Thursday off, so I'll try to connect with the UTEC and log the data.

In comparing my data to others that have posted their Cipher data, my intake cam timing advancement isn't as high as other vehicles, whether that has anything to do with... well... anything.

KPierson

iTrader: (1)

Not knowing much background on your car makes it hard to offer ideas.

Do you have aftermarket cams?

The way the cam timing works is the ECU montiors the cam angle sensor on each cam. It can calculate cam timing (and engine position) based on the relationship between the cam angle and crank angle signals. I've never seen the cam angle reluctor wheel but I'm guessing that if it isn't timed correctly (say a tooth off) it can give false readings. The false input readings will CAUSE the output (control solenoid) to react in a manner that will lead to more jagedness because it is making adjustments to the position based on incorrect timing information.

I would also say the lack of air could be causing issues - however the UTEC is MAP based not MAF based. I would think the key would be that you are maxing out your MAF and your MAP continues to rise.

KPierson

iTrader: (1)

That being said, if the entire cam is timed a tooth off it could cause issues above 5500 rpm. I would verify mechanical cam timing.

Cass007

iTrader: (34)

If your guides are worn its possible that you could have jumped a tooth inside the cover. Not like you want that project though.

Lawy'dU

iTrader: (1)

this is insane bro! I hope you get everything sorted out. I doubt you are having issues with your flywheel. I hate to say it but when you said your car was built by GTM, and you are now having timing issues, I got suspicious....:

I'm not meaning to bash, and I just wanted to point this out since KPierson has asked.

UMS is a great shop. I'm sure they will sort everything out for you.

KPierson

iTrader: (1)

I made this graph for reference.

The top graph is NOT my car - it is Merlin3's Greddy TT 350Z with UTEC and OEM flywheel. Notice how smooth his RPM logs are (taken from his UTEC).

The middle graph is my car 1 year ago (APS TT G35 coupe with UTEC and JWT flywheel). The RPM issue is obvious and it made it near impossible to tune the car as the UTEC was constantly jumping cells while WOT.

The final graph was made this summer after Merlin3 and myself dropped my tranny and replaced the JWT flywheel with my OEM flywheel.

Remember though my Cipher logs always showed a smooth RPM, that is what has me concerned about your logs. Post up a UTEC log and we'll see what the UTEC is seeing. I didn't have any real issues with the way the car ran, but if your crank angle signal is that noisey it would effect timing much worse then mine did which could explain some of your problems.

I would still think you need to have your cam timing inspected as well.

leeboyNY

iTrader: (21)

I remember when I had my stock APS ST setup, I wasn't able to boost higher than 7.5psi on a dynojet dyno, but I saw 10psi on the road. Were you on a load based dyno? Perhaps, APS ST needs to be dynoed and mapped on a load based dyno or street tuned to see proper boost.

Did you check your scavenge pump? It could be failing. Thus not sucking out oil from the turbo fast enough..

I know you are quite the mechanic and you like to diagnose things on your own, but in my opinion, there are too many variables and unknowns in the play this time.. So, I know it's a long trip, but I say take it back to GTM... Stick with one shop through thick and thin. Now, let's not make this a witch hunt thread people... cough law'dU

IIQuickSilverII

iTrader: (13)

i dont think i has to do with the type of dyno, in either case you mised this

JoeDirtPharmD

iTrader: (9)

Alrighty - well, found my serial/USB adapter, so on Thursday AM I'll pull a couple logged runs with the UTEC and post the results. Thanks for all the possibly suggestions thus far... (tho, I guess I need a reference on how to check the mechanical timing without having to pull the front cover off...)

Sam@GTM

iTrader: (7)

Hello Don I looked at this briefly hopefully I didnt miss anything. let me bring up a couple of points. as I told you before we had a hell of a time on the dyno with intake on the turbo collapsing. once it does collapse you will obviously not be able to make boost not only that it will cause the turbo to suck a bunc of oil and the car will begin to smoke.

I am assuming you checked the pump and operation of the scavenging system. as far as timing concerns I am not worried about it because the engine does have all brand new chains, guides, and tensioners. If timing had jumped the car would set a code immediately, so the chances of haveing a misaligned timing chain and no codes are slim to none.

I also took a glance at the logs and what I have seen before there is always a variance of couple degrees between both banks. If there was anything that is abnormal again the factory ecu will set a code.

