[JayD]

Originally Posted by Samurai

What? You get best engine braking in diesels. I bought diesel Jeep over petrol Jeep/Gypsy because of engine braking.

Gypsys have superior normal brakes!!

Offroading nuts love diesel engines because of engine braking.

What about torque, economy etc??

[Thad E Ginathom]

Originally Posted by petrohead

How exactly does engine breaking work ? Im sorry im a newbie and google dint turn up good!

With a very large and heavy hammer.



Try googling Engine braking!

(and don't mind me: I make the same mistake. Often.)

[vikram_d]

Good one Thad

20 chars strike.


Note from the Team-BHP Support : Please do NOT use any methods to bypass the 20 character limit. Thanks!

[mclaren1885]

Originally Posted by Steeroid

McLaren, who the hell is your supplier? Your posts are getting crazier by the day.

Steer, come on own up. Let us share some of this with the others as well.

[Mpower]

Originally Posted by mclaren1885

Tires: Tires play as important a role as brakes do. Remember the only form of contact between the car and the road is tires. Respect that, if you want to be safe & quick. Softer compounds give you tremendous grip while at the same time they have less life. If you are one of those who drives fast, do not compromise on tire compound to longetivity of tires. In trying to make sure tires long laster, you might end up shortening your own life. A complete NO NO!

So what are you saying here. I need a softer compound if I need to drive fast?

You are missing some basic points.

• Make sure your tires are not blad or close to bald
• Check the air pressure in your tire to ensure they are not over or underinflated.
• Check the speed rating of your tires
• Do not mix old and new tires

[ananthkamath]

What is the point of this thread? If it is to educate enthusiasts on how to drive fast SAFELY, then some of your comments in the latter half are moot and may even be misleading to the intended audience.

My comments, addressed to the intended audience, not mclaren in particular: (1000th post BTW, cheers

Originally Posted by mclaren1885

2. Know the limitations of your car: Not every car is meant for high speed driving.

I disagree. I would rephrase that to "Not every driver is meant for high speed driving". Every car has an envelope of performance that can be objectively measured, and a competent driver is consistently able to exploit the boundaries of that envelope much better than a less competent driver. Point is, if YOU think you can drive better than the next guy, get yourself to a trackday and see how fast you can do a lap. Then get someone who is known to be an expert driver to drive your car and see the difference for yourself.

Originally Posted by mclaren1885

- Ability to accelerate quickly: As silly as this sounds, it is very important. Often I have noticed that people take unwanted risks to test the top speeds of their cars just to see what it can do. Remember, the longer it takes, the more risk one is taking with traffic around. I know some who just wont give up and take unnecessary risks till their goal is reached. If you have a car that accelerates quicky, you will reach your goal quicker, and probably will ease up a bit once that goal is achieved.

sure, but that isnt the reason its safer. its safer because of the ability to get yourself away from sticky situations.

Case in point: The shift pattern on almost all modern motorcycles has the neutral in between 1st and 2nd gears. Reason is, you are always in gear in a sticky situation where you need the highest possible acceleration from the vehicle.

Originally Posted by mclaren1885

- Suspension: Suspension plays as important a role as brakes while driving fast. If one is just driving fast in a straight line, suspension plays minimum role.

Wrong. Ever ridden in a car with shot rear shocks? It is all over the place specially on a bumpy surface, even on an arrow straight road. Suspension is equally important in all situations because it is what keeps the tire in contact with the road, contrary to popular belief.

Originally Posted by mclaren1885

But trying taking a corner at high speeds, you will know how important it is to have a good suspension setup. To be able to take a corner quickly, what a good suspension should do is to keep body roll to its minimum and keep the rear end from stepping out. If your suspension setup is not upto the mark, you can get your springs stiffened or go for height, damping adjustable suspension kits.

