Things you always wanted to know the answer to [Vol. 4]

[Flibble]

br d said:

Speaking of old wives tales, has anyone ever tried rubbing a bit of meat on your wart and burying it in the garden?

Burying the wart or the meat?

[poing]

Flibble said:

br d said:

Speaking of old wives tales, has anyone ever tried rubbing a bit of meat on your wart and burying it in the garden?

Burying the wart or the meat?

The old wife?

[Blib]

br d said:

Speaking of old wives tales, has anyone ever tried rubbing a bit of meat on your wart and burying it in the garden?

Yep. That was a thing my mother did.

[glenrobbo]

poing said:

Flibble said:

br d said:

Speaking of old wives tales, has anyone ever tried rubbing a bit of meat on your wart and burying it in the garden?

Burying the wart or the meat?

The old wife?

If you bury your meat in the old wife you may well end up with more warts.

[Einion Yrth]

br d said:

Speaking of old wives tales, has anyone ever tried rubbing a bit of meat on your wart and burying it in the garden?

Waste of meat, warts tend to go away in about eighteen months anyway.

[227bhp]

What is the bore and stroke of a recent (1.6 V6 turbo) F1 engine?

[Rich_W]

227bhp said:

What is the bore and stroke of a recent (1.6 V6 turbo) F1 engine?

80mm Bore (Regulated to +/- 0.1mm) see tech reg 5.3.1
52mm Stroke (Merc Hybrid engne)

All the regs are on the FIA site

https://www.fia.com/file/74026/download/23988?toke...

[Lazadude]

227bhp said:

What is the bore and stroke of a recent (1.6 V6 turbo) F1 engine?

Stolen from the technical regs:

5.3 Power unit dimensions :

• 5.3.1 Cylinder bore diameter must be 80mm (+/- 0.1mm).

• 5.3.2 The crankshaft centre line must lie on the car centre plane and 90mm (+/-0.5mm) above the reference plane. The power unit may only transmit torque to the gearbox by means of a single output shaft that must be co-axial with the crankshaft. The output shaft must rotate clockwise when viewed from the front of the car.

• 5.3.3 Valve stem diameter must not be less than 4.95mm.

• 5.3.4 The crankshaft main bearing journal diameter (measured on the crankshaft) must not be less than 43.95 mm.

• 5.3.5 The crankshaft crank pin bearing journal diameter (measured on the crankshaft) must not be less than 37.95mm.

• 5.3.6 No cylinder of the engine may have a geometric compression ratio higher than 18.0.

• 5.3.7 All elements of the power unit specified in the relevant column of the table in Appendix 2 of these regulations must be installed in the union of the volumes that exist between two vertical planes parallel to C-C separated by 700mm and in a box 150mm long, 250mm wide and 800mm high which lies symmetrically about the car centre plane immediately ahead of the front vertical plane.

• 5.3.8 Power unit mountings may only comprise six M12 studs for connection to the survival cell and six M12 studs for connection to the transmission. All studs must be used and may be fitted on the survival cell, power unit or transmission. The installed end of the studs must be M12 and the free end may be a different diameter.

---

[227bhp]

Rich_W said:

227bhp said:

What is the bore and stroke of a recent (1.6 V6 turbo) F1 engine?

80mm Bore (Regulated to +/- 0.1mm) see tech reg 5.3.1
52mm Stroke (Merc Hybrid engne)

All the regs are on the FIA site

https://www.fia.com/file/74026/download/23988?toke...

I did find it after no-one replied, but thanks. I think the stroke is 53. something if they want the maximum capacity of 1.6 litres btw.
You would expect an F1 engine to have an extraordinary piston speed, but when you examine it it's more or less the same as a high performance road car petrol engine. If you have such a thing and are interested post up the bore, stroke and max rpm for a comparison.

[Flibble]

227bhp said:

I did find it after no-one replied, but thanks. I think the stroke is 53. something if they want the maximum capacity of 1.6 litres btw.
You would expect an F1 engine to have an extraordinary piston speed, but when you examine it it's more or less the same as a high performance road car petrol engine. If you have such a thing and are interested post up the bore, stroke and max rpm for a comparison.

Maximum stroke is 53.05mm by my reckoning. Quite short for the piston bore.

I wouldn't expect them to be that fast now they have to hit reliability targets for their engines. Also the RPM limit would tend to limit how fast they can move the piston anyway.

For comparison my car has a bore and stroke of 86mm and a max rpm of 7400.

