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Old 09-04-2014, 07:47 PM   #136 (permalink)
phunk
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The evidence that the stock manifold does really well shows in the dyno graphs this car is able to produce. Guys are making over 350rwhp all motor. That is well over 100hp per liter, and that is with only a 7600 rpm redline.

Intake manifolds are a lot like camshafts, there is no perfect geometry. You can shift the power around with different manifold specs... but unless you started with a really poor design to begin with, you are not going to make power without losing it somewhere too. Manufacturers have overcome much of this effect in camshaft tuning by engineering variable valve timing, lift, and duration systems. Intake manifold geometry can also be variable, but it is not cost realistic for the basic aftermarket performance industry at this time. Most factory equipped variable manifold geometry is hokey at best. Space constraints is one of the largest factors to overcome in manifold design for factory production vehicles. Nissan did a pretty good job with the VHR intake manifold and its packaging. Ugly or not, it works well.

The GT-R manifold is different because its a different car. The GT-R manifold looks like it is built with more torque in mind. Probably because the car is heavier, has a lot more drivetrain drag, and uses a DCT transmission which has some characteristics similar to driving an auto trans. It is also a lower compression engine than the VHR. The GT-R needs more help in the torque department than the 370z does in order for it to feel motivated and exciting.

I suspect that putting the VR38DETT intake manifold on a VHR engine would result in a loss of power, but increase in throttle response and torque.

My manifold will do more than look pretty, but it is not being designed to compete with the stock manifold. Its being designed around a different set of priorities and it might come at a sacrifice of versatility. It is unlikely that I am going to beat Nissan at their own game on this one. I am building mine with different goals.
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Last edited by phunk; 09-04-2014 at 07:59 PM.
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