Cool, thanks a ton for the fast help. Now I gotta get my oil pressure sender figured out.

I'll report back if the intake manifold port works for me.

 

The only way its going to read significant vacuum is between the throttle plate and the motor
putting it in the charge line is going to be very little vacuum and only boost.
thats the mistake thats being made here.

 

Colin, could you explain that a bit more?

I'm familiar with the N18's setup on vac lines, etc. for my Forge BPV (different setup from the others especially with the R60 N18).

Have you point a tap point (hoses are fine) that will show both correct boost and vac pressures?

 

the way a engine conventionally pulls vacuum is because its trying to draw air against a closed throttle plate.
its the lack of air making it through the throttle plate causes it to "Suck"
Where you are putting it on the upper charge pipe their is no "sucking"
its just measuring the restriction from the filter assembly to that point.
What you need to do is have it on the intake manifold between the throttle and the motor.
However if you put it there and its still not drawing vac its completely possible that the motor just simply is not generating the vac, one way to check it is to plug a obd2 scanner in that can read data and see what the KPA numbers the ecu is producing from the sensors to verify if your gauge is right.
Realistically just having working boost should be enough because watching that will tell you if you are boost cutting,over shooting or having problems maintaining boost pointing to a problem.
Hopefully that helps.

 

I see what you're saying. The fundamental problem was the N18 re-design. Nobody has yet found any lines that supply both vac and boost.

At this point, the best course of action is to use a MAP tap and measure boost. That's more important than measuring vac.

 

drill and tap the intake manifold.
wheres the map, it should be on the intake manifold.
if so thats the right place to do it.
their will be vacuum there, how much. i dont know....

 

What?

There's no need to do that. The intake manifold is only going to show boost on an N18 motor.

 

That's the place. As I mentioned in your other thread, the Craven Psiclone adapter worked perfectly for me.

The pressure at the intake manifold on the N18 will show vacuum for the first few minutes after a cold start. Once the engine has warmed up a bit, the ECU and variable valve timing sets the manifold pressure to 0 (1 atm) and after that all you see is boost with a brief dip below 0 when backing off the throttle suddenly. The Torque app shows exactly the same thing reading the MAP sensor from the ECU. Makes the boost gauge a bit boring.

From studying the diagrams on realoem.com, it looks like vacuum in the N18 is generated by a pump driven off the camshaft for boosting the brakes and controlling the turbo blowoff valve.

 

That's exactly right ^^

 

So that MAP sensor at the intake manifold worked for me. It seems like at idle the gauge reads ~-1psi, is that normal? It seems like it should read 0.

 

Nah, that's pretty normal. Gauge variance plays a part, too. My Autometer reads around .5PSI at idle.

 

Theta, I know I've been badgering you about this via PM. Will I need to tap anything to get a good boost reading on either the UltraGauge or ScanGauge II? The UG portends to tell "boost" directly and the SGII gives me MAP readings.

If at all possible, I'd like to be able get an accurate boost reading at a glance without having to adjust for anything.

Sorry for posing such a novice question.

 

No, you do not have to tap anything to use those sensors. They are working off of the ODB values of Manifold Pressure. For the SG2, take the reading and subtract between 11 and 13 to get an accurate reading.

If you want something dead-on accurate, you need to buy a boost tap, install it, and run the vacuum line into the cabin for a boost gauge.

 

The BSH Boost Tap does work on an N18 engine.

Instead of tapping the hose from the valve cover to the intake manifold on an N14 (2007-2010), plug the Boost Tap directly into the Intake Manifold and place the factory plug (currently installed on the N18's intake manifold) into the back end Boost Tap.

This is a nice reversible way of getting a reading from the intake manifold without having to drill.

 

is that the part #4?

 

Perhaps I'm misunderstanding here (and forgive me if I am)...

But are you saying to use a boost tap at the factory MAP sensor location? If so... we've been doing that for years. On the N18, the MAP tap will not show both boost and vac, that's a proven fact.

If, however, I've missed what you're saying - please clarify.

 

Part #4 is a rubber bushing that is for anti-vibration and rests on the engine.

 

Pictured above is the N14 intake manifold, showing the PCV hose that runs from the valve cover to the intake manifold. The BSH Boost Tap was designed to go on the valve cover side of this hose, using a block off plug to stop the PCV gases from passing through the hose and into the intake manifold. The port that the PCV hose connects to on the intake manifold for the N14 exists on the N18 however with a factory block off plug.

The BSH Boost tap can be used on the N18 intake manifold by installing it directly onto the intake manifold, without the BSH supplied block off plug and then reinstalling the factory block off already installed on the intake manifold.

 

got it, had a quick look on my cms all4

thanks

 

Thanks very much for clarifying - that's an excellent idea! I will buy one of those tomorrow, as the "choose vac or boost" decision has gotten pretty old.

 

Actually, the SG2 now comes with a setting for boost (versus just MAP, which is the default). Changing this setting (as I understand it) to "Boost", does the subtraction for you and shows vacuum as well.

 

Hmm, the new one they sent me specifically for MINI 2010+ doesn't have a Boost setting (it does have MAP and the new EOT and ENG readings).

That being said, i still prefer a mechanical gauge for the speed factor!

 

I can't figure out how to get a boost reading on my SGII, either. But my UltraGauge does give me a straight boost/vacuum reading separate and apart from MAP and therefore without having to convert.

Makes it tough to decide which gauge to go with!

Now if only I could get a reading for EGTs.

 

AZblackOUT,

I took your advice and ordered a BSH tap - I'll try it out as you described.

Have you had any issues running it on your R60?

 

did this work?