General Queries Of New Car & Bike Buyers

[nag2fat]

Question to experts:
How is this conclusion reached that three cylinder engines have a lower power or torque?

IMO three cylinder engines can easily rival their four cylinder counterparts and can even beat them on the run. The only issue is with NVH as they are a bit vibe happy, none else.

BTW what our Baleno owners have to say about the 1.0l in line three cylinder boosterjet engine and the 1.0 Ecoboost?

I agree with TSIVipul. 3 cylinders doesn't means low power and torque. Then what about the 1.0 ecoboost. It is a gem. Manufacturers are now going in 3 cylinder way. Minimal space and maximum utilization. The engine weight is also considerably reduced. Ecoboost got the engine of the year award. Hyundai grand i10 and xcent uses 3 cylinder diesel engines. It has good drivability. And the NVH is also very well controlled. You will be surprised while driving them and a regular guy can't even find out that it is a 3 cylinder. Even the Chevy diesel has 3 cylinders and the drivability is good.

 

[TSIVipul]

Recently I got to drive Polo 1.2 MPI and I was surprised with the fantastic drivability this three cylinder engine is blessed with. It's noisy no doubt but the low end and mid range of this engine are simply unmatched (Polo 1.2 petrol owners, please do pour your experience) and this is a brilliant vehicle for city drives along with highway drives going up to 120 kph.

This is a in line three engine with no gadgetry like VVT etc, just a plain tall stroke engine with MPFi but a very drivable unit.

 

[ameyam]

@TSIVipul,


like you say, we engineers are awesome :-)


Firstly, torque and power are two different things. Torque is twisting force that is applied to turn the wheels. More torque is equal to greater pickup. Torque is usually applicable to move objects from a standstill.


Power is the effort put in to maintain motion. This is usually meant for moving objects


That's why the diesel engines quote lower peak power figures but are great fun to drive around in the cities.


Anyway, if you take a 4 cylinder engine and convert it to a 3 cylinder engine, the torque will be less. So if you take a 1.2L 4 cyl engine (300cc/cyl) and convert it to a 3Cyl engine i.e. 900cc, its going to have a lower torque on account of lower displacement. There is no real replacement to displacement. So, how do manufacturers manage to make usable 3 cylinder engines? Well, its a compromise. For IC engines, the torque and speed are usually inversely proportional. So max torque is produced at low revs and vice versa. However, engineers can play with the bore and stroke length of the piston to modify this characteristics. So if you increase stroke at the expense of bore, the torque will increase but the moving mass now travels more, so engine becomes more vibrational and max rpm gets restricted. But if they increase the bore, moving mass reduces and engine speed increases but torque reduces. So, to produce torquey engines for city driving where top speed is not so much of a concern, usually stroke length is increased making the engine vibe happy. However, there is a limit to how much they can increase the stroke before the torque starts reducing again- lower piston face area is equal to lower pressure bearing area for combustion is equal to lower torque. Engineers work to build a compromise between the two. That's why all these smaller engines are low in torque than the 3 cylinder ones. Another point- in a 3 cylinder engine, the torque is applied to the crank at three points in its rotation- at 0 Deg, 120 Deg and 240 Deg. For a 4 cylinder engine, it is applied at 0, 90, 180 and 270 Deg. SO the average torque is also more in the case of a 4cyl engine
Now, there is a way around this- engines are rated by displacement, not by the amount of working fluid (meaning fuel air mix or charge) the cylinder can accommodate. So, if you compress the charge, you can put in more fuel into a smaller cylinder to produce the same power out of a smaller displacement engine- this is turbocharging or supercharging (depending on which engine and how it is implemented). The catch is, if you turbocharge (i.e. use a turbine on the exhaust gas side to drive a compressor which pumps in the charge into the cylinder), the engine gains power with rpm. So at lower engine rpm and driving speeds, when torque is required rather than speed, the exhaust gas pressure is low and turbo is not turning at sufficient speed turbocharger may not produce enough pressure to produce the required torque where as higher RPMs, the turbo can produce more pressure on the charge. It can also be the other way around. It all depends on the turbo design but usually, turbo design is a compromise between low engine rpm performance and high engine rpm performance. Alternative to this is to go for twin turbos, one for low and one for high engine rpm operation like is done on the TUV's engine. This compromise is also the reason for the turbo lag that most older diesel engines and some modern engines too are known to suffer from.


