Question about Boost Gauge
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From: Beaver Falls, PA
'cause it's cool. and knowing the engines vacuum can help diagnose some problems. as far as mechanical or electrical, you will get mixed answers. electrical guages are usually easier to install, no plumbing to mess with.
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From: Columbia, MD
Originally Posted by BlackBootyZ71
why do most people have a boost/vac gauge instead of a boost only gauge?
Atmospheric pressure is 14.7PSI. In terms of high performance and racing, boost is anything over 14.7PSI, and vacuum is anything less than 14.7PSI. And since the whole purpose of blowers and turbos is to create boost, we generally use 14.7PSI as a reference point. Therefore, zero PSI on a boost gauge is really 14.7PSI of atmospheric pressure, and -14.7PSI is no air pressure at all. When the blower/turbo is not working, the bost gauge will show close to -14.7PSI, which means the engine is sucking in air on its own. When you drop the hammer, and the boost gauge jumps to anything over 0 PSI, those positive values represent how much air pressure the blower/turbo is forcing into the engine, in addition to atmospheric pressure.
All boost gauges show numeric values from -14.7 up to whatever boost you plan to run. Mine goes to 20PSI.
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On The Tree
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From: MD
Originally Posted by Crunch
Well, I'll try to explain.
Atmospheric pressure is 14.7PSI. In terms of high performance and racing, boost is anything over 14.7PSI, and vacuum is anything less than 14.7PSI. And since the whole purpose of blowers and turbos is to create boost, we generally use 14.7PSI as a reference point. Therefore, zero PSI on a boost gauge is really 14.7PSI of atmospheric pressure, and -14.7PSI is no air pressure at all. When the blower/turbo is not working, the bost gauge will show close to -14.7PSI, which means the engine is sucking in air on its own. When you drop the hammer, and the boost gauge jumps to anything over 0 PSI, those positive values represent how much air pressure the blower/turbo is forcing into the engine, in addition to atmospheric pressure.
All boost gauges show numeric values from -14.7 up to whatever boost you plan to run. Mine goes to 20PSI.
Atmospheric pressure is 14.7PSI. In terms of high performance and racing, boost is anything over 14.7PSI, and vacuum is anything less than 14.7PSI. And since the whole purpose of blowers and turbos is to create boost, we generally use 14.7PSI as a reference point. Therefore, zero PSI on a boost gauge is really 14.7PSI of atmospheric pressure, and -14.7PSI is no air pressure at all. When the blower/turbo is not working, the bost gauge will show close to -14.7PSI, which means the engine is sucking in air on its own. When you drop the hammer, and the boost gauge jumps to anything over 0 PSI, those positive values represent how much air pressure the blower/turbo is forcing into the engine, in addition to atmospheric pressure.
All boost gauges show numeric values from -14.7 up to whatever boost you plan to run. Mine goes to 20PSI.
seems like (as stated above) that this would be a better diagnostic tool.
As for the elec vs. mech. part goes...how do you tie the gauge into your electrical system to monitor boost? (i can understand the mechanical gauge just taps right into a line)
Thanks again for the help.
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From: Columbia, MD
Originally Posted by BlackBootyZ71
so basically on a boost only gauge, you have no idea if you are running less than 14.7psi of boost correct? (because it would just sit at 0, as opposed to showing a negative number?)
seems like (as stated above) that this would be a better diagnostic tool.
As for the elec vs. mech. part goes...how do you tie the gauge into your electrical system to monitor boost? (i can understand the mechanical gauge just taps right into a line)
Thanks again for the help.
seems like (as stated above) that this would be a better diagnostic tool.
As for the elec vs. mech. part goes...how do you tie the gauge into your electrical system to monitor boost? (i can understand the mechanical gauge just taps right into a line)
Thanks again for the help.
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On The Tree
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From: MD
Originally Posted by Crunch
From what I understand, both the digital and analogue boost gauges are hooked up the same way. Its just that the digital version contains a chip that converts air pressure to voltage, and hence the digital display. I assume there is another wire to connect it to the car battery to power it, or perhaps they come with their own lithium batteries.
good deal, so in your opinion...should i just keep the boost gauge they are sending me, or return it for a boost/vac gauge?
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From: Columbia, MD
Originally Posted by BlackBootyZ71
good deal, so in your opinion...should i just keep the boost gauge they are sending me, or return it for a boost/vac gauge?
