hi
i just got a new SPA digital boost/fuel preasure guage and in the manual it says to place the preasure sensor in the intake elbow, is this right or should i put it before the intercooler like my boost controller.
regards
chris
For the boost reading there is already a nipple available on the UIM (the big shiney funny shaped ali thing on the top of the engine. Just take your reading from here, this is where essentially everyone plumbs their boost gauges.
HTH,
Alex.
the sensor is a screw in one though so ill have to thread it to fit.
regards
chris
Hmm, so do you have a mechanical gauge?!
ie, does this threaded thing have a vacuum pipe (hollow rubber pipe) going to the gauge.
or, an electric gause?!
ie, does the sender take the vacuum reading and then pass it to the gauge via a piece of electrical wire?
If it\'s mechanical you can probably just take off the threaded bit, and plumb your gauge straight into the nipple.
If it\'s electrical you might want to plumb a pipe from the UIM to the sender in some way. Or..... drill a hole in your elbow. The elbow in the car obviosly!
The majority of people here use mechanical gauges with a pressure hose going into the cabin, and plumbing directly into the gauge. Simple and accurate. I\'m sure we can make what you\'ve got work though. You could post a picture, or a link to what you have, and we\'ll go from there.
Alex.
its fully electrical, i wanted a digital fuel pressure guage and saw this combined unit.
these are professional motorsport guages and very accurate, not cheap though £238 but cheaper than buying two seperate jap ones.
so do i drill n tap my greddy elbow or the uim
you want it as close to the rotor as possible so you get the boost that the engine is seeing, rather than what the boost circuit is seeing, if you place it before the throttle butterfly then on half throttle you\'ll see more boost then on full throttle because of the restriction in the throttle.
BTW those guages are very good, did you get that from demon-tweeks ? I\'d say tap the UIM, thats just my 2p worth
OK, Nice gauges BTW. Very pro !!!
You have a few options here...
1) Drill/tap the elbow (although you will get odd part-throttle readings)
2) Drill/tap the UIM (good readings, but you\'re making a non-reversable mod)
3) Take a rubber feed from the existing UIM nipple and plumb into your sender.
Personally I would do 3) ... You can reverse the mod, you can keep your gauges when you sell the car and just plug the nipple as normal. There are numberous places on the firewall to mount the sender, then run a piece of rubber tubing from the UIM nipple to the thread on the sender (secure with a zip-tie for safety).
As for the fuel-pressure sender, I assume you have something in mind already for this?
Alex.
gotta agree with smifta reversible mods are always sensible, if you can get some silicone vacuum hose that\'ll fit over the thread then try that, if not, try and find out the thread depth and pitch of the thread and get an adapter to take silicone hose, demon-tweeks will sell these, i had the same problem with a mocal boost guage
Or get hold of a 2nd hand UIM to use in the event of there being a problem.