loquasagacious
NCAP Mooderator
- Joined
- Aug 3, 2004
- Messages
- 3,636
- Gender
- Undisclosed
- HSC
- 2004
The answer for under/oversteer is the same - bear in mind that this is an out of control situation and in reference to an ordinary driver.
-
Finished your HSC? Check out our University Discussion, Non-School forums or help out next year's HSC students! -
YOU can help the next generation of students in the community! Share your trial papers and notes on our Notes & Resources page
Cars Room Quiz (1 Viewer)
- Thread starter SlipStream
- Start date
transcendent
Active Member
SlipStream said:Dave it's safe to say I've got the trophy.Alrighty, the easy/hard question format seemed to work pretty well before.
EASY - From what country originated the Ford Fiesta?
a) Britain
b) Japan
c) USA
d) Australia
e) Germany
HARD - Which sentence is factually incorrect?
a) Cam lobes are fixed to the camshaft
b) Australian 400m drag record is ~4.7 seconds
c) Henry Ford created the first automobile
d) Turbos are really called Turbosuperchargers
e) F4000 open wheelers use modified Commodore engines
No dishonesty / cheating please!
i don't get how the hard question was hard =_= Henry Ford was the first to mass manufacture automobiles, he didn't invent them.
transcendent
Active Member
oh oh oh i think i know this one but can i nominate someone else to make the questions if i get them right?loquasagacious said:
i remember a magazine once said i may be against your best logic but you should turn into the slide. i think it has something to do with regaining the grip of the tires. so C.
not sure about the number of valve... i think it has something to do with greater power capacity provided to the engine. not sure about the overhead camshaft either but i know that the dual overhead camshaft, DOHC, means that a with a high number of valve provides alot of power, but with great power comes great fuel expenditure and to overcome that the overhead camshaft provides the ability to lock down the number of valves require. wait i know, SOHC, single over head camshaft, means that only a single setting is provided where to improve economy the number of valves used to power the engine is reduced so less fuel used but if you throttle agressively and reach high RPM oil or pressure pushes a rod in place which activates the the other valves providing greater power and dual over head camshafts just means there are two valve settings one, the basic economy one, provides low fuel consumption and low power, the middle one provides medium power and fuel consumption and high one which provides high power and cunsumption. i forgot what VTEC was... i thought it was just something to do with the overhead camshafts and DOHC. hmm.... vehicle... technology, electronic... control? camshaft? isn't it like VVTi? without the i? so V stands for variable time? doesn't that just mean something to do with the pistons running at various rates?
shortygb
BOSer #13412
easy Ill say E.
but i got no idea about the hard one...umm more power/effiency, dohc - power from the engine, vtec is variable valve timing and lift electronic control, it improves the combustion efficency in honda engines.
but i got no idea about the hard one...umm more power/effiency, dohc - power from the engine, vtec is variable valve timing and lift electronic control, it improves the combustion efficency in honda engines.
loquasagacious
NCAP Mooderator
- Joined
- Aug 3, 2004
- Messages
- 3,636
- Gender
- Undisclosed
- HSC
- 2004
Well steven's getting there on the hard one but seems to have confused DOHC with Vtech (i think its the same as vvt-i, mivtec, etc)....
ToO LaZy ^*
n/a
a vtec engine produces power down low and in high rev ranges...something to do with their camshaft timings.....?
you can also rev the shit out of a vtec engine.
you can also rev the shit out of a vtec engine.
Easy: I reckon E - but I really don't have enough experience.
Hard:
DOHC
Ok. Double Overhead Camshaft. So you have two camshafts going in an inline engine, and four going in a V-config (pair on each bank). With the increase of camshafts (as compared to a SOHC), comes an increase of valves.
Instead of 2 (or 3 - like some Maseratis) valves per cylinder, you now have 4 (or 5 - like the Audi) valves per cylinder. Two intake, and two exhaust. As you can imagine the engine being a large air pump, the extra valves facilitate greater amounts of air-fuel mixture entering, and a greater gaseous mixture leaving. So now you have one camshaft operating operating the intake side, and one for the exhaust side. The simple reason for not still using a SOHC configuration is that it is physically impossible to operate 16 valves (on a 4 cyl) with the one shaft (not enough space for all the lobes).
