Why aren't we installing knife edged cranks, 2300bar commonrail system with piezo injectors, CP4.x pumps... You make do with what you've got - you spend the money where it counts. The best turbochargers will make up for any lacking in the manifold department - if we find that EMPs are up through the roof at high RPM and mass flow rate not increasing, we'll know there's an issue.
I know the "efficiency" thing is pretty much dig at me... From my experience people discuss things they don't understand and take the word "efficiency" well out of context because "I did this and look at the dyno figures"... Take a leaf out the OEMs book - x35d uses a log manifold with a 4+2 design, 3.0 V6 TDi uses two log manifolds with a link pipe! Worst design going by what you'd read on the internet! Yeah, >400HP isn't a problem with an upgraded compressor wheel/turbo... OEMs _still_ use log manifolds on their highest performing diesels without any problems. I'm not going to deny that a better design wouldn't be better, however in the grand scheme of things, there's other problem areas that you'd work on first before worrying about exhaust manifold design.
I know the "efficiency" thing is pretty much dig at me... From my experience people discuss things they don't understand and take the word "efficiency" well out of context because "I did this and look at the dyno figures"... Take a leaf out the OEMs book - x35d uses a log manifold with a 4+2 design, 3.0 V6 TDi uses two log manifolds with a link pipe! Worst design going by what you'd read on the internet! Yeah, >400HP isn't a problem with an upgraded compressor wheel/turbo... OEMs _still_ use log manifolds on their highest performing diesels without any problems. I'm not going to deny that a better design wouldn't be better, however in the grand scheme of things, there's other problem areas that you'd work on first before worrying about exhaust manifold design.
