My apologies in advance...I'm sure that this has been discussed before.

Preface:
Ok - So I've done a bit of Googling on the subject of vacuum pressure @ cold & warm idle. Specifically Mini R53. Although reports on vacuum vary greatly from -12 - -22 in-hg.
My Mini S idles and runs great. It is modestly modded: 15% SC pulley, 380cc Deka Seimens injectors, NGK colder plugs & wires, Modified stock CAI box, K&N cone filter, stock Crank pulley.

The short version:
I recently installed a low budget (Actron "Bosch") boost gauge in my (89k mi), pre-facelift '04 R53. I ran 1/8" ID silicone tubing. No kinks or leaks. However, the inexpensive gauge's needle tends to stick.
At cold idle; the needle will drop to -10. If I tap the gauge it will drop to -12. At warm operating temps @ idle; the needle will sit at -8. It's a crappy gauge. I know. What should the normal vacuum pressure be at cold and warm idle?

Side notes:
I managed to free up the sticky needle by intermittently, blowing low pressure compressed air into the back inlet of the gauge and a little WD40. This seems to have worked for the + boost reading. The boost pressure/needle seems to be reading accurately (?) = +12 / +13 PSI @5,800 RPMs (2nd/3rd gear). I am slightly N of sea level.

Anyone have any clever Ideas (besides buying another gauge), of how I can create vacuum suction to perhaps free up the sticky needle in the - in-hg side of the dial? I'm trying to get by for now avoiding sticking a probe in the back of the gauge to disrupt the coil anymore than necessary.
I would like to eventually upgrade to better gauges when finances will allow.

Thanks

Edited:: 5.30.2022 Had a great opportunity to let the Mini loose out in the wild. It is Memorial day. Traffic was even lighter than during the pandemic, WOT in 5th, 5k+ RPMs @ +12 PSI boost = a little over 100+ mph (?)...' was watching the road not so much the speedo
Still now only measuring -12 - -9 in-hg on the vacuum side @ cold or warm idle/off the pedal.

 

Seems to me, mechanical gauges of questionable accuracy defeat objectives of monitoring what's going on in the charge stream. By that, the vacuum line locational placement, avoiding restrictions plus the gauge itself including the needle mechanism. My recent testing with an OBD dongle connected "real time" by bluetooth to Android (or iOS) device seems avoids those issues, since data is drawn directly from the ECU/ECM. OTOH, that does require keeping the dongle inserted in the OBD port. IMO, it would be interesting to monitor and compare boost readings between that mechanical gauge and something like I'm currently using.

 

At warm idle mine sits at -17 in hg

Boost gauge is such a simple device, if your needle is sticking badly then perhaps it's simply a defective unit.

If you bought it new, you should return it in exchange for another one.

Otherwise,
one thing you could try is installing a restrictor,
like this:

Some people also use a fancier version dampner made out of metal, but both basically do the same thing, they are usually fitted to prevent needle flutter, or buzzing sounds.

 

Well... I managed to free the needle ("stick point"), to also clock smoothly in the "-"(negative) vacuum direction of the gauge.
My improvised solution to suck/create vacuum was simply to cut a piece of 1/8" silicone vacuum line: Attach one end to the back inlet of the boost gauge, the other end to a large syringe (transmission fluid filler) and draw 18 in-hg of vacuum. I did this several times and the needle now moves freely past the "stick point". I now get a vacuum reading between -15 & -12 at idle. The needle also continues to clock smoothly in the boost direction. When the engine is turned off the needle rests @ the "0" mark

 

Hey - Thanks for that @Oldboy Speedwell !
I really do prefer having physical gauges in plain view. However, I'll admit; it only makes sense to have good quality reliable gauges to begin with.
The gauge was brand new sealed.and to your point - 'most likely defective'. Despite me really hate having to return stuff. The gauge was cheap enough that it piqued my curiosity to try and "fix it".
Thanks for the insight and link to the restricor!

Oil & Boost gauges installed. Fabricated my own aluminum mounting bracket and ABS gauge pucks.

 

Good work fixing the gauge. Despite being cheap, the gauges look great. It's impressive that you fabricated the mounting bits. Did you create a writeup for that?