VTEC
This is basically a step up from DOHC, if you will. You have your VVTi, MiVec, VTec, VANOS, and it goes on - each company gives it their own little acronym. But they all stand for the same basic thing - Variable Valve Timing Control. Basically it controls the timing of the valves at various engine RPMs to allow for the best engine efficiency. There are mechanical and electronic systems available. BMW has been using the VANOS technology since '93 just on the intake side - and more recently have applied it to the exhaust as well. I believe it works on the system of having another camshaft in there, with special lobe profiles which come into their own at higher RPMs, say 3000+. These are not activated before hand, due to the engine management. The end result is that the valves (whether intake or exhaust) are staying open, or closed for different (i.e variable) periods of time, to allow for optimum combustion. Clearly at higher RPMs, the pistons are moving at a much faster speed, and to allow for effective combustion, the actual timing of closing and opening valves has to be retarded (or maybe advanced) a little, to allow for a fuller combustion. I am not 100% on how the VTEC system works, but I think each of the camshafts have a whole lot of extra lobes, which are suitable for various RPM bands, and are only pushed into action by the engine management once the engine reaches those RPMs.
That's all I got right now. It has been a LONG time since I last had to explain something like this.
Hard:
DOHC
Ok. Double Overhead Camshaft. So you have two camshafts going in an inline engine, and four going in a V-config (pair on each bank). With the increase of camshafts (as compared to a SOHC), comes an increase of valves.
Instead of 2 (or 3 - like some Maseratis) valves per cylinder, you now have 4 (or 5 - like the Audi) valves per cylinder. Two intake, and two exhaust. As you can imagine the engine being a large air pump, the extra valves facilitate greater amounts of air-fuel mixture entering, and a greater gaseous mixture leaving. So now you have one camshaft operating operating the intake side, and one for the exhaust side. The simple reason for not still using a SOHC configuration is that it is physically impossible to operate 16 valves (on a 4 cyl) with the one shaft (not enough space for all the lobes).
VTEC
This is basically a step up from DOHC, if you will. You have your VVTi, MiVec, VTec, VANOS, and it goes on - each company gives it their own little acronym. But they all stand for the same basic thing - Variable Valve Timing Control. Basically it controls the timing of the valves at various engine RPMs to allow for the best engine efficiency. There are mechanical and electronic systems available. BMW has been using the VANOS technology since '93 just on the intake side - and more recently have applied it to the exhaust as well. I believe it works on the system of having another camshaft in there, with special lobe profiles which come into their own at higher RPMs, say 3000+. These are not activated before hand, due to the engine management. The end result is that the valves (whether intake or exhaust) are staying open, or closed for different (i.e variable) periods of time, to allow for optimum combustion. Clearly at higher RPMs, the pistons are moving at a much faster speed, and to allow for effective combustion, the actual timing of closing and opening valves has to be retarded (or maybe advanced) a little, to allow for a fuller combustion. I am not 100% on how the VTEC system works, but I think each of the camshafts have a whole lot of extra lobes, which are suitable for various RPM bands, and are only pushed into action by the engine management once the engine reaches those RPMs.
That's all I got right now. It has been a LONG time since I last had to explain something like this.
Last edited:
braad
so dead yeah?
- Joined
- Mar 11, 2004
- Messages
- 3,441
- Gender
- Male
- HSC
- 2004
Variable Valve Timing?
like, lazy-econimic shopping trolley, but higher up the revs the other cam comes on strong and creates more power...why Vtec engines are screamers, and why it's hard for some to be turbocharged
thats all i "know" (whether it's right or not is another matter)
like, lazy-econimic shopping trolley, but higher up the revs the other cam comes on strong and creates more power...why Vtec engines are screamers, and why it's hard for some to be turbocharged
thats all i "know" (whether it's right or not is another matter
)
SlipStream
Member
Can we select multiple options for the easy Q? Understeer and oversteer are too fairly different extremes, one being the loss of front traction and one being loss of rear (respectively).
UNDERSTEER: In an AWD car like dad's WRX, you can stomp the A-pedal to cure understeer; in RWD like my mate's Skyline you dial in a dose of the B-pedal to load more weight onto the front for them to bite, OR you can manually fiddle with braking bias by sending more to the rear with the handbrake, OR alternatively you can squish the A-pedal and bring the rear around to meet the front in a bit of oversteer; and FWD like the Charade, well normally you can trail into corners and it bites nicely but lately I've been using the handbrake as well as jabbing the B-pedal with the left foot to load onto the fronts post-turn in. OVERSTEER: AWD and RWD, you can 'just' correct and A-pedal it out; FWD if your car has enough ponies you can power out, but mine doesn't so I just dial in some oppy-lock and let it slide itself back into line. I learnt the hard way not to over-compensate lock...