If someone is selling you a kit with the blower and gauges, it is probably a boost/vacuum gauge. It just may not say that on the box. The Autometer boost gauge does not say anything about vacuum on the box, but it clearly has values below zero.
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On The Tree
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From: MD
Originally Posted by Crunch
They who?
If someone is selling you a kit with the blower and gauges, it is probably a boost/vacuum gauge. It just may not say that on the box. The Autometer boost gauge does not say anything about vacuum on the box, but it clearly has values below zero.
If someone is selling you a kit with the blower and gauges, it is probably a boost/vacuum gauge. It just may not say that on the box. The Autometer boost gauge does not say anything about vacuum on the box, but it clearly has values below zero.
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From: Los Angeles
The e-boost gauge sets up just like the mechanical, but the e gauge taps into an electronic sender that mounts under the hood. The sender has wires that you route into the car and plugs into the boost gauge.
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From: Columbia, MD
Originally Posted by BlackBootyZ71
sorry for the confusion! I ordered the Autometer Cobalt Series Boost Gauge from Thunder Racing...and was wondering if I should send in back in favor of the boost/vac gauge.
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From: MD
Originally Posted by Crunch
It is a boost/vac gauge. I have the same one, but black & yellow, not cobalt.
6160 is a 0-30psi boost only gauge
6159 is the -30:30psi boost/vac gauge
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From: Columbia, MD
Originally Posted by BlackBootyZ71
hmm, they had 2 seperate part #'s
6160 is a 0-30psi boost only gauge
6159 is the -30:30psi boost/vac gauge
6160 is a 0-30psi boost only gauge
6159 is the -30:30psi boost/vac gauge
Did you order that yourself, or is that what came with your kit?
In that case, get the 6159, or else you will have no reading unless you are on full throttle.
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On The Tree
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From: MD
Originally Posted by Crunch
Really?
Did you order that yourself, or is that what came with your kit?
In that case, get the 6159, or else you will have no reading unless you are on full throttle.
Did you order that yourself, or is that what came with your kit?
In that case, get the 6159, or else you will have no reading unless you are on full throttle.
[/QUOTE]Well, I'll try to explain.
Atmospheric pressure is 14.7PSI. In terms of high performance and racing, boost is anything over 14.7PSI, and vacuum is anything less than 14.7PSI. And since the whole purpose of blowers and turbos is to create boost, we generally use 14.7PSI as a reference point. Therefore, zero PSI on a boost gauge is really 14.7PSI of atmospheric pressure, and -14.7PSI is no air pressure at all. When the blower/turbo is not working, the bost gauge will show close to -14.7PSI, which means the engine is sucking in air on its own. When you drop the hammer, and the boost gauge jumps to anything over 0 PSI, those positive values represent how much air pressure the blower/turbo is forcing into the engine, in addition to atmospheric pressure.[QUOTE]
I guess thats where the ricers think there running 20psi and why a rental car would give them a run for there money, lol
Atmospheric pressure is 14.7PSI. In terms of high performance and racing, boost is anything over 14.7PSI, and vacuum is anything less than 14.7PSI. And since the whole purpose of blowers and turbos is to create boost, we generally use 14.7PSI as a reference point. Therefore, zero PSI on a boost gauge is really 14.7PSI of atmospheric pressure, and -14.7PSI is no air pressure at all. When the blower/turbo is not working, the bost gauge will show close to -14.7PSI, which means the engine is sucking in air on its own. When you drop the hammer, and the boost gauge jumps to anything over 0 PSI, those positive values represent how much air pressure the blower/turbo is forcing into the engine, in addition to atmospheric pressure.[QUOTE]
I guess thats where the ricers think there running 20psi and why a rental car would give them a run for there money, lol
Originally Posted by LS1Bird
You'll be glad you did. It's cool to watch the needle bounce around just itching to go to Boost!
Mike M
Mike M
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From: CA
Definately go with the electronic gauge.
Aside from the fact that you have the ability to diagnose problems better because you see vacuum, the electronic gauge also has a warning light and memory, so you can see what your peak boost is and if you overboost.
Aside from the fact that you have the ability to diagnose problems better because you see vacuum, the electronic gauge also has a warning light and memory, so you can see what your peak boost is and if you overboost.
Originally Posted by OOsilverado
Definately go with the electronic gauge.
the electronic gauge also has a warning light and memory, so you can see what your peak boost is and if you overboost.
the electronic gauge also has a warning light and memory, so you can see what your peak boost is and if you overboost.