Boost gauges

azn2nr · Post by **azn2nr** » Thu Nov 17, 2005 7:22 am

you shouldnt need to remove the studs for the cup. that black plastic thingie, i have no idea what its for but you shouldnt need it.

also i strongly recomend using as little of the white hardline as possible and using a rubber line form the autoparts store that fits snug over it and matching "t"'s for tapping the line

ultrasonic · Post by **ultrasonic** » Thu Nov 17, 2005 9:00 am

Legacy777 wrote:Got my gauge today....and autometer forgot to put the bulb and bulb holder in the damn gauge.....I was like WTF??

So Summit is supposed to be sending me just that piece.

Here's some pics. Is there anything else that I'm missing? I'm also assuming I need to remove the long studs from the gauge in order to install it in the cup.
http://www.main.experiencetherave.com:8 ... oostgauge/

That's a pain in the ass about the light. I'm glad Summit is taking care of you on that. If I remember correctly, I think I cut those long studs to fit the gauge in the cup. I believe I used a cut off wheel on a Dremel.

azn2nr wrote:you shouldnt need to remove the studs for the cup. that black plastic thingie, i have no idea what its for but you shouldnt need it.

also i strongly recomend using as little of the white hardline as possible and using a rubber line form the autoparts store that fits snug over it and matching "t"'s for tapping the line

The black thing in the 6155 picture is for mounting the gauge in a panel. Not needed for this installation.

I used vacuum line instead of the small plastic hose supplied with the gauge.

gt2.5turbo · Post by **gt2.5turbo** » Thu Nov 17, 2005 10:27 am

i installed the same cup in my car... you dont need the piece that came with the gauge for installation.. you do need to cut off the studs on the gauge and then once your bulb gets here your going to most likely need to bend the eletrical "prongs" from the bulb to make it fit in the cup... i just bent mine back towards the face to the gauge and it worked just fine. Its a pretty nice little cup and if you dont wanna screw it into anything i just used some double sided tape on and stuck it at an angle i liked inbetween the A-pillar and the dash, hasn't moved a bit.

Post by **Legacy777** » Thu Nov 17, 2005 7:19 pm

I've heard that if you use larger line, response will be better, but you could see oscillations in the gauge, and that restrictor orifice should be used.

Any comments on that?

gt2.5turbo · Post by **gt2.5turbo** » Thu Nov 17, 2005 9:01 pm

i would imagine that the larger the line the less response time cause wouldnt it take more time to build pressure or vaccum with a greater volume of air...

i used the nylon line and then about 2 feet of silicone vacum line and it works just fine

rallysam · Post by **rallysam** » Thu Nov 17, 2005 9:06 pm

Hmmm... it's hard for me to imagine that response time would be much of an issue. The air in the boost gauge line will react very very quickly to changes in intake manifold pressure no matter what diameters we are talking about. It only needs to be faster reacting than the things it is measuring - turbo spooling up or the throttle plate closing - and neither of those are exactly 1ms short events.

For reference. I have basically instant response and I don't see any oscillations. I use probably 4-6 feet of 3mm ID silicone hose leading to a similar length of the hard plastic tubing that comes with the gauge.

BAC5.2 · Post by **BAC5.2** » Thu Nov 17, 2005 9:31 pm

Sam - What did you pay for your Zeitronix setup? I still want Boost and EGT gauges in the car, reguardless of any logging software I may have.

I recently bought a set of Autometer Lunar gauges. Boost/Vac, Air/Fuel, EGT, Trans Temp (I'll use it as a coolant temp gauge).

I'm not so keen on the indiglo look, but it should be OK. I wonder if I could wire them entirely in series and reduce light output. I may have to experiment with this. I might also set them up plug-and-play in parallel.

No idea where I am going to mount 4 gauges though.

rallysam · Post by **rallysam** » Thu Nov 17, 2005 10:18 pm

I paid list. That's $399 because I wanted the in-car LCD display. It's $279 if you don't want the in-car display (still comes with the sensors, logger, laptop hookup, software, etc... just no in-car, real-time display).

There are pics of the LCD here:
http://www.zeitronix.com/Products/zt2/zt2.htm

rallysam · Post by **rallysam** » Fri Nov 18, 2005 7:37 pm

I take back everything nice I said about my boost gauge. I noticed that it read negative 6psi this morning before I started the car! It didn't used to be bad, but now it is way off.

