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Old 19th September 2007, 16:44   #91
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Where are the mods? Why is there no action when the thread is going way off topic?
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Old 19th September 2007, 16:44   #92
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Quote:
Originally Posted by BlackPearl View Post
drag racers dont intend to spin their wheels during starts but it happens because they have to keep the car in the power band while launching. And you cannot stop a FWD car from spinning wheels when launching in power band unless you put oversize tires. But then oversize tires will have more grip than required and ultimately slow down the car. So drag racers have to live up with some wheel spins to get the best quarter mile timings.
Though im terribly OT,i think vivekiny was referring to burnouts in the water thingy.Not during the launch.Usually done to increase temperature of drag slicks.
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Old 19th September 2007, 16:51   #93
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Sorry guys for the late post. Was enroute to Bangalore for the past 1.5 days. Wow a lot has
happened here. But sadly largely OT.

Quote:
Originally Posted by anupmathur View Post
Nobody chooses a car on that basis. It might happen to have redline at 8000.
Will you please clarify who consists of "nobody"? For starters I am surely not one of those nobodys. I was looking for a OHC VTEC for the last 1.5 months during my stay in my native place but was unable to find one. However, a lot of B15 OHC Non-VTECs were available in the used car market. But I didn't buy it, simple reason being the VTEC revs 300 rpms higher and has more capability of revving higher due to the valvetrain, than the B15 OHC Non-VTEC.
Quote:
Originally Posted by anupmathur View Post

They, hopefully, know what they are doing, and are doing it for a PURPOSE. They KNOW the
consequences, but they fall into what I call a 'priveleged category'! And I say this because
you mentioned 'power-rev', so they were not chasing an rpm, per-se, but 'a meaningful power
package' for a specific application, which might be simply 'an adrenaline rush'!
You must be aware that the only method of increasing the power a NA engine produces is by making it rev higher. Now, a turbo or a SC makes more sense, but then the choice is subjective. So, the RPM is not increased just to increase the feel-good factor. (Wow! my car revs up to 9000!!)

Quote:
Originally Posted by anupmathur View Post
Since we are only talking about non-professional, non-sponsored individuals, I truly envy them: hence I refer to them as the 'priveleged lot'! I envy them; I'm not jealous of them, and I wish I could also afford something akin. (I'm clarifying lest a war breaks out)!
Cheers!
If you are under the impression that the these "non-professional, non-sponsored individuals" are all millioniars, or spending someone else's money, I would say you are dead wrong. It is just about setting one's priorities. I personally know people here in Bangalore who work in BPOs and IT Industry, and take home a modest 25-30K. Out of that, they pay the EMI for the car (~13K) and spend atleast 10-12K each month at their tuner's place. What is left is used for the occasional eating outside. So, as I mentioned earlier but will rephrase it: "World is not only what one has seen in life, a LOT is left to be seen;even though you think you have seen it all".

Quote:
Originally Posted by BlackPearl View Post
so it means that all the rally drivers and drag racers simply waste
power during starting by spinning their wheels??
As vivekiny2k mentioned, the drag racers do it to warm up the slick tires used in professional drag racing. The street-legal tires will not benefit much from these burnouts. Talking about rally, I haven't seen any rally drivers doing burnouts willingly (unless it is to show off or during the occasional powersliding on tarmac stages.

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Originally Posted by WhiteKnight View Post
Whatever that logic may be, you are not contributing anything
worth for the topic of this thread. Please create a new thread to discuss your "logic".
Exactly.

Quote:
Originally Posted by hellspawn View Post
even i have tried the same on the nch vtec,ford ikon 1.6,zen and siena 1.6 and out of all the above cars mentioned,only the ikon and siena seem to wheelspin from 1st to 2nd.
even i havent found the exact reason for this but the only thing common between the ikon and siena is lots of torque low down in the powerband.this could be the reason.
So in your opinion, it depends on the torqueband. Same as what Jaggu proposed. But while shifting from first to second, the last you are doing is being low-down in the powerband. I guess the powerband and torqueband are different across the revband. Or did you mean to say that "the only thing common between the ikon and siena is lots of torque low down in the revband." In this case I very much doubt the fact that a 4-speed carb M800 has more across the revband than a Baleno. (Can be wrong though! The puny M800 hasn't still stopped surprising me)

Quote:
Originally Posted by BlackPearl View Post
drag racers dont intend to spin their wheels during starts but it happens because they have to keep the car in the power band while launching.
Well, minimizing wheelspin during lauch is the aim of any racer (more so for a 1/4 mile). Minimized wheelspin ensures that more power is transferred to the tarmac rather than being wasted during wheelspins.

Quote:
Originally Posted by BlackPearl View Post
And you cannot stop a FWD car from spinning wheels when launching in power band unless you put oversize tires.
Or use launch control. The only disadvantage of a FWD in a drag race is the torque-steer.