EASY: So for the understeer I'm going to lock in B, and a little bit of C can help if you've wound on too much lock to begin with. Oh and D and E for oversteer, and I guess if you're carrying too much speed in a FWD and the rear begins to step out then you could even put F to use!
HARD: Oh god, I'm so lazy right now. More valves = better flow of gasses due to greater extraction area = greater efficiency. OHC allows for more valves than OHV because you don't need pushrods, and I guess there's less moving parts which improves reliability and efficiency. V-TECH is Honda's smart VVT, where the cam has two lobes per lifter, or two stages. One has a less agressive lobe for idle to ~5000rpm, where the camshaft is mechanically "pulled forward" so that the next stage (a more agressive lobe) moves onto the lifter that allows for greater valve opening = better efficiency and power at high revs. That's my very summarised attempt.
I think that would have to be the best easy/hard combo we've had in this thread.
UNDERSTEER: In an AWD car like dad's WRX, you can stomp the A-pedal to cure understeer; in RWD like my mate's Skyline you dial in a dose of the B-pedal to load more weight onto the front for them to bite, OR you can manually fiddle with braking bias by sending more to the rear with the handbrake, OR alternatively you can squish the A-pedal and bring the rear around to meet the front in a bit of oversteer; and FWD like the Charade, well normally you can trail into corners and it bites nicely but lately I've been using the handbrake as well as jabbing the B-pedal with the left foot to load onto the fronts post-turn in. OVERSTEER: AWD and RWD, you can 'just' correct and A-pedal it out; FWD if your car has enough ponies you can power out, but mine doesn't so I just dial in some oppy-lock and let it slide itself back into line. I learnt the hard way not to over-compensate lock...
EASY: So for the understeer I'm going to lock in B, and a little bit of C can help if you've wound on too much lock to begin with. Oh and D and E for oversteer, and I guess if you're carrying too much speed in a FWD and the rear begins to step out then you could even put F to use!
HARD: Oh god, I'm so lazy right now. More valves = better flow of gasses due to greater extraction area = greater efficiency. OHC allows for more valves than OHV because you don't need pushrods, and I guess there's less moving parts which improves reliability and efficiency. V-TECH is Honda's smart VVT, where the cam has two lobes per lifter, or two stages. One has a less agressive lobe for idle to ~5000rpm, where the camshaft is mechanically "pulled forward" so that the next stage (a more agressive lobe) moves onto the lifter that allows for greater valve opening = better efficiency and power at high revs. That's my very summarised attempt.
I think that would have to be the best easy/hard combo we've had in this thread.
loquasagacious
NCAP Mooderator
- Joined
- Aug 3, 2004
- Messages
- 3,636
- Gender
- Undisclosed
- HSC
- 2004
I'm going to call Petar right for getting the closest (and getting E for the easy Q).
In terms of the controversy I seem to have ignited with the easy question:
I believe the best option for the relative novice driver in an out of control slide is to counter-steer that is to point the wheels in the direction you want to go and threshold brake. In this way chances of regaining traction are maximised and if/when it is the car will head in an appropriate direction as opposed to sliding in the opposite direction (fishtailing - the likely result of Dylans 'over-locking') or into an obstacle of some sort.
However kudos to Dylan for providing a very comprehensive answer.
The only extra bits I would have liked to see in Petar's hard answer were:
A higher number of valves creates a higher rev ceiling as it is possible to move two smaller valves faster than one larger valve.
DOHC also enables greater tweaking in terms of when the intake and exhaust valves are open.
VVT wise I believe that the timing at high revs is changed so that the intake and exhaust valves are both open concurrently for a greater time period - I am unsure on that though.
In terms of the controversy I seem to have ignited with the easy question:
I believe the best option for the relative novice driver in an out of control slide is to counter-steer that is to point the wheels in the direction you want to go and threshold brake. In this way chances of regaining traction are maximised and if/when it is the car will head in an appropriate direction as opposed to sliding in the opposite direction (fishtailing - the likely result of Dylans 'over-locking') or into an obstacle of some sort.
However kudos to Dylan for providing a very comprehensive answer.
The only extra bits I would have liked to see in Petar's hard answer were:
A higher number of valves creates a higher rev ceiling as it is possible to move two smaller valves faster than one larger valve.
DOHC also enables greater tweaking in terms of when the intake and exhaust valves are open.
VVT wise I believe that the timing at high revs is changed so that the intake and exhaust valves are both open concurrently for a greater time period - I am unsure on that though.