 

Thanks for compliment!
I saw a picture on the Alta site(?) a couple of years ago and really liked how the set up looked... but a bit $$. 2months ago, (after revisiting the notion), I finally got around to figuring out how and what materials I wanted to fab and mount it out of . The mount cost me under $4 in materials.
I didn't do a DIY write up...BUT I did take pictures of how and what I used.
I"ll upload the images and post them up in this thread, with a brief write-up.

 

^^^ Also meant to comment on how nice those gauges look! Mine having chrono, no need for oil pressure but then, no convenient place to mount a boost gauge either. I'm curious why MINI engineers didn't provide one within the standard "S" instrument cluster. Supposing the bean counters axed that. Looking forward to your install pics...

 

Years ago I really wanted to upgrade to the dual Chrono Pack but it seemed a bit expensive and probably too intensive for my novice, techie skill level.
What I really wanted were easy to read "old school" gauges right in front of me. I later came across an image of an Alta gauge pod kit flanking the tach / mounted to the steering column. I was sold!....Except for the price.
Seemed like a simple enough concept so I decided to fab my own.

I didn't really have plans to do a DIY write-up on how I and why I decided to create my own gauge mount. So I didn't take many pics.

Here's what I have...FWIW....

Once I picked out my gauges; I kept my eye out for any kind of cylinder that might be the right size to hold/sleeve over the body of the gauges.
A few weeks later I came across a couple of cans of industrial grade expanding foam sealant (aka "great stuff") at a construction site dumpster.

The caps were a perfect fit! = 2-1/8" ID x 2" deep.


The Polypropylene caps were pretty sturdy.
After cutting off the tabs, scuffed them w/220, painted with black plastic paint and Dremeled a 5/16" hole in the bottom/"back" to run the inlet tubing and bulb wires.

At my leisure; I picked up a 1/2"w x 4' length of aluminum flat stock at a local hardware store (Home Depot) = $4+change.
*Note: Use a 1" aluminum flat stock instead...Details below....


I went out to the Mini with the flat stock; eyeballed, measured and made some mild registration bends. After taking some mental notes I cut the aluminum to length.
Made some conforming bends (from my mental notes) with a couple of pair of pliers and vice grips.
* Note: I cushioned the teeth of the pliers with a small piece of folded fabric to avoid leaving tool marks. Both ends of the aluminum stock were then shaped circular (to hold the cap/gauge cups), by wrapping them around a spray paint can. Then formed a bit smaller until it conformed to the size of the caps/gauge cups. At the excess ends, I bent a 90° "clamping tab" and drilled a 3/32" hole for a #6 x 1/4" L machine screw and nut to clamp the cup in place.
**Note: the eccentric tabs in the center span of the bracket (held in with black screws), was an after thought, when I realized the 1/2" stock was not wide enough to drill the holes that would line up with the Tach mount bolt holes.
* 1" flat stock would have been wide enough to work perfectly!


Pictured above is the kitchen counter set up.
I didn't take photos of the installation process. There should be a few instructionals and youtube videos to guide one through routing the hoses and connections from the engine bay up through the steering column.
But I will say, that you will need longer bolts/screws to replace the factory ones that bolt the Tach to the steering column. About a 1/4" - 3/8" longer - If I recall correctly.



Somethings to seriously consider....
On a side note, Regarding the tubing routing/installation: #1- I refuse to use nylon tubing.
Especially for the Oil Pressure gauge and connections. I always use 1/8" copper. #2- I preferred not to use the cheap nylon vacuum tubing that came with the Boost gauge kit (see the nylon kinked connected to the brass fitting in the image? = GARBAGE!).
I opted for 1/8" ID silicone tubing: (pictured in the upper right corner in the image above) - 6' Length snaked from the intake manifold all the way up through the dash at the steering column. At the Boost gauge inlet; I improvised the connection with a 1/8" diam aluminum tubing (I was out of copper). The Boost gauge was mounted to the right of (facing) the Tach. Clearance to the right of the Tach and the dash is a limited/tight tolerance between the back of the gauge pod and the dash. I had to make a slight "S" bend in the aluminum tube to jog around the corner of the dash edge to align with the inlet connection at the bottom of the Boost gauge. *In order to finesse a nice smooth "S" bend in the 1/8" aluminum (or copper) tubing; I fed a small braided stainless steel cable through the tube which prevented the tube from crimping, crushing or deforming while using pliers to form the curves. The remaining end of the aluminum tube was then cut to length and slid in super snugly into (approx 2") the silicone tubing protruding out from the grommet behind the steering column. Insuring it will never have a kink at this junction. The provided brass securing nut and compression sleeve slid on perfectly over the aluminum tube and proved to be a tight leak free connection to the gauge .



