I built up the NA motor before switching to turbo. Toda 264 cams, Greddy sub-computer, header, DIY intake and ran 4.3 & 4.6 gear. I only ran at Ebisu and Fuji so I needed a variety. The factory 4.1 otherwise had no grunt out of the corners.
The 4 throttle was next on my list but then I started to work out the pricing and I gave up. Just not cheap for a full kit.
This fella in Japan did it right with a custom kit from Ikeya Formula, again though he probably has 2500-3000$ in the throttle set up alone. Original Ikeya 4 throttle set up was meant for turbo car.
http://minkara.carview.co.jp/userid/...9/profile.aspx
Youll have to translate that page to understand his full spec.
Link to Ikeya kit -
http://www.ikeya-f.co.jp/category/1968248.html
If you can get the flange your better off making full custom kit to save on money.
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