This is too much of a generalization. The goal in suspension design is to keep as much of the outside tire in contact with the road as possible, and to ensure as smooth of a weight transfer as possible to the outside tire. But I digress. With all else equal, a more competent driver will always be faster on a given road with stock suspension than a less competent driver with modified suspension, whatever the extent of those mods may be, unless the stock suspension is horrendously bad.

Originally Posted by mclaren1885

Tires: Tires play as important a role as brakes do. Remember the only form of contact between the car and the road is tires. Respect that, if you want to be safe & quick. Softer compounds give you tremendous grip while at the same time they have less life. If you are one of those who drives fast, do not compromise on tire compound to longetivity of tires. In trying to make sure tires long laster, you might end up shortening your own life. A complete NO NO!

I agree with Mpower, there are far more basic things that an average enthusiast can do to improve his driving skill than dicking around with tire compound. Simply put, first use the checklist given by Mpower, then think about upgrading to a different tire.

Originally Posted by mclaren1885

Vehicle dynamics: Remember how weight trasfer takes place on a car. When you accelerate, the front end lifts, pushing all the weight to the rear. Similarly when you brake, all the weight comes to the front. When driving fast, if you approach a corner too fast, remember never to brake hard into a corner. Because what happens is, the weight transfers to the front, the rear end of the car being very light will tend to step out and hence you lose control of the car. Best remedy is to, brake early and start accelerating through a corner.

Its called trailbraking. Believe it or not, this is how the fastest drivers get those times, specially on a stock or close-to-stock car which is set up to understeer at the limit. But you're right, for anything less than expert driving ability, its not the way to go.

Originally Posted by mclaren1885

Engine Braking: Remember, the quickest way to stop is to use a combination of engine braking along with the B pedal. It ensures you are always in control of the vehicle. Contrary to what most people think, engine braking is one factor that could improve your braking distances by miles. Don't bother about what damage it could do for your engine, bother about your life. Engine braking is something that will not come to everyone through instinct. It needs practise.

I don't remember a single panic braking situation in my 9-odd years of driving where I had the time to downshift, specially in a car with an H-pattern gearbox. In a motorcycle, maybe, yeah, with a lot of practise. But otherwise this is purely academic.

[kuttapan]

Originally Posted by ananthkamath

I don't remember a single panic braking situation in my 9-odd years of driving where I had the time to downshift, specially in a car with an H-pattern gearbox. In a motorcycle, maybe, yeah, with a lot of practise. But otherwise this is purely academic.

Ah, a person who finally understands what a panic situation is. It is exactly that, a PANIC situation. And no matter how experienced you are, you panic because you did not see it coming(say a child running across the road suddenly where he/she was not even in your field of view to begin with), reaction times are nil here, for 99.99% of the people, survival instincts take over and you do what comes to you. I doubt how many people can do a downshift in a panic situation. If you have time to downwhift, it probably wasn't a panic situation to begin with.

EDIT :- I am talking about speeds this side of 80, not the insane highway speeds like 200+. In those situations, yes you get time to downshift, if you managed to detect a panic situation.

[iceman91]

kuttapan at 200+ also you wont get time as you are going way to fast. Unless you have the distance. Imagine at 200+ how quickly you can cover 50mtrs.

Ananth agree with you on most.

[Samurai]

Originally Posted by Steeroid

Samurai - diesel engines ignite on compression. You compress regardless of whether you have a foot on your accelerator, except probably in modern ECU-based diesels which your CJ surely isnt.

Ah, I don't have much experience with CRDi, I was thinking older diesels.

Originally Posted by JayD

Gypsys have superior normal brakes!!
What about torque, economy etc??

Brakes will get heated and become useless if continously used while coming down in ghats or offroading.

Originally Posted by ananthkamath

I don't remember a single panic braking situation in my 9-odd years of driving where I had the time to downshift, specially in a car with an H-pattern gearbox. In a motorcycle, maybe, yeah, with a lot of practise. But otherwise this is purely academic.