Done......?

 

Thanks @MCS4FUN
In hindsight it seemed like alot of work just to mount these cheap a$$ gauges.
I will spare the you and the readers what a costly ordeal it was just to configure the brass 3way fittings for the remote Oil Pressure Gauge & factory Sending switch combo.
I do like the way they look and everything eventually worked out.

 

One more data point for you. My gauge reads -16 @ warm idle. Max boost recorded is 18, at track events.

 

Damn! = 18PSI boost?
What sort of mods do you have? - The most boost I've been able to pull so far is +13. I will say; Although I admit, I don't think I've ever planted the pedal to the floor...but close enough .
The comments posted regarding the "- in hg" vacuum have me a bit perplexed. At idle I'm still only drawing -13 to -10 cold & -9 warm/operating temp. Tapping the gauge as before, no longer jogs the needle.

 

I don't hit 18 often, but when I'm WOT on the uphill at Lime Rock is where I get max boost, I think. I have a 15% reduction pulley, upgraded intercooler, and the car is chipped. Of course, the CAI and Milltek exhaust allow the car to breathe more fully, which always helps performance.

 

As previously outlined in this thread; Although having some inaccurate reading issues with the inexpensive Actron Boost gauge, I felt confident in my routing and connection of the vacuum lines were perfect.
While reading a thread here on NAM - Where does his go under the IC??? , Thanks to @BlwnAway post, I remembered noticing the small hose of my fuel re-circulation EVAP line was kinked during the installation...
but forgot to address/replace the hose with a new one at the same time.

I Removed the intercooler this morning, to make the the re-circulation EVAP hose repair/replace. What I immediately discovered was the **Dorman "T" connection I used for the Boost vacuum line had snapped!
It now makes sense why my vacuum/-in.hg read so high at idle and boost was on the low +end. (sorry no repair pics).


Above are the broken/failed connections.
I replaced the "T" connection for the Boost along with replacing the re-circulation vacuum EVAP hose and rubber coupler with a new one.



I also decided to replace the 1/8" aluminum tube with brass which I connected to the gauge inlet.



Everything tight and leak free -The Boost gauge now reads the correct values = -20in.hg cold, -16in.hg warm idle. +13/+16 Boost @5,800 RPMs.



**Avoid the Dorman Vacuum Connectors at all cost! TRUST ME.

**My initial impression regarding the Dorman multi pak vacuum connectors is that they seemed awfully brittle. Like they were made via old (resin & powder) 3D printer material that was once used and could potentially break/fail.
My instincts were right.

Edit: I O'Reily Auto parts has the 1/8" black plastic (polypropylene?) 'T" vacuum connectors. On my way there now. I will fix it right tomorrow.
Boost on!

 

Yeah, what he said in bold.

Plus -
Be careful... I live in California. Since the gauge was NOT from the factory, it's not allowed to be connected to ANY part of ANY "emission's" equipment. If like in my instance, the first smog test shop that I went to, the guy was VERY knowledgeable. I removed everything, and was passed without problem at the second shop.. Took about 10 minutes to put the gauge back in place and reconnect the line.

Your state "may" be similar..!

Mike

 

Agreed w/the above.
Although I don't think the "deep south" has caught up to CA emissions standards - I suspect that it may in the coming years.
When I lived in FL; If I'm not mistaken, I think the emissions requirements were different between Miami and Tampa (I could be wrong).

Notwithstanding:
A trip down memory lane...
When I moved to LA back in the mid 80s' in my 1967, highly modified, 105hp Porsche powered VW beetle - I had no trouble passing CA emission laws at that time. Today = NWIH!
Long story short: My beetle was totaled by an AT&T truck/driver who ran a red light.
I bought a bone stock, 40hp, 1967 VW bus (Transporter). I drove all over LA to have that bus emission certified. I went to at least 5 emissions stations who refused/could not pass me.
Some attendants even eluded to; quote: "I can pass you...for $100"
I finally implored the DMV to empathize with my dilemma. Their response was; quote: "Oh, Your 1967 is grandfathered in. You are not required for the emissions."

True story.