The 7 speed manual seems to be a "complex workaround" to be able to meet emission and fuel consumption standards without having to tone down the engine output or gear it weirdly.
I find the 3-turbo-setup odd as well, but after seeing a revival of twin-turbo-setups, it was just a question of time. And thinking that the term "turbo" sort of is connected to the 911 turbo, it makes sense that Porsche would be the manufacturer to come up with it.
Last edited by the Interceptor; February 3rd, 2012 at 11:37 AM.____________________________
Color me typical, but I'd much rather have the fire breathing normally aspirated 500bhp 4.0 RS engine.
This says it all
N/a FTW
Last edited by Eunos_Cosmo; February 3rd, 2012 at 1:30 PM.____________________________
The Metzger engines are very cool.
Something is wrong with me...for the first time, I'm finding a 911 attractive. Damn.
It's okay. Renegade Hybrids has an LS1 swap kit for the 996. You can have your cake and eat it too.Originally Posted by Bad Bowtie
Your hipster glasses are showing...but seriously nice engineColor me typical, but I'd much rather have the fire breathing normally aspirated 500bhp 4.0 RS engine.
This says it all
N/a FTW
I believe the optimum number of cylinders for one turbo to get the best flow is two and if you use a twin-scroll turbo it's four. So for a six cylinder engine you achieve the best result by using 3 ordinary turbos.http://www.************/2010/01/02/tw...ign-explained/
Twin-scroll turbo system design addresses many of the shortcomings of single-scroll turbo systems by separating those cylinders whose exhaust gas pulses interfere with each other. Similar in concept to pairing cylinders on race headers for normally aspirated engines, twin-scroll design pairs cylinders to one side of the turbine inlet such that the kinetic energy from the exhaust gases is recovered more efficiently by the turbine. For example, if a four-cylinder engine’s firing sequence is 1-3-4-2, cylinder 1 is ending its expansion stroke and opening its exhaust valves while cylinder 2 still has its exhaust valves open (while in its overlap period, where both the intake and exhaust valves are partially open at the same time). In a single-scroll or undivided manifold, the exhaust gas pressure pulse from cylinder 1 is therefore going to interfere with cylinder 2′s ability to expel its exhaust gases, rather than delivering it undisturbed to the turbo’s turbine the way a twin-scroll system allows.
The result of the superior scavenging effect from a twin-scroll design is better pressure distribution in the exhaust ports and more efficient delivery of exhaust gas energy to the turbocharger’s turbine. This in turn allows greater valve overlap, resulting in an improved quality and quantity of the air charge entering each cylinder. In fact, with more valve overlap, the scavenging effect of the exhaust flow can literally draw more air in on the intake side while drawing out the last of the low-pressure exhaust gases, helping pack each cylinder with a denser and purer air charge. And as we all know, a denser and purer air charge means stronger combustion and more power, and more power is good!
But the benefits of twin-scroll design don’t end there. With its greater volumetric efficiency and stronger scavenging effect, higher ignition delay can be used, which helps keep peak temperature in the cylinders down. Since cooler cylinder temperatures and lower exhaust gas temperatures allows for a leaner air/fuel ratio, twin-scroll turbo design has been shown to increase turbine efficiency by 7-8 percent and result in fuel efficiency improvements as high as 5 percent.
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