Totally agree, one has to be superhuman to shift gears during panic braking, one might overrevv and screw the engine. I would just use brakes and steering.

[mclaren1885]

Originally Posted by Mpower

So what are you saying here. I need a softer compound if I need to drive fast?

You are missing some basic points.

• Make sure your tires are not blad or close to bald
• Check the air pressure in your tire to ensure they are not over or underinflated.
• Check the speed rating of your tires
• Do not mix old and new tires

I agree to the above points. But just to point out a few examples, a swift d that comes shod with JK Vectra's are useless at speeds of 160 kmph. We all know that the Vectra's are hard compound, now a friend replaced them with PP2's (which are a lot softer in compound) and the grip has increased ten folds. I mean, the grip you get from a average tire is certainly nowhere close to a good performance tire.

Originally Posted by ananthkamath

I would rephrase that to "Not every driver is meant for high speed driving". Every car has an envelope of performance that can be objectively measured, and a competent driver is consistently able to exploit the boundaries of that envelope much better than a less competent driver. Point is, if YOU think you can drive better than the next guy, get yourself to a trackday and see how fast you can do a lap. Then get someone who is known to be an expert driver to drive your car and see the difference for yourself.

Completely agree with your point. When I meant not all cars can be driven fast, I meant you cannot have a qualis and hope to do speeds like a esteem. Yes, you are right that if a person X can drive around a track in xx seconds another person Y can drive the same car in +/- xx seconds. So its how well you adjust to the car.

sure, but that isnt the reason its safer. its safer because of the ability to get yourself away from sticky situations.

Point added.

Wrong. Ever ridden in a car with shot rear shocks? It is all over the place specially on a bumpy surface, even on an arrow straight road. Suspension is equally important in all situations because it is what keeps the tire in contact with the road, contrary to popular belief.

Ananth, I am not talking about "busted suspension" situations. A stock setup working well isn't under the same kind of stress in a straight line as it is under a corner. For eg, compare the suspension between the Sonata Embara (super soft) to an Elantra (quite stiff). Whereas you can take the Elantra into a corner at a greater speed, trying to do so with the Embara will give you a scare. I was referring to stiffer suspension only to be able to hold greater speeds into corners for those who intend to drive fast.

With all else equal, a more competent driver will always be faster on a given road with stock suspension than a less competent driver with modified suspension, whatever the extent of those mods may be, unless the stock suspension is horrendously bad.

Completely agree. Take the accent crdi and the OHC Vtec for example. Wonderful cars, good engines but suspension is such a big let down. One could kill themselves easily trying to extract the best from their engines.

I agree with Mpower, there are far more basic things that an average enthusiast can do to improve his driving skill than dicking around with tire compound. Simply put, first use the checklist given by Mpower, then think about upgrading to a different tire.

Agree again. But I have had two experiences. Once when my Baleno was shod with Eagle F1's and the comparison to the grip levels after switching to AD07's. AD07's being ten folds better, actually 100 folds would be more apt. Secondly, switching S-drives on an elantra to PP2's. Phenominal difference in braking and corner speeds.

Point I am trying to make is many people (including me) think it is least necessary to upgrade from stock tires to better ones for better grip and to increase efficiency in braking. But its only once you have moved onto a different set (upsize, compound change) of tires that you realize how wrong you were earlier.

Its called trailbraking. Believe it or not, this is how the fastest drivers get those times, specially on a stock or close-to-stock car which is set up to understeer at the limit. But you're right, for anything less than expert driving ability, its not the way to go.

Can an average Joe be able to handle a tail that has stepped out and get out safely? You know how sharp reflexes, being able to throttle than brake to shift weight to the rear, feeding opposite lock etc have to be done in such situations. I think its better to brake before entering a corner until that time you understand the nuiances of getting a slide into control.