The trend to use smaller blocks and turbos started in Formula1. In order to control costs, they have come down from 3.6L engines to 3L engines to 2.6L V6 engines to 2.4L V6 engines over the years. Whereas, track speeds are only increasing. It means, if we engineers are presented with a challenge, we just think harder and move forward. The merits of that technology and research put into develop it is now filtering into road cars


Coming back to the Baleno issue, I believe, the turbo Boosterjet engine will definitely be a well tested one because as a concept, this sort of thing is not new. However, expect that engine to behave very differently from the current K12 engine. At the least, that engine will be more noisy and less torquey then the k12


Ameyam

 

[TSIVipul]

like you say, we engineers are awesome :-)

Indeed saarji; being awesome is the habit of engineers

Firstly, torque and power are two different things. Torque is twisting force that is applied to turn the wheels. More torque is equal to greater pickup. Torque is usually applicable to move objects from a standstill.

Power is the effort put in to maintain motion. This is usually meant for moving objects

That's why the diesel engines quote lower peak power figures but are great fun to drive around in the cities.

Saarji I have never been a bright student and hence I have got to learn the power and torque from the signature of one of our forum members whose name I have forgotten (the T.A.I. education system saar); which stated:
Understeer is when you hit the wall from front, Oversteer is when you hit the wall from back
Power is how fast you hit the wall, Torque is how far you push the wall

So simple but so true..

There is no real replacement to displacement.

That's like a man!! Those are the words written by God himself when he built cars.

in a 3 cylinder engine, the torque is applied to the crank at three points in its rotation- at 0 Deg, 120 Deg and 240 Deg. For a 4 cylinder engine, it is applied at 0, 90, 180 and 270 Deg. SO the average torque is also more in the case of a 4cyl engine

Saarji leave the theory and tell me what's the difference when the engine is at it's peak torque point say 3500 rpm. In other words all this angle etc etc blah blah jugaad is happening 3500 times a minute. You tell me what's the difference between the power and torque delivery is at that point and I will give you an eclairs. Note that you should tell me how much different is a three or four cylinder engine is at those engine speeds.

My observation of driving a Celerio and Wagon R 1.1 (Let's keep it simple sirji, everyone around is not an engineer(And no one here has asked for a detailed explanation too) and hence why to confuse the new buyers even more?):

• Celerio: In line 3 cylinder 1.0
• Wagon R(Old Gen, 1.1l): In line 4 cylinder 1.1

The power and torque figures are identical but still Celerio manages to give better FE, have better acceleration and top speed. You explain this to me or prove that the 4 cylinder unit was better and the discussion is over. If you can't then we can stop this "4 are better than 3" discussion here itself and not confuse anyone over the doubts regarding the number of cylinders.

if you compress the charge, you can put in more fuel into a smaller cylinder to produce the same power out of a smaller displacement engine- this is turbocharging or supercharging (depending on which engine and how it is implemented). The catch is, if you turbocharge (i.e. use a turbine on the exhaust gas side to drive a compressor which pumps in the charge into the cylinder), the engine gains power with rpm.

AFR is the key saarji.

The trend to use smaller blocks and turbos started in Formula1. In order to control costs, they have come down from 3.6L engines to 3L engines to 2.6L V6 engines to 2.4L V6 engines over the years. Whereas, track speeds are only increasing. It means, if we engineers are presented with a challenge, we just think harder and move forward. The merits of that technology and research put into develop it is now filtering into road cars

We started from N/A engines and lets talk here about the 4 vs 3 of N/A ones. Turbocharging, supercharging, VVT and what not is there but what about the costs, complications and service costs if anything goes kaput?
Turbocharging doesn't always promise higher fuel efficiency too sirji. I can any day get a higher FE with a 1.5l Honda City than a 1.2l Polo TSi. Civic was always more efficient than Laura TSi.
And yes, what you have to say about the engine life when it comes to these high power density(Power per cubic centimeter) engines against their low powered counterparts?

