Hard oil supply line fabrication - anyone know how?
 

I am using the BEGI braided lines to bring oil from my passenger side oil supply to the turbo. A couple months ago that lines made contact with my crank trigger wheel and sliced it open. I didn't notice until I got home from work that day and saw the big pool of oil under where my car had sat the night before. I had less than a quart left of oil in my car. I replaced the oil line but I want to move away from that flexible braided line as soon as it's practical.

Does anyone have any experience making their own hard hydraulic (and other) lines? Pictures of completed projects?

Wait did you have the oil feed line running around the front of the motor?

It didn't seem like it would fit around the back... Was I doing it wrong?

Either way, I want to do hard lines next time... I'd love to see hard line goodness.

Hard lines crack. Good quality soft line, good quality ends, keep it away from spinny things.

we have a whole thread on this. I'll try to find it

Why in the world would you run the line around the front?

Because when I built the car I figured that the BEGI oil distribution block was my favorite solution and it routes it around the front unless I did it wrong. I can't see how it can be done any other way with the parts they provide.

I have learned since then and pretty much the only BEGI item I have on my car is the cast manifold. (aside from the distribution block until I can find a better solution)

I have seen hard lines used on aircraft piston engines (almost always used on turbines, but those don't vibrate nearly as much), so it is possible. Rules:

1. Use steel, and only steel. Don't even think of using aluminum.
2. Lines must be secured to the block at frequent intervals. I don't know the interval spacing off the top of my head, there might be something in FAA AC 43-13B.
3. Inspect frequently -- they still crack.

Honestly, soft lines take the cracking worry out. The reason for use in aviation is to save space and weight.

The Easy button on a post-1995 Miata is a well-secured soft line run around the back of the block. 1995 and prior year blocks have an oil feed port on the exhaust side.

What size does the line have to be? -3AN, -4AN?

I'm pretty sure you can just get a 1/8" bspp tee with a NPT port (that's how I'm running my oil pressure gauges) with the appropriate NPT->AN fitting.

Or get fancy and drill/npt tap the fat banjo bolt up top

Thank you. My "spare block" is from a mazdaspeed so it has the oil feed on the drivers side but it doesn't have the oil pump to drive VVT (unless I am mistaken) so I am throwing rods into my current motor this winter just to get on the road faster. When I have time and money I will build the mazdaspeed motor (with VVT head) and that will solve many of my problems.

Is it safe to Tee off of the VVT supply line at the back of the block?

Yes, that is where all 01-05 Miata's that have VVT Tee from.

Right, but will pulling turbo oil supply out of that location cause any significant problems? I know the oil supply for turbos is VERY small but I would rather k
know than assume.

Oh, if you're gathering from the stock oil pressure sender location, then you need 1/8 bspt not bspp. Bspp is on the banjo bolt to the block.

Your turbo is internally restricted or do you have to use a pill in-line? You can tee from this area without issue, I did this on my bp4W as well.

I'm currently only teeing this location on my vvt motor for pressure sensors as I'm using a 94 block and sourcing oil from the driver side.

If you use a sandwich plate, move the pressure sensor to the plate, and then tee from the old sensor location as this will be filtered oil. Don't feed a turbo from a sandwich plate.

Agreed. Also, you see hard lines on diesel engines a lot too. It is certainly possible for a hard line to work and last, just has to be designed correctly.

I ran lots of hard lines, with a bit of soft line to absorb shock. Had to buy the 37.5° flare tool. I got the rigid one. It works frigging awesome. Check my build.

Stainless OK? Or is work hardening due to vibration an issue?

Most of the hard lines I see on aircraft engines are stainless. But I don't know the alloy. Keep in mind that "stainless" encompasses a wide variety of alloys with all kinds of properties. Research carefully.

All of mine are stainless. I forget the alloy, I got it from McMaster-Carr. I belive that they only have one that they recommend for flaring. Seamless. ..

Found it- 304 seamless, .035

I had a stainless single flare feed line on my race car and my turbo dd for a long time they work great. I just recently switched to a braided line. I bought the line from mcmaster and I used swadgelok fittings I got from work instead of buying a flare tool. The fittings are expensive but no fancy tools needed and they are very very strong and never leaked.