Last edited:
SlipStream
Member
Say, if your FTO was understeering, you'd smoosh the A-pedal and countersteer?
Hello guard-rail / ditch / pole / marsupial.
Take it away petar13!
Hello guard-rail / ditch / pole / marsupial.
Take it away petar13!
loquasagacious
NCAP Mooderator
- Joined
- Aug 3, 2004
- Messages
- 3,636
- Gender
- Undisclosed
- HSC
- 2004
Shit - to many options and I forgot which was which... The answer I was hoping for for the easy one was actually F. My bad. I'll still leave it to Petar13 for getting the hard Q though.
SlipStream
Member
Nah doesn't matter mate, lol. Good to see you're one to admit to your mistakes though; that's a quality many lack. Including myself at times...
Good to see you're one to admit to your mistakes though; that's a quality many lack. Including myself at times...Damn. Thinking of questions is more difficult than I thought. I don't think 'hard' is that difficult though.
Easy -
What is shot-peening? (Let's say conrods)
A) Plating the surface with a tougher more resistant metal
B) Bombarding the surface with shot to pack the metal ions closer together
C) Blasting the metal with glass beads to bring it back to its original surface
D) Bombarding the metal surface with droplets of molten metal to fill in cracks
Hard-
Explain the process of port and polish. Not the wine and sausage.
(Let's say intake manifold)
Easy -
What is shot-peening? (Let's say conrods)
A) Plating the surface with a tougher more resistant metal
B) Bombarding the surface with shot to pack the metal ions closer together
C) Blasting the metal with glass beads to bring it back to its original surface
D) Bombarding the metal surface with droplets of molten metal to fill in cracks
Hard-
Explain the process of port and polish. Not the wine and sausage.
(Let's say intake manifold)
Last edited:
loquasagacious
NCAP Mooderator
- Joined
- Aug 3, 2004
- Messages
- 3,636
- Gender
- Undisclosed
- HSC
- 2004
Don't worry I know how hard coming up with questions is...
Hmmm as far as answers though:
Easy: B
Hard: I have a fair idea but will have to come back to it later
Hmmm as far as answers though:
Easy: B
Hard: I have a fair idea but will have to come back to it later
DaddyK
Is out drifting
- Joined
- Jan 16, 2005
- Messages
- 1,328
- Gender
- Male
- HSC
- 2006
easy B
Hard: I have some idea, not alot. Its where you smoothe out the intake and port and polish them to allow the air to flow easier. Thats all i got.
Hard: I have some idea, not alot. Its where you smoothe out the intake and port and polish them to allow the air to flow easier. Thats all i got.
loquasagacious
NCAP Mooderator
- Joined
- Aug 3, 2004
- Messages
- 3,636
- Gender
- Undisclosed
- HSC
- 2004
Ok porting is enlarging the actual holes feeding air into the combustion chambers and polishing is smoothing the interior surface of the manifold. In the case of the exhaust it is preferable to polish it to a far greater extent than the intake as the slight roughness of the intake actually helps combustion. The exchaust meanwhile is polished to a higher extent to help prevent the build up of carbon (which inhibits airflow).
The comustion champers themselves are usually also polished as part of a complete port and polish job encompassing intake, exhaust and comustion chamber. Ultimately the goal is to increase power by increasing airflow (power being compossed of air+fuel+spark).
The comustion champers themselves are usually also polished as part of a complete port and polish job encompassing intake, exhaust and comustion chamber. Ultimately the goal is to increase power by increasing airflow (power being compossed of air+fuel+spark).
That's right, loquasa... I'll call you Kieran, eh? The one thing I have in mind at the moment - that I would have added was the removing the excess from flash welding (from cheaper manifolds). But it's all good. Well done (Right on both counts).
Go for it.
Go for it.
loquasagacious
NCAP Mooderator
- Joined
- Aug 3, 2004
- Messages
- 3,636
- Gender
- Undisclosed
- HSC
- 2004
Kierans probably easier than loquasagacious
Okies my turn to ask a question again:
Easy: When are you using the maximum traction of your tyres?
A)Normally
B)When the squeel
C)When there's smoke
D)Never
Hard: What are the advantages of having Individual Throttle Bodies (ITBs)?
Okies my turn to ask a question again:
Easy: When are you using the maximum traction of your tyres?
A)Normally
B)When the squeel
C)When there's smoke
D)Never
Hard: What are the advantages of having Individual Throttle Bodies (ITBs)?