As far as noise and vibrations of the cam sensors that is were things get sticky. you have a utec which is inbetween the factory ecu and cams sensor, because that is how it controls timing.

Your maf voltage will be clamped at certain boost levels and that is also a utec feature so you will not see a progressive voltage increase once you reach that point it will stay the same, again this is one of the disadvantages of having a utec.

your injectors were pretty much maxed out at 500whp so I would really becareful pushing the car any more with out upgrade the injectors and or fuel system.

Below are the dyno graphs for the car when it left out shop, hope this will help I will give you a call tomorrow hopefully we can sort this out.





Sam

GT MOTORSPORTS

tig488

iTrader: (18)

good point about the intake collapsing. i did notice that the piece going from the compressor housing to the intake pipe was flimsy and would collapse. try with the air filter off. dave(cant remember his SN here) had a built motor with the APS ST and told me his pipe would totally collapse on itself under high boost.

JoeDirtPharmD

iTrader: (9)

Thanks, Sam, for the reply. I am presuming benevolence with regards to timing, I'd have to instill faith that it was timed correctly and that this is either an electrical (ECU/UTEC) or mechanical (collapsing intake) matter.

The intake is indeed collapsing under high boost, you can see that when on the dyno. Even with the air filter off, the intake will still collapse. At some point in mid-Jan I plan on addressing the matter by having a hard pipe fab'd, with hopefully better results. I didn't even consider that this may be contributing to oil intake, also I also appreciate you looking at the logs to see whether anything looked out of range/abnormal. As far as noisy sensor, I just wanted to rule out a bum sensor/ECU vs. mis-timed cam.

I'll try to have more info by Thursday afternoon, then after the intake piece is fab'd, have a compario available.

I don't plan on pushing it beyond it's current capabilities, mainly because I'm tired of putting money into the car (i.e. return fuel, larger injectors, upgraded ems, etc.) so I'll be happy if I can get it dialed in at/around 14psi DD.

More info to come - thanks again!

JoeDirtPharmD

iTrader: (9)

OK..... co-logged data on a 25 - 135mph run today with UTEC and CIPHER. Log files for each are available below the picture.

On the attached picture, a couple things:

• On the red line (UTEC timing), where it zeros out, the logs indicated that timing was controlled via ECU and did not record a value. I guess I don't understand why the timing logs between the software are not similar in values?
  
• Boost holds up to, then tapers off remarkably at 6000rpms, which is what UMS was observing as well. Interestingly, this drop is not observed on either of my two boost gauges (Autometer and Blitz), and everything (UTEC, Autometer and Blitz) is tee'd off the same vac line...? WG spring pressure is 10psi... so why the discrepancy with UTEC? What's happening at 6000rpms (other than the cam solenoids not engaging)? Additonally, both boost gauges record a 9% variance in boost (13psi Blitz vs. 11.9 UTEC)
  
• Per log data, RPM increase is not consistent.

So, as before, any suggestions or opinions are appreciated!



Log files:

CIPHER data
UTEC data

KPierson

iTrader: (1)

I don't think your RPM data looks that bad - not as smooth as it should be but not near as bad as mine was (see my graphs above for reference). It is interesting to see how much smoother the OEM ECU reads RPM then the UTEC.

The reason the timing is different is because the Cipher is reading OEM ECU timing. The UTEC is NOT passing the OEM timing values through to the coil packs, instead it is using it's own timing values. Timing is not a value that can measured by the ECU, so it goes by tables - it has no way to know when the spark plug actually fires. The UTEC timing value, when the UTEC is controlling timing, is the correct value.

I would try replumbing the UTEC MAP sensor - I know Merlin3 had some issues with his UTEC and boost guage not reading the same value until he changed some lines around and it got better. The UTEC MAP sensors don't seem to be that accurate but accuracy really don't matter as long as the values given are consistent. When tuning of course you always want to go off the UTEC MAP sensor because that is what the UTEC is using. There are calibration values for the UTEC that you can play with and may be able to get the MAP sensor to read closer to your other gauges.

I would be EXTREMELY concerned if your UTEC MAP gauge is dropping pressure off after 6,000 RPM but your other gauges arn't. I would trust the others for accuracy, but remember your UTEC won't be supplying the extra fuel needed for the extra pressure - that is a great way to run the motor very lean up top.