Coming back to the Baleno issue, I believe, the turbo Boosterjet engine will definitely be a well tested one because as a concept, this sort of thing is not new. However, expect that engine to behave very differently from the current K12 engine. At the least, that engine will be more noisy and less torquey then the k12

I will be surprised if the boosterjet proves to be less torquey than the 1.2K. Having driven the 1.0 Ecoboost, I can bet that this 1.0 Boosterjet will have way way better torque delivery right from idle than the 1.2 ans this is a 3 cylinder engine; not a 4.
Heck, even the 3 cylinder 1.0 also feels more livelier in a Celerio than the 1.2k of the Swift. Don't believe me? Drive it to believe.

Ameyam

Vipul

 

[ameyam]

Vipul.

Hmmm.. too much detail, you are right

Point is, its not just 3cyl vs 4. What i was saying is (and didn't write like an idiot) that you can get the same behaviour from a 3 cyl as a 4 cyl engine by playing with the engine. It does nor mean 4 is better than 3, just that they behave different. To compare apple to apple, i drove the new 3cyl WagonR when i owned and was planning to replace my 4 cyl WagonR and found that the new car didnt have the same grunt but was still nice to drive in petrol mode.

Regarding the boosterjet, i again said it will behave different than the K12. In fact, someone on the Baleno has already seen the boosterjet Baleno testing in his locality & confirmed a noisier engine. Again, that may prove to be a equally competant car, but i already own the K12.

Hope i didnt confuse anyone though. No issues with buying a 3cyl car if you are comfortable with it

Ameyam

 

[TSIVipul]

Ameyam Saarji maybe you are not doing any three vs four but the quoted part feels a but misguiding to me. In fact what feel, it is misguiding. I just couldn't agree on both the points which are in bolds. Rest I am foolish enough to misinterpret frequently and is happy to declare that anywhere.

Yes, 3 cylinder engines are noisy and the torque is less. That does not mean they are unreliable or such, just that you will have a vibrational drive and will need to use accelerator more or you may stall a lot. If you are unsure of the 3-cyl issue, drive a 3cyl car at your driving school and get a feel for it.

 

[autowhiz]

Manufacturing date - is my dealer cheating me?

I am looking forward to purchase a Hyundai Grand i10 Sportz. My dealer is giving me a July 2015 manufactured car, almost a 6 months old car.

Is a 6 month old car acceptable considering the way the Grand i10 is selling like hot cakes? How much old vehicle is acceptable considering I am buying it now in Jan 2016?

 

[Akash1886]

Re: Manufacturing date - is my dealer cheating me?

Is a 6 month old car acceptable considering the way the Grand i10 is selling like hot cakes? How much old vehicle is acceptable considering I am buying it now in Jan 2016?

A fast selling car being kept back at showroom/stockyard points to it being a faulty piece or a unrealized sale. 6 month is too much for a Grand i10. If you are purchasing in 2016 then at max go for November end or December-2015 model.

Regards

Akash

 

[TSIVipul]

Re: Manufacturing date - is my dealer cheating me?

No issues with a 6 month old car given that your dealer is giving you good discounts. Even my Polo is also August manufactured that I bought in December.
Warranty will start from the day of billing and hence no issues. Just go and do a thorough PDI of the car and check for the signs of abuse and odo reading. If everything found okay then go for the car and bluntly ask for at least 50k cash discount along with freebies, free insurance etc. A deal will savings of at least 75k is a must for this car.

