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reading gauges is easy. it's just like looking at your speedometer or gas gauge but knowing what they mean is the important thing.

different gauges tell you different things. when you start getting into more in depth mods that are drastically changing how your car operates, you need to monitor things so you know everything is in check. you dont have to but spending $300 on gauges that might give you a heads up that something is going wrong is a lot cheaper than spending thousands if you blow your motor. here is what certain gauges tell you.

Exhaust Gas Temperature(EGT) - That gauge has a probe that goes in your header and measures the temperature of the exhaust fumes. This is important when you have a turbo or supercharger because it's a good way to tell if you are running lean(too much air) or rich(too much fuel). Normal temperatures is around 1200-1400*. If you're running significantly hotter, that means your too lean. If your running a lot lower, that means your rich.

Oil Temp and Oil Pressure - Pretty self explanitory. If the pressure gaug fluctuates more than normal, mainly if it drops really low, then something is going wrong or about to go wrong. Losing pressure means the oil is getting out which of course isn't good. As for oil temp, when you start getting a lot of mods on your car, you want to make sure the oil has warmed up before you really start driving hard. In addition, if temps start getting too hot, you might want to back off a little. It's not a big issue but it's a good gauge to have if something ever goes wrong.

Air/Fuel Ratio - there are 2 types. narrowband and wideband. our cars come with a narrowband sensor. the computer uses this sensor(which is in the exhaust) to determine if the car is running lean or rich and then adjusts how much fuel goes into the engine. the ideal ratio on any car is 14.7:1. The comuter tries to maintain that as much as possible. most people have the regular a/f gauge. it doesn't do much other than look pretty because the narrowband sensor just gives you a general reading. lean, stoichometric(which means an even mix, 14.7:1) or rich. then there is the wideband a/f gauge. it's a bit more expensive becuase it comes with a wideband sensor. it replaces the narrowband that your car comes with. it does the same thing but it measures the exhaust fumes more precisely. it will tell you exhaust what your afr is. so instead of lean, stoich, and rich, it will give you an exact number. knowing this number is helpful when you are tuning your car. when you are trying to make a lot of power, you want the mix to be a little rich. the only way to know exactly is with a wideband.

Fuel Pressure Gauge- again, self explanitory. if it drops lower than normal, you have a leak. unless you have made some changes to your fuel pump or the fuel lines, you don't really need this gauge.

Voltmeter - this monitors the electrical output of the car. most people who have audio systems run this gauge. most cars put out about 12-14v of electricity. when the bass hits, the amplifiers draw more power from the altenator, if the power starts falling below 10v, then the car is not getting enough power to run the computer, headlights, etc. i had one of these in my old car and when i was at a stoplight and the bass would hit, i'd have to rev the car a bit to spin the altenator which made more current because i could see my voltmeter dropping around 8v. all the lights got pretty was weird. hahaha.

Boost Gauge - used for supercharged or turbocharged cars. it tells you how many pounds of boot(psi) you're running. it's good to know because if you are tuned for lets say 8lbs of boost and for some reason you spike to 10lbs or even higher, then you need to back off because for some reason, you're making more boost and the computer isn't going to provide enough fuel for that much boost since is tuned for 8lbs.

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