Tony had to drop some pistons off over with the fine gentlemen at Rebello Racing, and being as they have a flow bench... well, it just seemed like some testing was the right thing to do. We grabbed a stock outlet we had laying around, and one of the new outlets right out of the bin they get pulled from for shipping. We asked Dave if he would mind some back-to-back flow testing. The guys are Rebello Racing are awesome so they didn't hesitate to stop everything they were doing in order to indulge us.
We didn't do anything fancy, as this isn't a fancy test. We ran all tests at 28" of water, which is standard for most flow bench tests. The flow bench they use is an SF-600, which can flow up to 600 CFM. You can read specs about it to your heart's content at this site: http://www.assurich.com.my/engine-dynamometer-system-superflow-sf-600.htm
We began by installing the stock outlet on the bench using a 2.5" silicone adapter and turned the machine on. Dave does A LOT of flow testing, so his guess that "Range 4" was about right was dead on. Range 4 has a maximum flow of 295 CFM at 28" of water. Results showed it flowed right at 73% (of 295 CFM), so the stock outlet flowed 215.4 CFM.
With no setting changes, we pulled the stock outlet off and put on the VTT aluminum outlet. When turning the machine back on, it flowed 100% at 28" of water -out of range (high) on Range 4 and Range 5. Dave laughed and said "you maxed out my flow bench" as he rarely has to use "Range 6". Dave schooled Tony on the topic after testing and explained how if you have ranges left unused, once you hit above 75% you'll always want to go up to the next range and bring the flow percentage down into a more reasonable range for more accurate readings. Range 6 has a maximum flow of 597 CFM at 28" of water. When Dave turned the machine back on, we could see that the VTT outlet flowed 59% (of 597 CFM), so the VTT outlet flowed 352.2 CFM.
The VTT outlet flows 1.63x as much as the stock outlet. This is a significant difference.
Keep in mind this is a flow bench designed to test NA heads for flow. The CFM reading isn't representative of what it would flow under boost, the purpose of this test was to simply state, outlet A stock when put on a flow bench flows X. Outlet B VTT under the same conditions flows 63% more. This should lay to rest the doubts about performance.
Results Recap:
Stock Outlet: 215.35 CFM @ 28" water
VTT Outlet: 352.23 CFM @ 28" water
Difference: VTT outflows by ~63%
Vids:
Video #1: Stock testing
[video=youtu;V5DDjIwFB9A]
Video #2: VTT Outlet testing
[video=youtu;VA5trZCW9l0]
Video #3: Wrap up
[video=youtu;6PwqwrI6Lu4]
We didn't do anything fancy, as this isn't a fancy test. We ran all tests at 28" of water, which is standard for most flow bench tests. The flow bench they use is an SF-600, which can flow up to 600 CFM. You can read specs about it to your heart's content at this site: http://www.assurich.com.my/engine-dynamometer-system-superflow-sf-600.htm
We began by installing the stock outlet on the bench using a 2.5" silicone adapter and turned the machine on. Dave does A LOT of flow testing, so his guess that "Range 4" was about right was dead on. Range 4 has a maximum flow of 295 CFM at 28" of water. Results showed it flowed right at 73% (of 295 CFM), so the stock outlet flowed 215.4 CFM.
With no setting changes, we pulled the stock outlet off and put on the VTT aluminum outlet. When turning the machine back on, it flowed 100% at 28" of water -out of range (high) on Range 4 and Range 5. Dave laughed and said "you maxed out my flow bench" as he rarely has to use "Range 6". Dave schooled Tony on the topic after testing and explained how if you have ranges left unused, once you hit above 75% you'll always want to go up to the next range and bring the flow percentage down into a more reasonable range for more accurate readings. Range 6 has a maximum flow of 597 CFM at 28" of water. When Dave turned the machine back on, we could see that the VTT outlet flowed 59% (of 597 CFM), so the VTT outlet flowed 352.2 CFM.
The VTT outlet flows 1.63x as much as the stock outlet. This is a significant difference.
Keep in mind this is a flow bench designed to test NA heads for flow. The CFM reading isn't representative of what it would flow under boost, the purpose of this test was to simply state, outlet A stock when put on a flow bench flows X. Outlet B VTT under the same conditions flows 63% more. This should lay to rest the doubts about performance.
Results Recap:
Stock Outlet: 215.35 CFM @ 28" water
VTT Outlet: 352.23 CFM @ 28" water
Difference: VTT outflows by ~63%
Vids:
Video #1: Stock testing
[video=youtu;V5DDjIwFB9A]
Video #2: VTT Outlet testing
[video=youtu;VA5trZCW9l0]
Video #3: Wrap up
[video=youtu;6PwqwrI6Lu4]