hey does anyone know the actual rpms of the turbo itself. I'm trying to do a project for school (PSU) and I was interested in finding out what kind of rpms a turbo hits at say idle, 4000, and 8000 engine rpm. I realize that they will very greatly from engine to engine and tubo to turbo, just looking for ball park figures (like 10, 100, 1000, 10000rpm, etc).

thanks
Joe

 

it's not going to spin in relation to RPM, it will spin in relation to air flow which is determined by engine load

and it's more like 180,000rpms for the turbo

 

yeah, I was kinda joking about the 10 rpm. Wow 180,000 is very high, I was expecting aroud 100,000 max. Interesting.

 

If you look at compressor maps, RPM of the turbo compressor usually is listed on the map islands outlines. So after you go through the math of figuring out a engines volumetric effiency at certain RPM,s then search and go by others experiance to figured what boost pressures people are getting per engine RPM (loaded, like 4th gear pull) and go back to the compressor map and deduct approximate turbo RPM. Doing all this math is all theoretical and actual real world results vary, but with the above method it should get you in the ball park.

BTW, the smaller the turbo charger, in general the higher RPM's its operating range will be. EX: small t3 40 trim runs a peak of 154,000 RPM were the middle sized 60-1 runs 120,600, to the large T76 will see 95,300 RPM.


~Mike..........

 

I recently saw a turbo tachometer device for sale somewhere. If you are really curious, you could get one of those and do some experiments.

-Max

 

I have a few compressor maps in Excel format from Garrett. Compressor RPM is listed for various pressure/flow rates. PM me your e-mail and I'll reply with a couple.

BTW- GT35R RPMs are ~ 52,000 at 4PSI, 73,000 at 9 PSI, and 98,000 at 20 PSI (at 5K engine RPM and 0 PSI pressure drop). Max for this turbo is listed at 116,000 which happens at about 30PSI!

Gene