boost gauge

[special--k]

So i have been looking at the stock boost gauge. and im wondering how accurate it is?
also, wondering if someone was to change their boost, would the digital cause account for that?

[BoostisLove]

I dont think its accurate at all. I believe its solely based on your throttle position. Anyone to confirm that?

[mazdaspeedjay]

Factory boost gauges on all cars are pretty much crap. The 2010's came out while i was deployed over seas so i haven't gotten to inspect them and see how they are. Except for the one i had on my SRT4 ( Sold my SRT4 for my speed3 and love it by the way LOL ) which even those were know t have problems and brake or eventually read wrong but when they worked they were great cause the damn things were made by autometer. I'd just get a aftermarket one and do a nice clean install. On my '08 i got a electric one from STRi to match the color of the factory gauges and put it in between where the cig. lighter is and the passenger air bag light on the center under the radio. Just the right size and sits flush not poking out or sitting on top the dash or inside the vents. nice and clean.

[Stavesacre21]

Using the dashhawk, I found the stock gauge to be closer then expected. +/- 1 was roughly my findings, so not bad at all. Especially for something integrated into the dash.

I'd understand speculation on it tho...as Mazda couldn't even get the fuel economy computer within 2 MPG of it's real-world counterpart.

[XspeedyD]

Using the dashhawk, I found the stock gauge to be closer then expected. +/- 1 was roughly my findings, so not bad at all. Especially for something integrated into the dash.

I'd understand speculation on it tho...as Mazda couldn't even get the fuel economy computer within 2 MPG of it's real-world counterpart.

umm how are you using a dashawk? from my understanding it doesn't comply with the new ecu

[Stavesacre21]

that be the case, I must be doing something right.

I don't use it normally...it was actually sitting around from my MS6. Just threw it on to see what it would show. It does show a few other things in addition, such as ambient, boost temp, intake, coolant. I stopped checking what it did once I saw what I wanted to see. boost was a lil finicky and intermittant tho, so I wouldn't be buying a $300 unit for that alone. I'd go with a VEI gauge if you're looking for something classy with the red light decor. Looked stock on the MS6.

[XspeedyD]

yeah from what i heard it can only read a few parameters and its glitchy.

[Stavesacre21]

exactly, which is why I wouldn't bank on it.

[TexasSpeedy]

Dashdaq reads all the important stuff except for BAT and KR

[skatethesea]

I would think it to be accurate, but it has so much slop in the read out. And the inability to show boost spikes or over boost. I am biding my time, but will be purchasing a wideband and boost gauge once I figure out where I want to put them.

[ibrewalot]

Silly question, I'm sure, but I've never had a turbo before...why does the boost gauge start at -6? I would have thought it would start at 0.

[NocturnalSpeed]

^ From my understanding it's vacuum... My car sits at -24 or 26 Boost Gauge (http://www.mazdas247.com/forum/showthread.php?t=123775883&page=8#117) when at idle. Depending on what gear im in the vacuum goes higher or lower until you get to a certain rpm and boost kicks in.

I hope thats what you were asking.

[DelB]

i test drove one and it seemed like it got up to 15 psi fast and i didnt really hear or feel it boosting at all. But idk thats just me

[ibrewalot]

^ From my understanding it's vacuum... My car sits at -24 or 26 Boost Gauge (http://www.mazdas247.com/forum/showthread.php?t=123775883&page=8#117) when at idle. Depending on what gear im in the vacuum goes higher or lower until you get to a certain rpm and boost kicks in.

I hope thats what you were asking.

Perfect...thanx for the help.

[skatethesea]

Okay, Vacuum is the correct answer. The most basic answer to this is, the turbo will create a vacuum at a certain turbine speed. This will create a vacuum to pull air out of the engine. (which will actually increase scavenging and better gas milage) As you build "boost" to 0 psi, it is at atmospheric pressure. Basically you are at the nominal 14.? atmospheric pressure for your sea level. After that every thing is bonus horsepower.

Del B. Once you throw and SRI on it you can hear it spooling really well. Though the tiny K04 sounds like a weed eater. lol.

[XspeedyD]

ok i've looked at the stock gauge and my boost gauge and my dashdaq and i have come to the conclusion that the stock gauge is accurate, somewhat. It reads one psi high, when im -1 in vac on my boost gauge and dashdaq im reading 0psi stock. on my car ive always spiked 16 and held 14-14.5, so the stock guage would still have im at full boost when im one psi short. i think they did that on purpose so it looks like ur holding full boost to redline

[Mazdaspeed3Lesa]

Do you have a picture of how it looks? I was going to buy a Greddy one yesterday, but it was 60mm and seemed big! THanks!

[XspeedyD]

picture of what? dashdaq or boost guage?

i forgot to mention part throttle boost and everything is accurate too, just that one psi high.