Adam Connell

Good Morning All!
After seeing the new BMW engine, I got to thinking more about twin scroll turbos.

I have read through Zombie's quick spool valve thread and was also intrigued.

I am having a hard time finding more information on the scroll concept though.


So on a single front mount setup, should each cylinder bank get it's own side of the housing?

In theory, would a 1.0AR split housing act like a .50AR housing or what is the reason for splitting the housing?

If done in a twin turbo setup, would you pair up the cylinders like try y headers?

Also what do you think is the comparison between a twin scroll with the quick spool valve, VS. splitting the cylinders exhaust like I mentioned above?


The reason why I am so intrigued by this is the fact that the BMW gets the grunt of a Roots style blower with the efficiency and power curve of a turbo setup. Zero lag time and brutal low end without choking the engine up top!

If anyone has any reading material on this concept please send links or book names!

3800SII

I have the quickspool valve coming in for my GrandamGT. I have two twinscroll turbos. One is a Master Power and the other is an ebay version

I am going to use the twinscroll on my Grandam GT which has a rear mounted turbo. I am building a front mount turbo for my 3800 Firebird which will have twin wastegates attached and each exhaust bank will feed into one side of the turbo. The turbine AR on the ebay turbo is .82. The AR on the Firebird turbo is .70. In essence, the larger turbine divided by the quickspool valve will spool faster than the normal twin wastegated Masterpower turbo with the smaller AR.

I don't have both systems fully operational, but I plan on providing results on both once complete.

ayousef

I awear to god I had plans on researching this myself, but after looking at the bmw engine, thats an engineering marvel, far beyond what i could think of, and yes it makes 1.5bar of boost on a 4.4liter v8 engine on pump gas, thats 21psi of boost all the way from 1500rpms to a tad below 6000, and max power at 6000, which again is sort of a trick to lower the max HP on paper, yet making low-end and midrange of one big *** motor.

With the exhaust manifolds containing the heat within, its hard to understand how they are eliminating the heat to soak the compressor side of the turbos, and have to work that out and the efficiency of the intercoolers because 1.5bar of boost from 1.5k to 6K will definitely heat up the intake charge big-time, especially the fact that you can be in boost 60% of the time you are driving.

I drive a cayenne turbo as a daily driver, and i can tell you that its really hard to stay off boost even during NORMAL acceleration, those turbos are too small, theyll spool up whether u like it or not lol.

I hope you understand what i say, lets hear somre more feedback on this...