What is one of the biggest mistakes both professional and amateur tuners make when it comes to setting AFR targets?
This lightly modified RB26 powered Nissan R34 GTR Skyline made 485whp with light knock occurring at 22-23 psi, and with only minimal changes planned it was expected to make LESS power to ensure reliability. By taking the time to check what AFR targets suit this specific setup rather than assuming what has worked for one RB26 tune will work for all, the result was an increase of power to 528whp at the same boost level, with no knock.
In this [TECH TALK] Andre explains why this was possible, why some tuners wouldn't find this power out of not necessarily bad habits but rather clock focused, along with some of the causes of knock and where they sat in regards to this specific project.
Also discussed are the Z32 airflow meters that were fitted in Japan, along with their removal, and the upgrading of the trigger system without breaking the bank (as if you own a recently purchased R34 GTR these days, no doubt your account is already pretty empty!).
0:00 - Nissan R34 GTR
0:45 - Existing Mods (From Japan)
1:31 - Z32 Airflow Meter Upgrade
2:07 - Owners Goals
2:40 - 485 WHP at 22 Psi Base
2:57 - Problem Found, Causes Explained
4:42 - 360 Degree Trigger System Out
3:37 - 24 -1 Trigger System In
8:00 - Lambda Sensor Upgrade
8:40 - Emtron KV8 PnP
8:58 - 4 Bar Map Sensor
9:19 - Turbocharged ITB Tuning - 4D Mapping
10:18 - Expectation - Less Power
11:04 - Reality - More Power
13:15 - Why? Not Using Fixed AFR Ratio
13:55 - Dyno Run
14:23 - Learn More Here Cuz
Nissan RB26 Modifications:
Apexi Power FC replaced with an Emtron KV8 PnP Unit
Apexi low mount turbos
Aftermarket exhaust and intercooler
Larger fuel pump
Sard fuel rail, 800cc injectors and adjustable fuel pressure regulator
Z32 airflow meter x2 - Removed
Tomei cams and cam gears
GReddy intake kit
NZ Wiring 24-1 reluctor trigger system
4 Bar MAP sensor - Display function only
485whp base, 528whp finish
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