The Technical Questions Thread

[hightower99]

DU rounds are not really hard... 48-49 HR on the rockwell scale.

The high density is what makes them good ammunition.

Basically the heavier the rounds the more KE you can get to the target.

Also self sharpening means that when it hits a hard target it breaks in such a way that it is always sharp... doesn't mean that it shatters completely and sprays sharp shrapnel everywhere.

[drakkie]

Another quick question-

What are steam pipes for in big cities?

Over here we have a lot of petrochemical industry. In the process of creating petrol a lot of heat is left. The steam that normally goes into the air, is now guided through some piping into the city of Rotterdam. Nice and environmentally friendly because the H2O is not released and also relatively cheap.

There is also a regular system of steam pipes in the city. It is heated in a special plant. The steam comes into the houses and is used for heating. It is a little bit cheaper for the people. The other main benefit is that it is much better for the environment.

http://en.wikipedia.org/wiki/District_heating

I hope that answered it.

[NSXType-R]

Thanks, I don't think there are petrol processing plants in NYC, but heating and cooling sounds like a good answer.

[NSXType-R]

Another question-

Is a break in period for a car truly truly necessary?

[baddabang]

Another question-

Is a break in period for a car truly truly necessary?

It helps in extending the life of the motor in the long run. So unless you get a new car every few years, then yes.

I just finished up my break in period and it went by pretty quick. So it isn't a hard thing to do.

[fisetdavid26]

Another question-

Is a break in period for a car truly truly necessary?

Did you think about that after reading my comments in the burning F430 thread and seeing johnny kindly replying I was wrong?

I wonder too now.

[johnnynumfiv]

For instance, do you expect a drag car to drive 500 miles(or whatever amount you want) to break in the motor, no, just run the damn thing.

[NSXType-R]

Did you think about that after reading my comments in the burning F430 thread and seeing johnny kindly replying I was wrong?

I wonder too now.

No, your comment made me wonder about it. I never wondered to think about it.

Thanks for the comments and answering my question.

[Matra et Alpine]

For instance, do you expect a drag car to drive 500 miles(or whatever amount you want) to break in the motor, no, just run the damn thing.

Neither do you expect a drag car to go for 100,000 miles
So a 30 second "run in" is an equivalent !

"Bedding in" is important and some engines need it more than others. For example the Renesis has a coating which is used to bed in the rotor tips and ensure their extended life. Likewise, cams need 10 minutes of "run in" to fully harden the surfaces with the cam follower. Crucial in a race high lift cam, less important in a street car, but if you want maximum life then respecting the materials and engineering involved is important.

The ordinary punter is less likely to follow an engine builders run-in regime and so they adopt a simple-practices approach and so you get "half throttle" for first 200 miles" "max revs of 5000 for 100 miles" or in the case of the Renesis an instruction to occasionally rev to max during "run-in"

[hightower99]

Engines are fully "run-in" from the factory.

The run-in procedure in your car manual has more to do with safety (i.e. if you just bought a new car you don't know how it is going to react so drive slowly in the begining, and to keep you from revving it up in neutral and bounching it off the redline before the engine is warm) then any sort of running-in process neccessary for the engine.

The most impostant thing to remember is to not thrash an engine until it is good and warm. After that you are free to give it a thrashing even if you haven't got more than 5 kms on the odometer.

[Cyco]

Ferrari will tell you otherwise, and last I checked they knew one or two things about engines....

According to them:
"Drive it like you stole it" results in most power, freest revving, most oil use and shortest life.
"Drive like a grandmother" results in a tight engine that never uses oil, but doesn't rev freely and has power flat spots.
As a result they recommend a mix of the two for best life and performance

[Matra et Alpine]

Engines are fully "run-in" from the factory.

SOME engines are "run-in" at the factory.

Please don't confuse readers who may then not follow manufacturers instructions.

Engines YOU know may not have had run-in but many still do, so please don't spread mis-informaiton -- go back and edit it to be correct PLEASE>

The run-in procedure in your car manual has more to do with safety (i.e. if you just bought a new car you don't know how it is going to react so drive slowly in the begining, and to keep you from revving it up in neutral and bounching it off the redline before the engine is warm) then any sort of running-in process neccessary for the engine.

That is also valid but NOT the only reason, see above

The most impostant thing to remember is to not thrash an engine until it is good and warm. After that you are free to give it a thrashing even if you haven't got more than 5 kms on the odometer.

BULLSHIT.
Stop spreading mis-information
Engines aren't going to blow up if your instructions were followed, but serious lifetime issues woudl present themselves !!



Put the petrol can down and step away from the open flame .........

[hightower99]

Ferrari will tell you otherwise, and last I checked they knew one or two things about engines....

According to them:
"Drive it like you stole it" results in most power, freest revving, most oil use and shortest life.
"Drive like a grandmother" results in a tight engine that never uses oil, but doesn't rev freely and has power flat spots.
As a result they recommend a mix of the two for best life and performance

Where can I read about this (I have been looking).

BULLSHIT.
Stop spreading mis-information
Engines aren't going to blow up if your instructions were followed, but serious lifetime issues woudl present themselves !!

Really you think so? I haven't driven a car from new but I did completely overhaul the engine of my bimmer (pratically bringing it back to 0kms engine wise) I have no issues even though I have covered over 40K kms and I thrashed it the moment I got the engine back in and warmed up (less than 12km of driving to warm it up and check everything). IMO it has never felt better. Mind you I do take very good care of it and I never run it hard until warmed properly.

[Matra et Alpine]

Really you think so?

Based on factu, not opinion or single instances.
Your view is based on what ?

I haven't driven a car from new

Ah yes I see the depth of knowledge

but I did completely overhaul the engine of my bimmer (pratically bringing it back to 0kms engine wise)

Overhaul ? New cams, followers, rings, liners, bearings, oil pump, valve stems, valve seats, valves ? If all of those then you've run a risk.

I have no issues

So the fact that someone has lived to 100 and smoked all his/her life is justification for everyoen believing that smoking doesn't harm us ?

IMO it has never felt better.

Compared to what ?
How many cars/engines of varying tune and lifetime have you driven ?



WHOOOOOSH --- the sound of the petrol-soaked ht bursting into flames

[Cyco]

The Ferrari info was posted on the FerrariChat forum