BP4W flow rate
#23
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<p>Sorry for the delay. Here's some flow bench data. The head is a 1999 BP4W. Flow bench done at stock and after a mild port and polish job done on the same cylinder of the same head. I had 1 cylinder with a noticable core shift on the exhaust side but all the other ports seemed to have minial core shift. I think the core shift was on cylinder 4 and I flowed cylinder 1.</p><p>For the port job I tried to follow Mike Keegan's advice in this edmund article shown below. Minimal enlarging of the intake port was done. The short side radius was cleaned up, bowl transition smoothed out and casting surface polished. The exchaust side I did a mild port enlargment focusing on the roof and the same throat details mentioned above. I have no installed or dyno'd any HP changes due to this port job.</p><p>Keegan Engineering Head And Porting Tech - 1997 Mazda MX-5 Miata Long-Term Road Test</p><p> </p><p> </p><p><img src="http://cimg3.ibsrv.net/gimg/www.miataturbo.net-vbulletin/926x563/80-graph_2_9b74f193b879f29dae9e30ff6d49249858a2ca9e.j pg" title="" /><br /><br /><br /><br /><img src="http://cimg1.ibsrv.net/gimg/www.miataturbo.net-vbulletin/1023x684/80-table_0c69e034bbf344a28794761f8f04c9011633ca7b.jpg " title="" /><br /> </p>
#28
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<p>Sorry for the delay. Here's some flow bench data. The head is a 1999 BP4W. Flow bench done at stock and after a mild port and polish job done on the same cylinder of the same head. I had 1 cylinder with a noticable core shift on the exhaust side but all the other ports seemed to have minial core shift. I think the core shift was on cylinder 4 and I flowed cylinder 1.</p><p>For the port job I tried to follow Mike Keegan's advice in this edmund article shown below. Minimal enlarging of the intake port was done. The short side radius was cleaned up, bowl transition smoothed out and casting surface polished. The exchaust side I did a mild port enlargment focusing on the roof and the same throat details mentioned above. I have no installed or dyno'd any HP changes due to this port job.</p><p>Keegan Engineering Head And Porting Tech - 1997 Mazda MX-5 Miata Long-Term Road Test</p>
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