I've been thinking about the guages I'd like to get and wondering if there is anything that could be a detractor from going with mechanical pressure guages. I'm looking at oil pressure and fuel pressure guages along with cooling temp guages. My dad seems to have it in his head that a mechanical OP guage is not a good idea since if you somehow rupture the line you will lose engine oil. I agree that losing oil is bad, but what is the likelyhood of rupturing a line? Also, I'm not sure if a mechanical or electric fuel pressure gauge is the way to go. Could yall elaborate on the pressure guage setups yall have, and why - from your experience- you should or should not get a certain guage. I want to be as safe as possible - but don't want to spend a small fortune on electric guages (and snake wires all over the place) if there really isn't a need to. Thanks for any insight yall will provide.

 

I prefer electrical - no isolators to worry about. All mechanical fluid pressure/temp gauges should be used with isolators to keep hot fluids out of passenger area. Especially fuel.

 

Hard to beat elec for simplicity and ease of installation. Some would argue that mech is more accurate, but 2% - 3% difference in accuracy is not a big deal to me.

 

I was TOLD.. that mech guages where.. what was said earlier.. Always meant to be shielded. Not to be simply installed into a drivers driving compartment. And most of them are which sometimes mounted OUTSIDE of the car, like you see some guages on peoples hood.

Or something like that.

I'd go with electrical. Less risk of hot oil scalding and spilling over your *********.
Or even worse, hot flammable fuel pouring over your nut sack and in your eyes, and catchign on fire and burning, and melting your skin off. Probably won't die, probably just live through it with my testes melted off.

.... Up to you! I run electrical Defi link guages in my car.

 

I'm not sure how much of the inaccuracy is old wives tales. There's a lot of racing "knowledge" that's been handed down for far too long and is no longer accurate. If anyone has any knowledge on the accuracy of current electrical gauges vs. mechanical, I'd love to hear it.

 

Not racing gages, but still gages.. If I have a choice of trusting a pressure transducer or a mechanical pressure gage, I chose the mechanical gage. If you get two or three mechanical gages (in cal.) together and put them in a system, they'll agree with each other.. if you get two or three pressure transducers (in cal.), they'll all say something slightly (within a percent or two, usually) different, and they'll wander about for no obvious reason. The wandering is the part the ticks me off in my job.

I still use electrical for most stuff because it's hella convenient compared to mechanical, and the wandering is not _really_ enough to cause a significant difference in the data I need to gather..

Besides, mechanical's cool because I like a good gage that I can tap on..

Summary:
If I have both, I trust mechanical more. If I can only put in one, and I need to view the data remotely, electrical is the way I go.

 

I'm thinking of mixing the guages up I guess. Fuel Pressure will be mechanical and in the engine bay. Oil pressure probably will be electric with a warning light set for 20 or so PSI. Not sure on Water Temp, but I guess electric will work ok.

MechE00, I hear you about the pressure transducers wandering, I know how force transducers need to be zeroed for each use... that's what makes baseline reading so neccesary for testing with them.

 

I am in the process of installing an electric water temp gauge, and a mechanical oil pressure gauge. I went all out and bought aeroquip lines and fittings to hook up the oil pressure, instead of the flimsy nylon tube that is supplied with the autometer gauge. I will be installing them in a bezel replacement on the dash.
What I really like about mechanical gauges in the 270deg sweep as opposed to the 90deg sweep the electrical gauges have.
I have also been told (and I agree) that a mechanical water temp gauge will have its measuring equipment pretty far from the block, and therefore will lose accuracy.

I have also seen fuel isolators for sale in every racing equipment catalog I receive - that will make is easy for you to get the necessary equipment to safely hook up your fuel pressure gauge, if you decide that you want it in the cockpit.

hth.