Will the standard white poly tubing they sell at home depot hold up to oil and heat if I use it for oil pressure gauge ? I see autometer sells a kit but wondered if its any different ?
Don't know, but why not just get copper if you're going to the hardware anyway? There's a good reason why NHRA won't allow that plastic crap under the hood.
needs something flexible though cause I am mounting it from block to firewall .I am just going to get a stainless steel hose though.
Does NHRA allow copper? I thought it was prone to hairline cracks and they wanted steel lines. Not sure Just asking Posted using the Full Custom H.A.M.B. App!
You could run regular steel line if you put a tension relief coil in it for movement. Google "steel tubing relief coil" for a pic. It's just a couple of loops about 2" in diameter to allow flex between mounting points.
Back in the 60's & 70's I had a couple of cars that I used the under dash aftermarket gauges and they used the clear plastic line. I experienced a catastrophic failure with my 66 Dodge van when the plastic tube cracked and I lost oil pressure on the interstate,,,when I heard the knock it was too late... Haven't used plastic since then. HRP
the tube used is actually nylon which will hold up better . poly has a low melting point and also isn't resistant to oils it will soften and blow out you can find the nylon on line . but IMO your better off to use something metallic . as for NHRA 1:9 general rules . as along as its metallic and smaller than 3/16ths thats all they care about . with the copper you can use the vibration/expansion coils , we used them on High pressure gauges on a boiler pumps without problems for years . and they vibrated real good . you could also use turne coated brake line or copper coated brake line , its steel inside to resist breakage and the coating won't rust .
IMHO, an idiot light with a sender that functions at fairly high pressure is a good idea, especially on engines with ANY sort of external oil line...no matter what you are using, the consequence of failure is very great and so deserves a warning signal. You don't drive watching the gauge full time, and a failure can kill your engine rightdamnnow. NAPA has one that kicks on at 8-12 pounds, more than most, which should give you a moment to hit the switch before a connecting rod shuts down the engine for you.
I agree with Bruce's recommendation about a well placed 'alert' light, but I also would use a flex line, i.e. high pressure hose, between the engine block and firewall, metal tube from firewall to instrument. and Although I am familiar with the relief coil mentioned, I would not rely on the flexibility of metal tubing between engine and body. Actually, my first preference would be an electric guage....as I have experienced an under dash oil line fracture that wet my shoes with engine oil before being noticed. Ray
If the line cracked enough to lose all the oil, the gauge had to be reading 0 oil pressure for a long time. The lines are usually so small that it would take a long time to run all of the oil out if it is cut off completely.
Carquest & O'Reilly sell a kit that is probably nylon. You get the tubing ,nuts & adapters/connectors. I think it is under $20.00
One word NO ask me how I know. It lasted about an hour then blew like a volcano lucky for me it was in the engine compartment and not the passenger compartment.
A warning idiot light AND a gauge is the best way and can be done with a simple "T" fitting allowing you to use both. A gauge and some knowledge can be used to diagnose future oil system problems and maybe distributor problems on the go which you can't do with just a light. I have used the line that comes with the gauges for 48 years and had that one failure only because I cheaped out for a few bucks and used "hardware store" stuff that one time when moving the gauge from one vehicle to another other than that never a problem.
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