Tapping for a tapered thread.

[DaveL485]

Certainly won't be 10,000PSI!

Manifold pressure should never spike over 30, unless something goes horribly wrong

As long as it doesn't come out while it's spraying N20 and fuel out at a rate of knots i'll be happy!

[wobert]

AdeTuono said:

Ignore the bks about screwing a taper fitting into a parallel thread. It will fit, but it's not correct, at best, and lethal at worst.

What you have is probably NPT, and more than likely 1/8", but with nothing to compare it with....

You need a tap like this...



notice the taper......

We work in the oil industry, and use NPT all the time. For high pressure applications, DO NOT use in a parallel thread. It won't seal, and will more likely than not blow out. Used properly, an NPT thread is good for 10,000psi.

Note that you can also
screw a BSPT thread into NPT, but there is a slight difference in thread pitch, and you really shouldn't.

#

Not sure about the bks bit..... :-)

I work in the hydraulics industry and we only rate NPT to 500 psi max!

For automotive use, taper into parallel will be fine as it's only holding the nozzle into the manifold.

FYI most engine and transmission oil galleries are sealed using tapered threaded plugs, they are used for mucho cheapness and the fact that you can remove them easily!

HTH

Robert

ex-Lotus, Ricardo, JCB.........

Edited by wobert on Wednesday 2nd March 21:36

[thinfourth2]

Bricol said:

Taper male into taper female doesn't work - you can't turn it properly to screw it in from where it lands when you drop it in.


Here endeth the lesson . . . for now ;-)

Bri

And the lesson is

If you want high pressure fittings don't ask this guy as respectively if you did that with high pressure fittings you could kill someone.

I've spent the past 3 years dealing with 10,000psi and 15,000psi hydraulic control fluid and if you put a BSP parallel into a NPT taper you could kill someone as it will initially seal until the thread fails and you have a bullet. I'e seen the pictures of a 1/2 plug blowing out of a test manifold and going straight through someone.

Not pretty

[AdeTuono]

wobert said:

AdeTuono said:

Ignore the bks about screwing a taper fitting into a parallel thread. It will fit, but it's not correct, at best, and lethal at worst.

What you have is probably NPT, and more than likely 1/8", but with nothing to compare it with....

You need a tap like this...



notice the taper......

We work in the oil industry, and use NPT all the time. For high pressure applications, DO NOT use in a parallel thread. It won't seal, and will more likely than not blow out. Used properly, an NPT thread is good for 10,000psi.

Note that you can also
screw a BSPT thread into NPT, but there is a slight difference in thread pitch, and you really shouldn't.

#

Not sure about the bks bit..... :-)

I work in the hydraulics industry and we only rate NPT to 500 psi max!

For automotive use, taper into parallel will be fine as it's only holding the nozzle into the manifold.

FYI most engine and transmission oil galleries are sealed using tapered threaded plugs, they are used for mucho cheapness and the fact that you can remove them easily!

HTH

Robert

ex-Lotus, Ricardo, JCB.........

Edited by wobert on Wednesday 2nd March 21:36

Well, you're being very conservative in your pressure ratings then.

http://www.precisionhydraulics.net/store/Enerpac-G...

For automotive use, I'd hope you wouldn't mix taper and parallel on the brake system, which typically sees pressures of 1500 psi.

[wobert]

thinfourth2 said:

And the lesson is

If you want high pressure fittings don't ask this guy as respectively if you did that with high pressure fittings you could kill someone.

I've spent the past 3 years dealing with 10,000psi and 15,000psi hydraulic control fluid and if you put a BSP parallel into a NPT taper you could kill someone as it will initially seal until the thread fails and you have a bullet. I'e seen the pictures of a 1/2 plug blowing out of a test manifold and going straight through someone.

Not pretty

Agree, but the OPs situation is not a high pressure fitting, but merely holding the nozzle into the manifold.

We use Konig plugs on our manifolds, and very ocassionally if they are not seated properly, they too turn into bullets when the galleries are pressurised! Not healthy!

[thinfourth2]

wobert said:

I work in the hydraulics industry and we only rate NPT to 500 psi max!

It can do a wee bit more can good old NPT

http://www.hydrasun.com/specification_sheets/EOS03...

Edited by thinfourth2 on Wednesday 2nd March 22:00

[shovelheadrob]

Fogger nozzle, 1/8 npt, use a small amount of ptfe tape and screw in gently, making sure it is in the correct orientation when finished

[DaveL485]

shovelheadrob said:

Fogger nozzle, 1/8 npt, use a small amount of ptfe tape and screw in gently, making sure it is in the correct orientation when finished

Yeah...pointing back up the manifold wouldn't be much cop would it lol.

Plan to seat it as far back up the inlet run as possible, pointing toward the back of the valves.

[thinfourth2]

Do please remove the manifold before drilling and tapping the holes

[shovelheadrob]

I don't know how much you know about nitrous, but a good tool if you are going to get serious is http://www.koehlerinjection.com/nitrous-master-sof... I used to use the program when we raced a nitrous combo with a fair bit of success, it won't make you a tuning wizard, but it takes a lot of the guesswork out. Your biggest danger is detonation so make sure you take timing out.

[DaveL485]

thinfourth2 said:

Do please remove the manifold before drilling and tapping the holes

Its already off....I don't fancy ruining almost £2k worth of Pistons and Liners with swarf!

shovelheadrob said:

I don't know how much you know about nitrous, but a good tool if you are going to get serious is http://www.koehlerinjection.com/nitrous-master-sof... I used to use the program when we raced a nitrous combo with a fair bit of success, it won't make you a tuning wizard, but it takes a lot of the guesswork out. Your biggest danger is detonation so make sure you take timing out.

Not used NoS before. Its a fast road car so not extreme-extreme, the plan is 25bhp per cylinder direct port. I'll be using full standalone and will be backing the timing off when I start trialling the NoS.