R34 GTT RB25DET Weird Dyno Results

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soltek2002
 

Posts: 13
Joined: Fri Jul 04, 2014 11:00 pm

R34 GTT RB25DET Weird Dyno Results

Post by soltek2002 »

Hey

Just recently had a Nistune computer installed in my car and tuned
Mods Completed
Stock Bottom End 150,000km (Good compression)
Automatic Box with Shift Kit
Stock Manifold
Turbo - Turbonteics Series 60-1 billet 61/82mm comp wheel, F1-62mm ex wheel. 0.65 ex housing
540cc Injectors
Z32 AFM
Tial MV-R 44mm Wastegate directly welded onto exhaust housing
Tomei Poncams - 260 degree
Tomei FPR
GFB Electronic Boost Controller
Tial BOV
Blitz FMIC

There aren't any tuners really familar with the Nistune software in Auckland so I struggled to get it tuned.
Ended up taking it to ST Hitec (Highly respected Auckland based tuner) who said he would give it a go.

The graphs just seem a little weird to me but keen to hear your feedback
Attachments
Photo 2 Boost Levels.jpg
Boost Levels
(361.82 KiB) Downloaded 5792 times
Photo 1 Dyno results.jpg
Dyno results at different Boost Levels
(433.69 KiB) Downloaded 5792 times
284 kw dyno run.jpg
Top Dyno Run with strange dip
(428.29 KiB) Downloaded 5792 times
Last edited by soltek2002 on Mon Jul 14, 2014 6:53 pm, edited 2 times in total.
soltek2002
 

Posts: 13
Joined: Fri Jul 04, 2014 11:00 pm

Re: R34 GTT RB25DET Weird Dyno Results

Post by soltek2002 »

Also attached is the Bin file for those who like to play and investigate
Attachments
Dion R34 Z32AFM 540cc 1.2bar 264kw tune.bin
(64 KiB) Downloaded 185 times
s200rat
 

Posts: 36
Joined: Sat Sep 13, 2008 10:19 pm
Location: Scotland

Re: R34 GTT RB25DET Weird Dyno Results

Post by s200rat »

what ecu are you using?

im reading the bin using the AA5xx ecu tables.

Using that then it looks like the use of nistune hasn't been understood. The primary fuel map is ~14.7AFR throughout. Also it doesn't appear Kconstant value is in the right place for your mods.

I personally wouldn't drive it till you sort out the primary fuel table, you must be running off the knock maps all the time
soltek2002
 

Posts: 13
Joined: Fri Jul 04, 2014 11:00 pm

Re: R34 GTT RB25DET Weird Dyno Results

Post by soltek2002 »

Attached is the latest ECU tune I pulled fem the car. If anyone wants to have a look please let me know what you think
Attachments
ecu map r34.bin
Latest tune
(64 KiB) Downloaded 156 times
Matt
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Re: R34 GTT RB25DET Weird Dyno Results

Post by Matt »

Oh crap. Problems...

1. K constant is quite low (lean) 421 compared to my calculated 628 (540CC/Z32 AFM)
2. Is your Z32 AFM confirmed genuine?
3. If you hold at 2000rpm does your STFT and LTFT sit around 0% trim?
4. Most of the fuel map is in closed loop (128 = closed loop value) and basically flat. There is no extra fuel added except for a small patch
5. Scaling is completely off. I very much doubt TP should be going upto 240 on the fuel and timing scales

My auto calculated values sit between TP = 28 .. 179. I doubt half of the fuel/timing map is being read with the current scaling

They need to do some reading on tuning Nissan ECUs. We have workshop documentation there on our website or they can call me. I think it seems like were trying to flatten maps to achieve AFRs. Not sure...
soltek2002
 

Posts: 13
Joined: Fri Jul 04, 2014 11:00 pm

Re: R34 GTT RB25DET Weird Dyno Results

Post by soltek2002 »

So from what your telling me the tune is dangerous to drive the car on and is probably leaning out on high RPMs?

Z32 is genuine can confirm that.
Will plug my laptop into it this weekend hopefully and test it at 2000rpm
Also I gave them the 80 page doc from your website. Printed and in colour
Matt
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Re: R34 GTT RB25DET Weird Dyno Results

Post by Matt »

The training notes are probably the most helpful ones. Software users guide is good for how all the software works but the training covers tuning specifically and how the ECU functions
soltek2002
 

Posts: 13
Joined: Fri Jul 04, 2014 11:00 pm

Re: R34 GTT RB25DET Weird Dyno Results

Post by soltek2002 »

Matt wrote:The training notes are probably the most helpful ones. Software users guide is good for how all the software works but the training covers tuning specifically and how the ECU functions
I think I printed the whole set of docs. (Just checked what i had downloaded)

Should I get a second tuner to take a look?
Matt
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Re: R34 GTT RB25DET Weird Dyno Results

Post by Matt »

Yeah I wouldnt leave it like that...
soltek2002
 

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Joined: Fri Jul 04, 2014 11:00 pm

Re: R34 GTT RB25DET Weird Dyno Results

Post by soltek2002 »

Could a tune like that possibly lower its it power figure?
s200rat
 

Posts: 36
Joined: Sat Sep 13, 2008 10:19 pm
Location: Scotland

Re: R34 GTT RB25DET Weird Dyno Results

Post by s200rat »

100% yes, that tune will not be making anywhere near the power the car should deliver.
nanook
 

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Location: Auckland, New Zealand

Re: R34 GTT RB25DET Weird Dyno Results

Post by nanook »

Either take it back to Sochi and get him to read up and view the comments here or see if Torque Performance will do it.
Address:37 Patiki Road, Avondale
09 828 7054
soltek2002
 

Posts: 13
Joined: Fri Jul 04, 2014 11:00 pm

Re: R34 GTT RB25DET Weird Dyno Results

Post by soltek2002 »

Yeah taking it back to him hopefully in the next week or so. Just hard finding the time. He only did the original tune as a favour through a friend. Last thing I want to do is bag his work when I've seen the amazing work he's done with F-Cons, Links and PFCs on RBs. Was originally going to go to Torque but there Nistune tuner left.
nanook
 

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Location: Auckland, New Zealand

Re: R34 GTT RB25DET Weird Dyno Results

Post by nanook »

Yea he has a good rep for sure, I think he just hasn't had much experience with factory ECU, he did my Nistuned R32 years ago which went very well afterwards.
soltek2002
 

Posts: 13
Joined: Fri Jul 04, 2014 11:00 pm

Re: R34 GTT RB25DET Weird Dyno Results

Post by soltek2002 »

So just took the car for a spin and noticed it had a fuel cut keep coming in at high RPMs, decided to take the laptop out with me for a test drive and check what was causing it. Turned out it was the factory boost fuel cut in the ecu coming on at 0.6bar

Thanks Matt for the latest Rom packs. Quick change in there and I was away laughing no more boost cut :D
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