R34 GTT load scale not tracing

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Chris250
 

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Joined: Thu Jul 03, 2014 1:16 am

R34 GTT load scale not tracing

Post by Chris250 »

I'm having great fun with this GTT!!!

Changed the AFM for a Z33 so I could get a good resolution through out the rev range, trouble is since changing I've not had the load scale on the fuel mixture map trace across the X-axis of the map.

I've attached the log and bin file.
Attachments
NIStune_2015-01-27_1009_18.csv
(48.5 KiB) Downloaded 143 times
R34GTT-Z33-DW700cc.bin
(64 KiB) Downloaded 166 times
Matt
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Re: R34 GTT load scale not tracing

Post by Matt »

Its been a common issue which is seeming to come up today (with all models!) where the TP tickbox is becoming unticked in the latest versions

Display > Select Consult Registers

Tick the 'TP (load)' or the 'BFuel Schedule (TP)' tickbox to enable load tracing again!

I'll make a fix this week to force it back on!
Chris250
 

Posts: 16
Joined: Thu Jul 03, 2014 1:16 am

Re: R34 GTT load scale not tracing

Post by Chris250 »

That's great, thanks Matt. I'll give that a shot in the morning
Chris250
 

Posts: 16
Joined: Thu Jul 03, 2014 1:16 am

Re: R34 GTT load scale not tracing

Post by Chris250 »

Gave that a shot and it was already selected. When I unplugged the MAP sensor and switched off the faults it started tracing across the map as it should.

I'm getting another problem that I thought was the standard maf going hugely rich once it starts to boost, or when I'm full throttle. What's the usual suspects for this? To scaling?

R34 GTT
bigger turbo
cat-back exhaust
FMIC
Blitz SUS cone filter
DW 700cc injectors (hate these things)
Z33 AFM
Matt
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Re: R34 GTT load scale not tracing

Post by Matt »

Try pulling back your injection multiplier a bit so its not running so rich. Once you have that right, adjust your TP scales on your fuel and timing map

The log you posted showed no 'TP' register selected initially
Chris250
 

Posts: 16
Joined: Thu Jul 03, 2014 1:16 am

Re: R34 GTT load scale not tracing

Post by Chris250 »

Back on this GTT again, Matt could you look at these logs and confirm there's nothing the ECU is doing that could cause the misfire, it's load dependant from the looks of things so I'm guessing that the ebay coils just aren't up to the task
Attachments
NIStune_2015-02-27_1642_39.csv
Full throttle boost set higher than achieved
(135.87 KiB) Downloaded 133 times
Chris250
 

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Re: R34 GTT load scale not tracing

Post by Chris250 »

data log from dyno run
Attachments
r34misfire.jpg
(412.54 KiB) Downloaded 3715 times
Chris250
 

Posts: 16
Joined: Thu Jul 03, 2014 1:16 am

Re: R34 GTT load scale not tracing

Post by Chris250 »

bin file and short data log with low boost
Attachments
NIStune_2015-02-27_1651_50.csv
(19.04 KiB) Downloaded 120 times
r34gttZ33afm700ccmisfire.bin
(64 KiB) Downloaded 171 times
Matt
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Re: R34 GTT load scale not tracing

Post by Matt »

fuel maps need a bit of cleaning up. You have it going too rich and then lean. Normally with an R34 it goes up smoothly and then flattens out, not a valley at the top end

You can see this in your dyno graph also, it goes richer at 3000rpm and then goes leaner. You want a nice smooth curve once you've reached your target boost AFRs

Regardless of this, the logs arent showing me anything showing problems with timing. I'm seeing about 21 degrees timing at the top end and 10ms injection time until you get the ignition cut around 4500rpm.

The cut appears unrelated to the tune itself, so would be looking at the plug gap and coil setup
Attachments
r34_trace.png
(152.11 KiB) Downloaded 3698 times
Chris250
 

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Re: R34 GTT load scale not tracing

Post by Chris250 »

Thanks Matt, just needed that confirming. I know the tunes a mess, I've started with a blank standard tune and just addressed the areas this misfire to try ruling out the tune
Chris250
 

Posts: 16
Joined: Thu Jul 03, 2014 1:16 am

Re: R34 GTT load scale not tracing

Post by Chris250 »

double post
Last edited by Chris250 on Tue Mar 17, 2015 9:18 am, edited 1 time in total.
Chris250
 

Posts: 16
Joined: Thu Jul 03, 2014 1:16 am

Re: R34 GTT load scale not tracing

Post by Chris250 »

Eventually!!! a set of genuine Nissan coils off of a low mileage engine and we have a finished map, one little miss half way through the run but apart from that all good. I really should have just stuck to my guns at the start and got a set of decent coils in

https://www.youtube.com/watch?v=_q2VIcw36Oc
Attachments
R34 GTT.jpg
Final figures
(77.63 KiB) Downloaded 3655 times
Matt
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Re: R34 GTT load scale not tracing

Post by Matt »

Yeah the coils in these are old... mine are giving up on me also. Looking for replacements soon
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