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Secondary Butterflies always open
Hey I was just wondering if anyone else has heard anything about this.
Today I was in class and I had my car in on the hoist. My engine's teacher came by and asked me if I wanted to shave 1 second off my times. I laughed and him and ask him how. He put my car down and told me that he could shorten my intake runners for a little more power. He said that our intake runners are originally short, but by keeping the secondary butterfly open all the time, we could get more kick our of our motors. He basically showed me how the secondary butterfly opens and how it's vacuum related. So he told me to take the hose that goes from the vacuum diagphragm to the solenoid, and take the other vacuum hose that goes into the lower part of the solenoid, and link them together, bypassing the solenoid for constand vacuum going into the intake manifold. So when we started my car, we instantly saw the little spring on the vacuum diagphragm flip up (open). He told me to go take it for a rip and come back and tell him how it feels. I don't know if it's just me, but it definately pulled harder, and definately changed the sound of my exhaust before/after v-tec. Anyone heard about this? I'm still skeptical about it shaving 1 second off my times :wtf: He claims he knows engine's so well that I just have to trust him Anyone want to shed some light? |
*waiting for the Tman to comment*, sounds kewl though
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Yea it's pretty cool. I'm still running my car like until someone gives me reason not to. I understand the part about having constant vacuum in the intake manifold by bypassing the solenoid. And I understand about having the secondary butterflies always open because it's vacuum actuated, I just dont understand the 1 second thing haha
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dunno if this helps, but i don't have secondaries and my car runs fine. if i had them in the first place, i wouldn't have removed them, my intake manifold came that way.
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i think that type R's and B16's and even LS's intake manifold's have a one stage butterfly, and the GSR's have a two stage. when you remove or keep open the second butterfly i think you loose low end but it helps on the high end around the time where vtec kicks in. don't quote me, but i remember reading something about this.
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^ the LS intake manifold doesn't have the two-stage for sure. I was reading that shorter runners give you more high-end, but my teacher said something about better at low end when I launch, and he also said something about it being better when I'm trying to pass someone on the highway and I gear down.
My car is still running like this and so far no problems. |
that's why it's popular to switch to the ITR intake manifold or the skunk2 intake manifold. both of which have only one butterfly.
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