Hi guys I was wondering how the Borg warner efr 7064 turbo would compare to the other more common single turbo out there like the t04z,gt35r,t67,t88.

Cause it would be nice to see a Borg warner on a rotary I think it would work because it has about the same max flow rate as a rx7 (between 50 to 60) and you wouldn't have to raise your boost level to a ridiculous amount so feel free to inquire your thoughts





Here is the url to the turbo I'm talking about

http://www.full-race.com/store/turbo...064-turbo.html

 

It doesnīt work that way.



Flow is purely dependent on volumetric efficiency of whole system and pressure ratio. And pressure ratio - boost, isnīt cause but consequence of flow. Turbocharger of your interest can flow 56 Lb/min of air, but to be in efficiency island of 60%, pressure ratio would have to be atleast 3.5 which is over 37 psi boost.

This turbo has compressor inducer of 52.2 mm, GT35R is much larger, inducer of 61 mm. Consequently GT35R can flow the same amount at much lower pressure ratio.





These turbochargers are implementing quite interesting features, but to utilize higher flow rate against "ordinary" turbochargers, you have to boost it.

 

Ah I see now cause I get the basic idea just not all the tech figures and what not and and 37 psi is just redicoulous



thanks for clearing up unsolved questions of my imaganation

 

No problem at all. Turbo sizing is really interesting topic, unfortunately, not much examined in rotary comunity. Most people go with above mentioned turbochargers, but why they choose so when they arenīt utilizing compressor properly is beyond me and their mind also obviously



Generaly speeking, rotary flows a lot of air at relatively low pressure ratio and to utilize rev range of rotary, compressor map must be wide, at given boost. Turbine sizing is beyond most people, so again, they go by recommendation, which usually canīt match their intended use



I really like this software from BorgWarner.

MatchBot





You can estimate some numbers, like VE%, A/F ratio, BSFC and it will give you interesting outputs, both on compressor output and turbine input. These numbers, of course can have significant impact on what we previously typed in inputs Like delta pressure between intake absolute pressure and exhaust absolute pressure - it will change VE%, consequently airflow etc....

Its really interesting and can help understand whats really going on in turbo system