Blog — borg warner

Courtesy of www.TurbobyGarrett.com A/R (Area/Radius) describes a geometric characteristic of all compressor and turbine housings. Technically, it is defined as: the inlet (or, for compressor housings, the discharge) cross-sectional area divided by the radius from the turbo centerline to the centroid of that area (see Figure 2.). Figure 2. Illustration of compressor housing showing A/R characteristic   The A/R parameter has different effects on the compressor and turbine performance, as outlined below. Compressor A/R - Compressor performance is comparatively insensitive to changes in A/R. Larger A/R housings are sometimes used to optimize performance of low boost applications, and smaller A/R...

Courtesy of www.TurbobyGarrett.com Getting a little more complex here. Trim is a common term used when talking about or describing turbochargers. For example, you may hear someone say "I have a GT2871R 56 Trim turbocharger". What is 'Trim?' Trim is a term to express the relationship between the inducer* and exducer* of both turbine and compressor wheels. More accurately, it is an area ratio. * The inducer diameter is defined as the diameter where the air enters the wheel, whereas the exducer diameter is defined as the diameter where the air exits the wheel. Based on aerodynamics and air entry...

Courtesy of www.TurbobyGarrett.com On the exhaust side, a Wastegate provides us a means to control the boost pressure of the engine. Some commercial diesel applications do not use Wastegates at all. This type of system is called a free-floating turbocharger. However, the vast majority of gasoline performance applications require a Wastegate. There are two (2) configurations of Wastegates, internal or external. Both internal and external Wastegates provide a means to bypass exhaust flow from the turbine wheel. Bypassing this energy (e.g. exhaust flow) reduces the power driving the turbine wheel to match the power required for a given boost level....

Courtesy of www.TurbobyGarrett.com. The journal bearing has long been the brawn of the turbocharger, however a ball-bearing cartridge is now an affordable technology advancement that provides significant performance improvements to the turbocharger. Ball bearing innovation began as a result of work with the Garrett Motorsports group for several racing series where it received the term the ‘cartridge ball bearing’. The cartridge is a single sleeve system that contains a set of angular contact ball bearings on either end, whereas the traditional bearing system contains a set of journal bearings and a thrust bearing Journal Bearings Ball Bearings Turbo Response –...

So this is a Blog right? Then I might as well rant a bit. Over the years I have been pretty opinionated over rules, trends, and the general direction of Sport Compact Drag Racing. I have to give credit where credit is due and that is to the organizers and promoters that put these events on. That is a heck of a lot of work that I know is extraordinarily hard to get done and keep everyone happy. I know that that is not a venture that I ever want get involved in as I see what the current organizers...