Manifold vacuum at idle on RB25/26?

[Torques]

Would anybody know what their manifold vacuum (mmHG) at idle is?

Thanks

[GTSBoy]

It's generally ~ -20 inHg.  That sort of territory.  Depends on the health of the motor, cams and idle speed.  My boost controller reports -9.9 psi (which is the end of the -ve scale) at a good idle, ranging up to ~ -9 when it's idling faster or venting the carbon canister, etc.

[Torques]

Thanks for that ... mine is about 470mmHG (idle/ 77C) which is 18.5inHG.

I'm running (RB25DET) slightly higher idle/timing (850/20) because of my poncams and OS GIKEN clutch (light flywheel) and was wondering what the vacuum on other cars is.

So I guess that's in the ballpark.

 

[MrRx7s3]

What about the NEO?

[Wolfiewolfie]

-16 to -18 in my RB25DET Neo. Before putting my front mount intercooler in it was around -20

Edited February 24, 2019 by Wolfiewolfie