And I'll say it again: Divided inlet turbines have been around for decades. You can find T series turbos from the 60's and 70's with this "technology". The Garrett used on the M21 had a divided inlet. Big f-in deal.
That said, I still dont believe they're what you hype them up to be. The dyno chart posted earlier in this thread showed better spool from an undivided turbine.
Lets see a back to back dyno comparison instead of more babbling about transient response. Some actual proof that its measurably better, that would be excellent. I know how its supposed to work in theory, but how does it actually apply to an M20 or M30 engine with a stock cam and at a reasonable boost level? And how do I know the difference between one Holset and another turbo isnt in the divided inlet but because you're comparing turbos of different sizes and specifications?
I'm still not buying it.
I need turbo specs!
It´s not something I´m claiming it´s completely known with all the turbo manufacturers and noted in multiple literature going back decades as you say. And since I can´t reference anything from a book that is not here with me, there isn´t much I can do to "sell" you anything.turbodan wrote:And I'll say it again: Divided inlet turbines have been around for decades. You can find T series turbos from the 60's and 70's with this "technology". The Garrett used on the M21 had a divided inlet. Big f-in deal.
That said, I still dont believe they're what you hype them up to be. The dyno chart posted earlier in this thread showed better spool from an undivided turbine.
Lets see a back to back dyno comparison instead of more babbling about transient response. Some actual proof that its measurably better, that would be excellent. I know how its supposed to work in theory, but how does it actually apply to an M20 or M30 engine with a stock cam and at a reasonable boost level? And how do I know the difference between one Holset and another turbo isnt in the divided inlet but because you're comparing turbos of different sizes and specifications?
I'm still not buying it.
If you don´t want to "keep" up with whats going on in the turbo industry and just wait for garret to start selling it then sure.
Twin scroll TB hsing and mani setups
Here is a thread with a guy using various TS(divided) turbine hsings(different A/R's) and a TS mani setup on the Garrett 30R and 35R. This is for the non believers who refuse to understand that the twinscroll setups(mani and turbine hsing combo) are infact better and more responsive than the single scroll setup. And this guy proves it.
READ:
http://forums.evolutionm.net/showthread.php?t=312126
This also goes for the folks that are using Holset turbos that understand this whole concept. Most newer turbocharged cars are using twinscroll setups as a result.
"The turbine is rarely subjected to constant exhaust pressure. In pulse turbocharged engines, twin-entry turbines allow exhaust gas pulsations to be optimized, because a higher turbine pressure ratio is reached in a shorter time. Thus, through the increasing pressure ratio, the efficiency rises, improving the all-important time interval when a high, more efficient mass flow is passing through the turbine. As a result of this improved exhaust gas energy utilization, the engine's boost pressure characteristics and, hence, torque behavior is improved, particularly at low engine speeds.
To prevent the various cylinders from interfering with each other during the charge exchange cycles, three cylinders are connected into one exhaust gas manifold. Twin-entry turbines then allow the exhaust gas flow to be fed separately through the turbine"
However I am also not trying to get into the discussion as to whether Garrett,BW,or Holset make better turbos,but I sure do know that the Holset can be bought for much cheaper used and is readily available.
READ:
http://forums.evolutionm.net/showthread.php?t=312126
This also goes for the folks that are using Holset turbos that understand this whole concept. Most newer turbocharged cars are using twinscroll setups as a result.
"The turbine is rarely subjected to constant exhaust pressure. In pulse turbocharged engines, twin-entry turbines allow exhaust gas pulsations to be optimized, because a higher turbine pressure ratio is reached in a shorter time. Thus, through the increasing pressure ratio, the efficiency rises, improving the all-important time interval when a high, more efficient mass flow is passing through the turbine. As a result of this improved exhaust gas energy utilization, the engine's boost pressure characteristics and, hence, torque behavior is improved, particularly at low engine speeds.
To prevent the various cylinders from interfering with each other during the charge exchange cycles, three cylinders are connected into one exhaust gas manifold. Twin-entry turbines then allow the exhaust gas flow to be fed separately through the turbine"
However I am also not trying to get into the discussion as to whether Garrett,BW,or Holset make better turbos,but I sure do know that the Holset can be bought for much cheaper used and is readily available.
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Interesting feedback here!
Re: I need turbo specs!
For the money you cant beat the h35 or hx40 for an m30. You can get an hx35 for $150, modify for an external wastegate or spend another couple hundred bucks and get a custom turbine housing. Yes you could get a Garrett and pay for that name but i suggest taking the extra 1k and using it torwards a cam or better non-log manifold
Other benefits to the holset
-made in the usa
-easily rebuilt(factory kit is $60)
-reliable, stupidly
As for the argument of who makes the best turbo, borg warner is way ahead. They offer Titanium Aluminide turbine wheels, half the weight of inconel. As far as i know they are the only ones doing outside of aerospace.
Other benefits to the holset
-made in the usa
-easily rebuilt(factory kit is $60)
-reliable, stupidly
As for the argument of who makes the best turbo, borg warner is way ahead. They offer Titanium Aluminide turbine wheels, half the weight of inconel. As far as i know they are the only ones doing outside of aerospace.
Re: I need turbo specs!
What happened to iXer? he was a true OG 