Boost Gauge Hook Up

[metros]

I'm working on installing my Spa Dual Gauges. The boost sensor has 1/8 NPT threads. Best plan of installation would probably be to tap the manifold for 1/8 npt and screw in. However, I have the manifold installed and don't want to worry about shavings getting into the intake tract. Second best option 1/8 NPT to hose barb adapter? Or is there a better choice?

[mikeb75]

Hose barb fitting -> BPV/bypass valve hose. Pretty sure that's the most common installation.

[Aero STI]

Yeah, put a T on the BPV line and connect this to that T.

[Scargo]

Going from 10mm x 1.0T (tapered) thread to 1/8" NPT is a baby step. JIS (Japanese Industrial Standard) has a 2° difference in taper from US Standard but with the exact same thread pitch. You would hardly be cutting threads...
No drilling required! You could do a countersink for the o-ring. Mine don't have that. It's odd that it is 1/8"NPT and has an o-ring. You sure it's tapered or NPT?

I suggest that you grease the tap and remove and clean it often and that you will find that the chips are minimal to get it to fit. Don't be scared. I've done it many times. I had a sensor/transducer dangling for a while and I prefer a cleaner, more direct, raceworthy approach. Plus, it's potentially grounded.

Glad to see others using SPA gauges. I have two dual gauges in my STi. I like the gauges and their programmable outputs. You could use your boost gauge to activate a second fuel pump, nitrous, etc.

[STiPWRD]

+1 on the 1/8 npt female barb fitting to anywhere on the intake manifold. I removed by emissions system so I hooked my boost gauge to the barb where the purge control solenoid used to be (front of the IM near the turbo inlet tube).

[ssssly]

There are several casting blanks on the intake manifold that you could drill out and tap. If the manifold is on the car, definitely take scargo's tip and hand drill and tap with a bunch of grease to catch the shavings.

[Scargo]

You are showing us a UK spec transducer, right?
Attachment 54398
I don't see a description of the threads but I'm guessing they are straight threads, probably Metric.

[metros]

All of the other threads on my spa sensors were 1/8 npt, so I assumed this was as well.

I think for the time being I'll use a barb and vacuum line. I can always tap the manifold the next time I have it off.

[Sgt.Gator]

Not really related to boost taps but FYI for all since we are talking about NPT taps: The threaded fittings on a Subaru block that look like 1/8 NPT are not, the are BSPT. The specs are extremely close but not the same. Guys screw NPT fittings into them all the time, that works once or twice, but you're screwing up the block threads. I discovered this reading a thread on the LGT forum about building a pre-startup - pre-oiling system. Basically a home depot garden sprayer filled with oil that you attach to the block to fill a newly built engine oil passages. The 1//8" BSPT fittings are very uncommon in the US but I have a few 1/8" BSPT to 1/4" hose barb fittings left because I had to buy 10 to get one.

NASIOC thread on the BSPT : NPT: http://forums.nasioc.com/forums/showthread.php?t=366112

LGT thread on the Pre-Oiler: http://legacygt.com/forums/showthrea...nk-214760.html

And more info on the difference between NPT and BSPT: http://www.ralstoninst.com/news/stor...nd-bspt-seals/

[Scargo]

I would guess that what you have is a M10 X 1 DIN fitting on the end of the transducer. If correct, you will need an adapter so the o-ring has a seat to compress into. You could tap the hole and use a 45 degree countersink. You could also substitute a crush washer for mating against a flat surface.
Doesn't the information that came with the gauge tell you anything?
din sizes.jpg