JUN GT Surge Tank was developed using all the experience and know-how that have accumulated from our entry in GT Racing in Japan. We designed it to improve the power endurance during the high rotation (that usually does not last long). We also researches thoroughly about the shape of collector tanks or curl funnel shape on the top of intake manifold and it includes all outcomes of the researches. The Surge Tank for RB26DETT was developed for the Vennevile Speed Trial 1997. This left a very good result.
CAPACITY of SURGE TANK
Since a stock surge tank is not taking into consideration the increasing in an output by tuning, it may become the shortage of capacity. If the capacity of a tank runs short, good air distribution in each cylinder will become difficult. However, if capacity is too large, it will hard coming to obtain the inertia boost effect that sends air into each cylinder using pressure change. That is, if the capacity of collector tank is too large, pressure change of each part will become mild. The capacity of highly efficient surge tank is made in consideration of the above-mentioned point. The difference of inhalation efficiency could take in the difference in the high rotation region that appears greatly.
FORM of FUNNEL
It is important to pass the flow of the air in a serge tank, in the optimal condition of the funnel of each cylinder. As for the inside of the stock surge tank, the branch to each cylinder has not projected. This type with which the hole is opened on the side of a tank is almost the case of a stock. The efficiency of the funnel does not improve, even if the upper air is made easy to inhale. Because in practice, since air is near the entrance is inhaled according to a pressure difference, the air not upper part of the funnel but near the entrance is inhaled. Downward air (nearby air) can be efficiently taken in form a funnel entrance by making the inside of a tank into curl funnel form. High inhaling air efficiency is realized.
FORM of SURGE TANK
It is important for the form of the surge tank to design so that it may lead to the funnel of each cylinder, without decreasing the movement energy of the air near an entrance. Many of stock surge tanks have a thick form. Although it is considered that it is likely to be easy to pass along air since appearance is thick, movement energy changes to disorder of a whirlpool etc. on the way, and as for it cannot keep a proper flow to a back end. By making it taper form towards a back end from the entrance of a tank, air can be passed smoothly, without reducing the vigor of a flow. Furthermore, removing useless capacity can heighten the inertia boost effect.
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