| response through the midrange which resulted in slightly higher boost in that range. This contributed to an increase in torque through that range, however, given the small increase of torque relative to the small increase in boost, I feel that there is a zero-sum difference if all things were equal. The new design has vastly better flow properties than the OEM plenum. From my professional opinion the improvements in flow characteristics of this new design vs. OEM is capable to the effect of offsetting the trend we would expect of trading off low end for high end power. The plenum chambers are also significantly larger which provide a larger "well" for the runners to draw from through the peak torque RPM range... to the effect of improving flow characteristics in the RPM band where one would expect there to be losses in favor of top-end power. I modeled the OEM manifold as well to get a baseline from which to compare my design to. I used transient flow modeling over 500-RPM intervals for both the OEM and the new design which also corroborates these findings. Additionally, if you look closely at the graph below, you can see that even though there is a boost bias between 4300RPM and 5000RPM, from 5000RPM to 5500RPM the boost is the same in both tests. And you can also see that there is ~20RWTQ and ~20RWHP gained in the new design.. And the A/F is nearly identical as well. And the most impressive of it all is the gains in the top end. Both the boost and A/F are spon-on with each other through the upper end and these gains are exactly where these calculated-length runners were designed to optimize. 
Enthusiasts soon understand each other. --W. Irving.
Are you an enthusiast? If you are out to describe the truth, leave elegance to the
tailor.
Albert Einstein
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