How aggressive is the GTiR timing table?

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fwlrmusic
 

Posts: 11
Joined: Wed May 19, 2021 12:15 pm

How aggressive is the GTiR timing table?

Post by fwlrmusic »

Hey! I'm new here but have been tuning my DSM for the past decade.

I recently just built a GTiR for autox. I built the motor with 10:1 JE pistons which makes it pretty snappy but with the 92 octane fuel I'm concerned that the timing table is pretty aggressive.

With the GTiR I have a second knock sensor bolted to the block and I monitor the signal with headphones as well as record it to my tuning laptop. I am fairly new to listening to knock (my DSM has a pretty good knock detection system) so I am not 100% confident in my ear.

This past weekend my girlfriend and I raced it in an autocross. When she was doing her runs I recorded the log and the knock sensor and synced them up which you can watch below.

https://youtu.be/7DaN2yuR2nE

I pulled a ton of timing out of the map and added a lot of fuel to be safe (its hitting between 10-11 AFR) but I still think I'm hearing knock in the midrange. listen to 0:25 and 0:47 for examples. I forgot to turn on the wideband in the log unfortunately.

Basically just wondering if anyone has experience with the stock RNN14 timing tables when using shite gas and high comp pistons.

Here's a breakdown of the build in terms of the engine:
10:1 JE pistons
Stock valvetrain
Water - Air intercooler (works amazing)
53mm CX turbo with a 0.63 AR hotside
Custom tubular manifold
Precision 29mm wastegate (15psi)
stock fueling / maf (i've got ID 1050 and an AEM meth kit in the mail)
no bov
insufficient half-rad from previous owner (hence the high coolant temps)

Any advice would be really appreciated!
-Nick
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GTiR Autox Tune.bin
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unex
 

Posts: 86
Joined: Sat Aug 06, 2011 6:59 am

Re: How aggressive is the GTiR timing table?

Post by unex »

my advice is not related with your question, but still:

1. Fix load resolution. You dont need half table with same ignition timing. Better use more resolution on high load.
2. Nissan ecu is not good at fast throttle transition (in terms of ignition timing), so I recommend lowering low load timing, because on fast throttle movements it picks high values and knocks in areas where you usually would not knock on steady throttle. I mean situations where in high rpm you hit throttle very fast and hit high load areas instantly.
fwlrmusic
 

Posts: 11
Joined: Wed May 19, 2021 12:15 pm

Re: How aggressive is the GTiR timing table?

Post by fwlrmusic »

Awesome thank you! that makes a lot of sense. I'm used to the tables having fixed axis's's's in my DSM. I'll scale down the low load areas and lower the timing a bit in those cells.
fwlrmusic
 

Posts: 11
Joined: Wed May 19, 2021 12:15 pm

Re: How aggressive is the GTiR timing table?

Post by fwlrmusic »

Hows this look?
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unex
 

Posts: 86
Joined: Sat Aug 06, 2011 6:59 am

Re: How aggressive is the GTiR timing table?

Post by unex »

need some work with timing, but I would say its much better now
fwlrmusic
 

Posts: 11
Joined: Wed May 19, 2021 12:15 pm

Re: How aggressive is the GTiR timing table?

Post by fwlrmusic »

Just an fyi for anyone who may find this in the future - the discussion continues here: https://www.hpacademy.com/forum/general ... any-timing
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