what are the advantages and disadvantages of ball bearing vs twin scroll... i think the twin scroll would spool up faster? im stuck between a HKS 2835... 3037... and now the AMS turbo not looking 2 bad..it is my daily driver... so i do kind of want a turbo that would spool pretty fast.. i kno the 3037 is kinda laggy... but the 2835 supposbly only makes around 300 or so around 19psi... which is weak to me =X advice would b appreciated

 

Simply put, twin scroll allows for two "jets" of exhaust to be divided up seperatly and scroll the turbo up faster. This happens because there is no interference between the exhaust turbulence between different pistons. So the twin scroll allows for better boost response out of a larger turbo. Ball bearing turbos have ball bearings in the cartridge, and that allows for less rolling resistance of the turbo assembly. Again this is done to reduce lag. Some turbos use roller bearings, which are not as good as ball bearings. Also, twin scroll turbos are rare, and more exotic. They also need a special manifold as well as turbine wheel design. Ball bearing turbos are a dime a dozen in that they are very common, and have been around for a while. Twin scroll turbos are hard to find, so most people when they upgrade thier EVO are forced to lose the advantages of the twin scroll design. If anyone had the option, they would take a turbo upgrade with the ability to keep the twin scroll design. Of course this isn't an option. Also, if you look at the boost maps for an EVO compared to a WRX, you will see that even though the WRX has a much smaller turbo, the EVO spools a lottle faster. Also, if someone tries a turbo upgrade on a WRX and gets the same power as an EVO, they will not have as sharp of boost response as the EVO does. Just my .02

 

Just to clear up some misconeceptions I see alot on this, and other boards:

1. the 2835 by itself really tells you very little...the wheels are what matter. There are a variety of wheel trims and exhaust housings that can be used with the 2835 turbo, and those will determine not only how much peak power can be supported (how much you achieve is a whole other ballgame), and where that power will come in.

2. twin scroll and ball bearing are often as much marketing jargon as they are technical terms....one is not better than another, just different. Plenty of us out there make gobs of power on a variety of cars without ball bearing turbos, and without twin scroll setups....don't make your purchase based on these factors, as again, the wheel trims, and housing A/R's really make a much bigger difference overall.

3. The WRX tends to spool slower due to its manifold design, and as a result, its turbo placement. Your net results with a WRX are almost entirely dependant on how it is tuned, which is true with any car out there.

Hope that helps you some!

Adam

 

are there any twin scrolls that you can get larger? Can you get a 20G twin scroll?

-Shahul

 

can u get about the same size as a 3037 twin scroll??? that extra spool up time would help me out A LOT on the streets.... garret makes twin scroll am i not correct?
is it possible to have a ball bearing twin scroll turbocharger? if there isnt one... could i get one custom made by someone like garret... turbo xs or someone?

 

i called AMS earlier today and found out that their turbo is twin scroll... and should spool faster than the ball bearin 3037 kit and make the same amount of power... if this is the case... y wouldnt everyone that plans on gettin the 3037 buy the AMS turbo kit?

 

bump

 

To compare twin scroll to ball bearing is not really a fair comparison. Twin scroll is simply an exhaust housing design versus ball bearings which is what the shaft rides on, apples to oranges comparison. Like Adam at Z1 said, there are many much more important factors in choosing a turbo for you specific application. Personally I don't beleive in selling the vast majority of my customers ball bearing turbos. We have plenty of turbos that will spool up just as fast as a BB turbo due to newer exhaust housing develeopements, that cost a ton less money.

-kris

 

Do the stock Mitsu turbos contain ball bearings? How are the moving parts separated from the housing?

 

No ball bearings. The center cartridge rides insode the compressor and exhaust housings. For the average person, the center section is a sealed unit and the housings are clamped to it.

Download the Tech Manual for this car or go to www.dsm.org and learn everything you want to know about the 4G63 variants and the turbos that have been commonly used on them.


Josh