Vararam vs. flip tie mod
Race Director
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St. Jude Donor '03
And with all due respect, who really cares what static pressure is upstream of the TB, or especially upstream of the filter? 
MAP is what matters. It's the best indicator we have as to how well the cylinders are being filled. A pretty simple parameter to scan/log too. If an intake design is more efficient, there should be a noticeable increase in MAP at WOT. It's that simple.
And if air truly was "rammed" in (a debate for another time), one should expect to see MAP values exceed that of atmospheric pressure (commonly known as boost).
MAP is what matters. It's the best indicator we have as to how well the cylinders are being filled. A pretty simple parameter to scan/log too. If an intake design is more efficient, there should be a noticeable increase in MAP at WOT. It's that simple.
And if air truly was "rammed" in (a debate for another time), one should expect to see MAP values exceed that of atmospheric pressure (commonly known as boost).
Drifting
Joined: Jan 2008
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From: Florida
St. Jude Donor '09
And with all due respect, who really cares what static pressure is upstream of the TB, or especially upstream of the filter?
MAP is what matters. It's the best indicator we have as to how well the cylinders are being filled. A pretty simple parameter to scan/log too. If an intake design is more efficient, there should be a noticeable increase in MAP at WOT. It's that simple.
And if air truly was "rammed" in (a debate for another time), one should expect to see MAP values exceed that of atmospheric pressure (commonly known as boost).
MAP is what matters. It's the best indicator we have as to how well the cylinders are being filled. A pretty simple parameter to scan/log too. If an intake design is more efficient, there should be a noticeable increase in MAP at WOT. It's that simple.
And if air truly was "rammed" in (a debate for another time), one should expect to see MAP values exceed that of atmospheric pressure (commonly known as boost).
Race Director
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St. Jude Donor '03
Melting Slicks
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Drifting
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From: Florida
St. Jude Donor '09
The increased pressure measured at the air bridge was 11" of water @ 70 MPH in 6th gear. The pressure down stream of the butterfly valve will also increase but only by a fraction of what is observed on the inlet side of the valve. At those low levels I don't believe the MAP is accurate enough to sense the minor increase.
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St. Jude Donor '03
The increased pressure measured at the air bridge was 11" of water @ 70 MPH in 6th gear. The pressure down stream of the butterfly valve will also increase but only by a fraction of what is observed on the inlet side of the valve. At those low levels I don't believe the MAP is accurate enough to sense the minor increase.
At WOT, a n/a engine ideally should have MAP equaling atmospheric pressure. You'll find this never quite happens, but the closer you can get to it, the better performing your intake tract is.
Drifting
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From: Florida
St. Jude Donor '09
70mph in 6th gear = what, 1500RPM. Yes, I imagine you could find some pressure upstream of the TB in such a condition. And as I asked, who cares? I thought we were talking about which intake would make more power?
At WOT, a n/a engine ideally should have MAP equaling atmospheric pressure. You'll find this never quite happens, but the closer you can get to it, the better performing your intake tract is.
At WOT, a n/a engine ideally should have MAP equaling atmospheric pressure. You'll find this never quite happens, but the closer you can get to it, the better performing your intake tract is.
Race Director
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From: Gone
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St. Jude Donor '03
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Drifting
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St. Jude Donor '09
Race Director
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St. Jude Donor '03
You claimed the atmospheric pressure of the Vararam housing, and under the shroud measured about the same. Does that automatically mean MAP will be the same between the two? NO.
And that's all I'm sayin'.
You seem to be more concerned about what goes into the intake, where I'm more concerned as to what comes out of it.
Drifting
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From: Florida
St. Jude Donor '09
I can see that this is pointless conversation with you. You can't even bring yourself to admit that atmospheric pressure variations will have an effect on engine performance by increasing or decreasing it's pumping losses. Happy new year.
Race Director
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St. Jude Donor '03
I'm sorry if you cannot understand that. You claim pressures of both systems (at inlet) are equal. What you have not claimed is if pressures at outlet of both systems are equal.
Quite frankly that nasty-sharp 90° bend of the flip-tie setup could very well be a contributing factor, doesn't your fluid dynamics expertise tell you that?
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St. Jude Donor '06-'10, '13
Lots of test and research went in to it. There is a reason why it is so popluar, and has so many proven results here on the forum. If the "flip tie" mod worked so well, many others would have used that and figured it out, rather than spend $$$ on v-ram. I've been around this forum since 01, and a few others. V-ram again and again comes up as the best choice.