OT: Looks like reporter Saab posted when I was writing

 

[ameyam]

Vipul,

That was with reference to a new driver an /or learner. From my own experience, i never ever stalled the corola i was learning on. But when i shifted to a santro at the driving school, i must have stalled it umpteen times. My belief is that new drivers need a torquier engine as the clutch & accelerator balance is not that good. There is nothing more confidence breaking for a learner than stalling in traffic with everyone blaring away on their horns behind. Till they get a perfect clutch judgement, they need to learn to use more accelerator whereas most new drivers just focus on releasing the clutch without stalling. In this context a 4 cyl serves better. Once they have driven around a bit, they will drive the 3 cyl engine without even realising the difference

Ameyam

 

[TSIVipul]

^^Sirji my thoughts are just opposite. I myself learnt on an Armada and hence had a lot of problem with petrol cars in initial days. In fact I never used to get the balance right in petrol cars. It's just then I realised that if I would have learnt on a Matiz or Alto then I would have been a quick learner and would have learnt all the tricks in less than half the time. My friend learnt on his Honda City (I myself taught him) and he learnt right balancing, incline ascending, stop and go on steep inclines and everything within a week after negotiating all types of surfaces.

In my opinion, it is always better to go for underpowered cars for learners instead of likes of Corolla etc (I have burnt my fingers after trying to teach people on Safari and Laura TSi) for two reasons:
1) Lesser the power; more the tricks are learnt. The person becomes better at negotiating inclines, stop go etc.
2) Underpowered vehicle means there are less chances of accidents. More the power worse will be the result of accidental accelerator flooring etc. Believe me, Alto etc can stop if handbrake is pulled but likes of Safari etc give no chance..

 

[ameyam]

Hmm..b may be you are right. Differs from person to person. It took me time to learn the tricks but mostly becasue i had no one to teach me. I bought my Waggie used & used to go out after 11pm to drive it. My area didnt have slopes so getting slopes right was difficult. Till one day i said to hell with it & drove to office and back alone and in peak traffic. More than the traffic, idiotic squeezers irritated me. Then got a driver to sit next to me & tell me the fineries in driving. I never had an accident because my first instinct in panic was to brake. Did have some close calls, mostly with guys who drove in the middle of the night & didnt bother with the "L". Never used the hand brake on slopes other than the first few times & when it got to me needing to get a move on, i always managed to do it. But if i had a alto 800 then, i would have taken more time because i would have kept stalling on slopes and lost confidence

Ameyam

 

[anuraagshenoy]

My dealer is giving me a July 2015 manufactured car, almost a 6 months old car.

Is a 6 month old car acceptable considering the way the Grand i10 is selling like hot cakes? How much old vehicle is acceptable considering I am buying it now in Jan 2016?

IMO, I'll stay away from this deal. With the Grand i10 selling well though not a chart topper gives me a thought of what a 6 month old car is doing at the stockyard? Aren't these guys following FIFO? These dealers leave the cars exposed to the elements and are hardly taken care off.

Check the VIN stamping, DOT code on the tyres and check how the car looks inside-out in thorough detail.

You shouldn't be sad later on with the niggles cropping up.

 

[Auto_Pilot]

Re: Manufacturing date - is my dealer cheating me?

I am interested to know how you came to know that it is 6 month old manufactured car. Does your dealer confirmed it or do you have decoded the VIN?

If the dealer himself confirmed, he must have offered a good deal on the car. If it is other way around, just walk away from the car. If you decide to go ahead with the purchase, do a thorough PDI and also ask for a good discount approx. 1 lakh to compensate.

 

[generalmax]

Re: Manufacturing date - is my dealer cheating me?

A different point here. When I was buying my Celerio,the dealer sold me a May manufactured car in December. It was a kind of cheating as the bank and dealer played spoilsport by transferring my money before they gave the VIN and I do a PDI check. Anyway,I got this Celerio which is crystal clean,not driven as a test drive vehicle.Good tyres (Same month manufacture) .In spite of all my doubts the vehicle was new and t is performing well. The main issue I may come across,is after 2 or 3 years,when the battery may go kaput.
So,In my opinion there is no issue if the vehicle is in stock too.What we think as selling hot may also not be performing well.Vehicle may be in the manufacturers stock yard or with the dealer. Some vehicles go unsold.So ask for a PDI and check for any damage,water seeping in as it is Hyundai (manufactured near Chennai).If it is clear for you,go ahead else do not buy the car.