I don't remember a single panic braking situation in my 9-odd years of driving where I had the time to downshift, specially in a car with an H-pattern gearbox. In a motorcycle, maybe, yeah, with a lot of practise. But otherwise this is purely academic.

Hhhhmm. Maybe I have just been fortunate enough to be able to ride with some people who haven't ended up just sitting on the brakes in panic situations and locked their tires. v1p3r, memo45, tadu to name a few.

Also, I know instinctively when you see a biker cross a road when you are doing say 140kmph the first thing you do is either swerve or just sit on the brakes. That is because it comes instinctively to us. But with a little practise don't you think you can frame your mind to brake, downshift and then use the power to steer away safely. Another thing with just sitting on the brakes is that you are often not under any control if the tail steps out under braking.

[Sahil]

One piece of advice for people driving fast especially in Bombay...watch out for potholes !

They can totally ruin the party for you, so its best to floor it on a road thats frequented by you as most often potholes develop in this city overnight.

[Sideways]

Originally Posted by ananthkamath

What is the point of this thread?

Exactly.

Originally Posted by ananthkamath

some of your comments in the latter half are moot and may even be misleading to the intended audience.

I agree.

I also agree with Ananth's explanation with suspension setup. Ask a novice to drive a car with a race suspension and I guarentee he will spin in the first corner.

As Ananth has already mentioned, if you need to drive fast or know how good you are, do it in a controlled environment. Theres no use taking unnecessary risks on a public road.

Just cause you (no one in particular, I am generalising) have (or think that you have) Carbon fibre or titanium scrotum, and think you can do anything (which generally would be considered highly stupid by normal people) only means that you are a maniac and nothing else. Skill is a different thing altogether.

No offence meant to anyone in particular.

[vnabhi]

Originally Posted by mclaren1885

Also, I know instictively when you see a biker cross a road when you are doing say 140kmph the first thing you do is either swerve or just sit on the brakes. That is because it comes instinctively to us. But with a little practise don't you think you can frame your mind to brake, downshift and then use the power to steer away safely. Another thing with just sitting on the brakes is that you are often not under any control if the tail steps out under braking.

If I were in such a situation, then my entire attention would be on avoiding a collision. This means I'd be hitting the brake hard and have both hands on the steering wheel to steer clear of the biker. I cannot afford to take a hand off to change the gear. Such a luxury is possible only if the biker is some distance away.

[nma83]

Saw this term in manveet's post: 4 or 5 panel Wink mirror
Can anyone enlighten as to what this is?

NMA

[me_sid]

HI guys, first and foremost Rahul & Mavneet, its an interesting and informative article. In the threads I read about engine breaking being overrated. Ahem I beg to differ, though I am a kid out here in TBHP am a wise old man of 32 driving for the last 20 odd years or so. In my experience engine breaking is absolutely essential, in highways and downhill. tapping on brakes all the time causes it to get heated and jammed, then what? A small experience that happened a couple of months back with a fellow Tbhp'ian. He was taking a test ride in a second hand Opel Optra, the car was handling great in the city, then it was decided to be ripped, in Kolkata theres this AJC bose road flyover which is a good place for ripping during sunday afternoons. He took the car at 110 Kmph and a yellow cab swevers in front he taps the break nothing happens, the car doesnt slow down even a bit while its evident he is almost standing on the brakes. Whats the option now? engine breaking, he did it and all the 4 escaped unhurt. Engine breaking is essential. Secondly ask any 4x4 junkie when they are doing downhill, steep gradient, the rule is no brakes no clutch no accelerator, who then controls the decent, engine braking.

Anyways now coming to softer compound tyres and their needs. The basic reason if I logicaly think, is control rather than speed. The entire weight of the car rest squarely on those 2-3 odd sq cms's of tyres that are in contact with the surface, now in higher speed that area of contact also reduces. If the compound is softer then I think the softer material would be able to provide better traction than the normal hard material for the given area of contact. So controllability becomes better, so does your confidence, hence maybe a little step on the gas