Haven't figured out what's up yet, but it explains why I was getting fuel cut at 7psi as described in the thread below. Looks like I was actually at 13psi.
http://bbs.legacycentral.org/viewtopic.php?t=24008

I would just check your boost gauge against VRG's scan tool now and then to make sure everything agrees.

ultrasonic · Post by **ultrasonic** » Sat Nov 19, 2005 12:15 am

rallysam wrote:I take back everything nice I said about my boost gauge. I noticed that it read negative 6psi this morning before I started the car! It didn't used to be bad, but now it is way off. :mad:

Haven't figured out what's up yet, but it explains why I was getting fuel cut at 7psi as described in the thread below. Looks like I was actually at 13psi.
http://bbs.legacycentral.org/viewtopic.php?t=24008

I would just check your boost gauge against VRG's scan tool now and then to make sure everything agrees.

Hmmm.... 6psi off. That would explain your fuel cut issue! Check for a bend, kink, or other restriction in the vacuum hose between the gauge and the vacuum source.

Post by **Legacy777** » Mon Nov 21, 2005 5:10 am

I played around with the gauge a little yesterday. I'm going to mount it on the steering column to the left. I can see the entire part of the tach, so it should be good.

Other question, is it alright to into the boost bypass (BOV) line? Or should I run the line to the vacuum lines going to the sensors?

vrg3 · Post by **vrg3** » Mon Nov 21, 2005 5:53 am

Consider what would happen should the line you add break... If it's teed into the BOV line you may experience compressor surge. It's a little safer to tee into the line going to the pressure sensor.

Post by **Legacy777** » Mon Nov 21, 2005 3:22 pm

Good point.....didn't really give that much thought.

rallysam · Post by **rallysam** » Mon Nov 21, 2005 4:13 pm

vrg3 wrote:Consider what would happen should the line you add break... If it's teed into the BOV line you may experience compressor surge. It's a little safer to tee into the line going to the pressure sensor.

On the flipside, if the line to the pressure sensor broke (and you are still running off stock boost control) wouldn't you get very high boost? I would imagine that the wastegate solenoid would go 100%. I'm not sure what boost that correspond to. If you have an MBC, then it would just mess up the ECU readings of pressure, which would screw up timing I guess?

You can also tee off the line from the compressor outlet. Same risk, maybe more so. Not much you can do. I've done pretty much all of the above at one time or the other

vrg3 · Post by **vrg3** » Mon Nov 21, 2005 4:18 pm

Nope; you'd get limp mode where the ECU would cut fuel to prevent you from going on boost. Or even if somehow the ECU didn't catch on to the fact that the sensor's hose was disconnected, you'd still be okay because a) the feedback loop in boost control is very slow and b) a sufficiently large correction factor should make the ECU stop controlling boost.

The wastegate solenoid running at 100% duty cycle corresponds to as much boost as the turbo can produce.

An MBC doesn't have anything to do with the ECU's pressure readings. If you look at the vacuum diagram it'll be more clear; boost control plumbing is separate from pressure sensing plumbing.

Teeing off the compressor outlet is indeed more risk, since a leak there will increase the boost level.

Post by **Legacy777** » Thu Nov 24, 2005 1:12 am

Ok, got the bulb kit. However there's three freakin bulbs in there. The kit says to use the one that's in the gauge....well that doesn't help me at all.

Those with the Z-series gauges......what color is the little thing inside the bulb?

http://www.main.experiencetherave.com:8 ... P_6177.JPG
http://www.main.experiencetherave.com:8 ... P_6179.JPG

Post by **Legacy777** » Sat Nov 26, 2005 7:52 am

Got the boost gauge installed today. I'm still trying see how closely it matches the MAP sensor.

I updated pics too
http://www.main.experiencetherave.com:8 ... oostgauge/

ultrasonic · Post by **ultrasonic** » Sun Nov 27, 2005 7:05 pm

Looks good Josh.

When I mounted mine the gleaming silver screws on the mount bothered me, so I replaced them with black socket cap screws from Lowes.

Post by **Legacy777** » Sun Nov 27, 2005 7:51 pm

Yeah I don't really care for the silver screws either, so I'll probably replace them with black ones as well.

Post by **Legacy777** » Wed Dec 07, 2005 4:41 am

The gauge tweaked out on me. It reads -10 in of vacuum when the car's off. I had called summit the other day, and they're sending me another gauge.

rallysam · Post by **rallysam** » Thu Dec 08, 2005 12:36 am

Arg! It got you too, huh?

If I'm not alone, then maybe they would replace mine too even though it's been installed for 6 mo's

Post by **Legacy777** » Thu Dec 08, 2005 4:17 am

autometer has a 1 year warranty.

Who'd you buy it from? Call the vendor up....if they won't honor it.....deal with autometer directly.

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Boost gauges