72GoldOlds350

Hi Everyone!

I'm about to get 3-4 (hopefully 3 for ease of installation) aftermarket gauges, but I will only need to get 3 (which I'm hoping is the case), as long as the factory oil pressure gauge works well enough.

Car is a 1972 Cutlass. Basically, I'm hoping the factory oil pressure gauge is accurate enough so I don't have to get an aftermarket gauge for that, as well.

Thank you!

Koda

It doesn't have numbers, so accuracy is not really possible anyway. You need "some" oil pressure when the engine is running. Typically, people run Oil Pressure and Coolant Temp in aftermarket gauges because that leads to catastrophic failures. Volts is not as critical, you will drain your battery, and fuel means the engine will shut off, but, again, with fuel, you need "some." An oil gauge or light is the first gauge I would have in a car, then speedometer, then fuel, then temp, then a tach, then volts, then I guess a clock.

oldcutlass

What are the 3 or 4 gauges your thinking about?

72GoldOlds350

I am for sure getting Trans Temp, Fuel Pressure, and Coolant Temp. Oil Pressure for the 4th if I need to.

Fun71

Agreed.

Fuel pressure is something you check when you're troubleshooting an issue; otherwise check it once to confirm it's correct then go on with your life.

I think trans temp would only matter on a tow vehicle; on a daily driver Cutlass there's no benefit to continuously monitoring that. Install an external trans cooler if you worry about high temps, then you can rest at ease knowing you have more than adequate trans fluid cooling capability.

Oil pressure, coolant temp, and voltage would be things to monitor continuously.

72GoldOlds350

Thanks for the tips.

For some background, Mark R just built me a SBO 350 that just laid down 530hp/580tq on the dyno. I'm also getting built a TH400 with high stall, and an entirely new fuel tank and system (electric).

I'm for sure getting trans temp, and coolant temp. So I guess Oil pressure supersedes fuel pressure.

Schurkey

"I" would screw the engine temperature gauge sending unit into the trans pan and drive it for a couple weeks. If there's no temperature issues with the trans, pull the sending unit, plug the hole in the trans pan, and put the sending unit into the engine. You've proven that in typical use, the trans doesn't get too hot--so stop obsessing. OR you've proven that the trans DOES get too hot, so you install a cooler and re-test. If the trans no longer gets too hot...put the sending unit in the engine, and stop obsessing.

"Too many gauges" looks spiffy on a show-car, but just leads to driver fatigue in real life.

Fuel pressure is a pain in the ***. Either the gauge is under-the-hood and therefore useless in normal driving, or you buy an expensive isolator, or you buy an electric gauge. Why would fuel pressure change except you have a system failure--and that's going to be fairly obvious even without a gauge. Race car...sure. Street car...probably not.

Engine temp, oil pressure, volts is standard 3-gauge aftermarket arrangement. You already have an oil gauge on the dash--verify it with a "shop" oil pressure tester by teeing the shop tester into the same port as the OEM sensor. Easy enough to read a certain oil pressure on the shop gauge, and compare to needle position on the dash gauge. Once you've seen some hot-idle pressure and compared to the dash gauge, and some cold, fast-idle oil pressure and compared to the dash gauge..."I" would likely use the dash gauge and stop obsessing. I could be persuaded to add an aftermarket oil pressure gauge if the dash gauge was proven to deliver wacky indications and replacing the sending unit didn't fix the problem.

Now we're down to maybe two gauges--engine temp and volts. Yup, I'd want both of them (unless the vehicle already had those gauges in the dash.)

Ammeters "can" be a dangerous fire-starter (depending on how they're designed 'n' wired.) Father-in-law damn near smoked his '72 Skylark because of a crappy ammeter that had the entire alternator output running through the ammeter under the dash. Better gauges don't route all the vehicle power into the passenger compartment. For my purposes, a volt meter is just plain easier and does essentially the same job--tells me if the alternator is keeping up.

I have an engine oil temperature gauge on the boat. Boat sees extended, high-rpm use. The old engine would touch 300 degrees oil temp if the RPM went high enough. The new engine doesn't have that problem--but the gauge remains. (Mild obsession--I'm just too lazy to remove it) If you had an engine block that was filled with grout, I'd also consider an oil temp gauge.

oldcutlass

Are you doing new in dash gauge packs or going under dash? The three gauge under dash cluster I always install are engine temp, oil pressure, and volts. There are four gauge clusters to add a trans temp. They make fuel pressure gauges that screw into the fuel line under the hood. I like the mechanical type gauges.

70cutty

IMO oil pressure is more important than trans temp. I have "standard 3" and I added fuel pressure as a 4th gauge. Running a electric fuel pump, I like to know how it performs.

72GoldOlds350

Thanks, that is the exact same pod I'll be using. I'm getting Trans Temp because I'll also have a gear vendors overdrive unit and a high stall.

Electric full-sweep fuel pressure gauge for the new fuel system.

Coolant temp.

(I already have a digital voltmeter where the cig lighter used to be for my stereo amps)

I'll add a 4th for oil pressure.