Drift Tengoku — September 2004 · Page 83
Page 83 — English translation
ECU tuning reflects each tuner's personality and experience. The same car can end up with different characteristics. We invited 3UP's Mikami to compare approaches, but matching cars were not available, so we'll study his data.
It looks good, and my figures would probably be similar. The car is an S13 with an S15 turbo, standard intercooler and restrictive exhaust, a common beginner drift car specification. Broadly, the tune emphasizes low and middle rpm response, which is felt strongly in street driving...
...of advance, based on experience, to help it pull at higher rpm. Second is the region between vacuum and positive pressure. The map suggests very sharp response and careful optimization.
I taught Mikami this area: it does not change peak output, but transforms initial response when you press the throttle. Ignoring it wastes the value of individual tuning. However, this degree of optimization may be aggressive with the stock intercooler, since high intake temperatures can cause knock.
Without driving it I cannot judge, but might retard it one or two degrees for margin. Maps reveal these things. This is not a criticism: Mikami spoke with the customer and drove the car...
Captions and page details
Instructor: Kazuyoshi Okamura, Yashio Factory representative
With ten years of ECU tuning and over 2,000 Silvias, the self proclaimed Silvia god can infer specification, faults and calibration from maps, logs or simply driving. Although he now does less hardware fitting, he insists on performing road testing and tuning himself.
Special guest: Masami Mikami
...since street drivers are not always at full throttle. Two aspects matter. First is high rpm, high load calibration, which governs full throttle feel and response when reapplying the throttle. Mikami leaves a fairly generous margin here, perhaps to cover street and circuit use or a first time tuning customer...
3UP representative
Around two years of ECU tuning, but exceptionally diligent research has earned his mentor Okamura's approval. He refuses to compromise, reportedly traveling as far as Niigata to tune a car. He also competes in D1 Grand Prix.
A different tuner...
...means a different tune.
...or concerns about the engine lead to extra margin...
...which is a valid approach. Even so, it is more carefully optimized, with more advance, than many generic ECUs and should be quicker. Above 6,000 rpm the S15 turbo runs out of capacity and boost falls. I would consider another one or two degrees...
...for reassurance. But...
These road test logs are clean. At the arrow, boost begins falling; adjusting that map region could extend useful high rpm power. On the rpm and ignition graphs, timing jumps as rpm falls during an upshift. That is when the reading point moves from the map's right edge toward the middle.
A healthy car is essential before tuning. Many PS13s arrive with faults, and Mikami invested considerable work making this example ready. It uses an S15 turbo, Tomei Type R cams, GT-R fuel pump, S15 injectors and an RB20 airflow meter, with the factory intercooler.
...so he will have reasons for his settings. My point is that even the same car can receive many different tunes. Find a good, experienced tuner and discuss your requirements carefully.
Tuning knowledge is a tuner's asset, but I willingly teach people who ask. Mikami first approached me at Tsukuba two years ago and has contacted me repeatedly since, especially when stuck. His enthusiasm for research is good...
Equipment used: Neko Corporation DL700 data logger and AF640 air fuel ratio meter. Both tuners use them. Nissan factory ECU maps share orientation, making comparison easy; V Pro, Techtom and Toyota maps have a different orientation.
...I think.
Can you see the difference here?
Now I understand!
81
About this issue
ドリフト天国 (Drift Tengoku), September 2004, is a Japanese drifting magazine. This archive preserves 316 scanned pages in their original right-to-left reading order, including the covers.
English translations are available through the outlined text areas. Hover over a box on desktop, or tap it on mobile. The original photographs and Japanese lettering remain visible on the scan.
Reading the magazine
Use the page buttons or page number to navigate. On mobile, drag with one finger to move the page and pinch with two fingers to zoom. On desktop, drag a corner to turn a page. The zoom controls allow a closer look at the scans.