[227bhp]

Flibble said:

227bhp said:

I did find it after no-one replied, but thanks. I think the stroke is 53. something if they want the maximum capacity of 1.6 litres btw.
You would expect an F1 engine to have an extraordinary piston speed, but when you examine it it's more or less the same as a high performance road car petrol engine. If you have such a thing and are interested post up the bore, stroke and max rpm for a comparison.

Maximum stroke is 53.05mm by my reckoning. Quite short for the piston bore.

I wouldn't expect them to be that fast now they have to hit reliability targets for their engines. Also the RPM limit would tend to limit how fast they can move the piston anyway.

For comparison my car has a bore and stroke of 86mm and a max rpm of 7400.

That's quite a low redline for a square I4 engine like that, mean piston speed at 7400 would be around 21.5 M/S. It's often said 25 MS is the limit for a high performance road engine which you'll find at just over 8500.
To compare that to the F1 engine it will be turning at 14250 rpm to get the piston speed up to 25, at the max rpm of 15000 it's at 26.3.

[Flibble]

227bhp said:

That's quite a low redline for a square I4 engine like that, mean piston speed at 7400 would be around 21.5 M/S. It's often said 25 MS is the limit for a high performance road engine which you'll find at just over 8500.
To compare that to the F1 engine it will be turning at 14250 rpm to get the piston speed up to 25, at the max rpm of 15000 it's at 26.3.

It's not an i4 engine though, which may make a difference. And I think the 7400 is more limited by the valve train than the piston speed.

[227bhp]

Flibble said:

227bhp said:

That's quite a low redline for a square I4 engine like that, mean piston speed at 7400 would be around 21.5 M/S. It's often said 25 MS is the limit for a high performance road engine which you'll find at just over 8500.
To compare that to the F1 engine it will be turning at 14250 rpm to get the piston speed up to 25, at the max rpm of 15000 it's at 26.3.

It's not an i4 engine though, which may make a difference. And I think the 7400 is more limited by the valve train than the piston speed.

It makes no difference to piston speed, what is it though?

[Lazadude]

Guessing Subaru boxer 4, or Jag V8 off the top of my head.

[Flibble]

Lazadude said:

Guessing Subaru boxer 4, or Jag V8 off the top of my head.

The former.

Rev limit is set at the point where the power curve starts dropping. The intake and valve train are the limiting factor above that so even though the engine could rev higher there is no point.

[Roofless Toothless]

popeyewhite said:

Lots of old wives tales about stuff like this over the years, current (unproven) theory is the low pressure that brings bad weather compresses soft tissue which squeezes damaged/repaired nerves. I Googled that as it intrigued me, as I have lots of old joint injuries - but I enjoy cold weather quite a bit with no pain.

You know, I've always wondered about the effect of atmospheric pressure on the way we feel.

I believe there is something like 10% difference in pressure between the centres of depressions and anticyclones. That seems like rather a lot to me. Does our physical or mental health alter under the influence of these extremes?

Popeyewhite is right to point out that weather changes along with pressure, but can we separate this out and just leave the purely barometric effects?

[Lazadude]

I can confirm that injuries (Pelvis and both legs are made from Titanium...) are affected by the weather, cold and rain and some air pressures cause pain/aches.

I had discussed this with a couple of my physios, and apparently its a known thing but at the moment no one can scientifically prove the reason why.

[allegerita]

Einion Yrth said:

Waste of meat, warts tend to go away in about eighteen months anyway.

Trivial info: a wart is called a wrat in Dutch

[Flibble]

Roofless Toothless said:

You know, I've always wondered about the effect of atmospheric pressure on the way we feel.

I believe there is something like 10% difference in pressure between the centres of depressions and anticyclones. That seems like rather a lot to me. Does our physical or mental health alter under the influence of these extremes?

Popeyewhite is right to point out that weather changes along with pressure, but can we separate this out and just leave the purely barometric effects?

I think the answer is maybe. Not aware of any human trials, but this one on rats indicates there might be something there. https://www.ncbi.nlm.nih.gov/pubmed/21130811
They were seeing an effect from just 20 mbar of pressure reduction, which is well below meteorological variation.

Edited by Flibble on Wednesday 19th December 09:03

[RizzoTheRat]

Airliners are typically pressurised to an equivalent of 6000-8000 feet, which gets you down to about 75% of sea level pressure, so people are exposed to lower pressures pretty regularly, I'm surprised there's not been loads of studies on the effects.
Interestingly the International Space Station is pressurised to 1 Atmosphere so maybe NASA think there are some health effects at lower pressures.