Quote:
Originally Posted by BlackPearl View Post
But then oversize tires will have more grip than required and ultimately slow down the car. So drag racers have to live up with some wheel spins to get the best quarter mile timings.
Yup. Without using launch control, reducing wheelspin to nothing (and yet launching the car ensuring that the rev drop is the least) is a very tough proposition. So some wheelspin is unavoidable.

Last edited by doomsday : 19th September 2007 at 16:59.
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Old 19th September 2007, 17:00   #94
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Quote:
Originally Posted by doomsday View Post
So in in opinion, it depends on the torqueband. Same as what Jaggu proposed. But while shifting from first to second, the last you are doing is being low-down in the powerband. I guess the powerband and torqueband are different across the revband. Or did you mean to say that "the only thing common between the ikon and siena is lots of torque low down in the revband." In this case I very much doubt the fact that a 4-speed carb M800 has more torque down in the powerband than a Baleno.
I believe that is not the case in the baleno.Because,even at peak torque my car wont wheelspin.I don't really think my 195's have anything to do with this.See stumpy's car used to wheels spin with 15"ers .. neovas also if im not wrong,so did memos car,and it used to wheelspin at the redline.

Except that,Memo's car had an exedy stage two clutch,stumpy's had an imported valeo clutch from an esteem's parts bin and my car had very new stock baleno clutch.
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Old 19th September 2007, 17:02   #95
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so whether a car wheelspins or not depends on the clutch.
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Old 19th September 2007, 17:04   #96
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Quote:
Originally Posted by akshay1234 View Post
so whether a car wheelspins or not depends on the clutch.
Clutch and torque curve,shifting style,tires,Torque!

But this baleno thing is strange.Haven't had time to drive the car lately .. will check it out later

Last edited by binz : 19th September 2007 at 17:07.
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Old 19th September 2007, 17:14   #97
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Quote:
Originally Posted by binz View Post
I believe that is not the case in the baleno.Because,even at peak torque my car wont wheelspin.I don't really think my 195's have anything to do with this.See stumpy's car used to wheels spin with 15"ers .. neovas also if im not wrong,so did memos car,and it used to wheelspin at the redline.

Except that,Memo's car had an exedy stage two clutch,stumpy's had an imported valeo clutch from an esteem's parts bin and my car had very new stock baleno clutch.
So, the clutch definitely is a factor. As Karan earlier stated:

Quote:
Originally Posted by karan561 View Post
The spring back action of the clutch in baleno would not be as fast as the other cars , depends on how long the clutch is used , and also the distance between the 1st and the 2nd gear throw (how short the shift is)
I don't know anything about how performance clutches differ from stock clutches; but I am guessing they engage and disengage quicker than the stock clutch for the same car.

What we need here is someone who owns a factory stock Baleno, footwear included. (That alone is asking a lot ) and then replicate the same stuff and see if it happens. This brings me to the question: "Are Maruti still offering TDs for the Baleno??? ) They will be as stock as Baleno's can get. I doubt the clutch though, which may be toasted by n number of Ls coming for a TD.

Last edited by doomsday : 19th September 2007 at 17:20.
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Old 19th September 2007, 17:24   #98
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Let me put my two cents to clear things out first here the wheelspin of the wheels is due to loss of traction as well as excess torque.Now what is traction ,Wikipedia defines it on its articles on differentials as
Quote:
. It is therefore convenient to define traction as the amount of torque that can be generated between the tire and the ground before the wheel starts to slip. If the total traction under all the driven wheels exceeds the threshold torque, the vehicle will be driven forward; if not, then one or more wheels will simply spin.
Now this is what is happening in doomsday's case the wheelspin in the ikon and the 800 is probably due to the fact that due the 800 and ikon having shorter 2nd gears it is able to deliver more torque than the baleno and hence these tend to wheelspin,moreover the grip levels in increaing order are 800<Ikon<Baleno( although I may caution here that a worn out tyre has grip than a grooved tyre in dry conditions),the gearing is also made shorter by the diameter of the wheels with the 800 having the smallest diameter wheel with the ikon having a greater diameter than the 800 but much more torque and the baleno(in case it is a vxi with 185 ers) having the greatest diameter among these but it has less torque than a baleno.Another factor that comes into play is how quickly the clutch is released which transaltes into how quick the wheel gets the torque.The last reason which I can see is this when you accelerate hard a twisting force is generted such that your car has a tendency to lift its front up think drag cars whose fronts literally lift up,i am not saying tht you will whelie your car but the ikon with iys greater rear overhang and maybe softer rear suspension is aiding such behaviour and hence causing the wheelspin.what I have said is nothing new I have just given some of my theries alongwith the previous explainations in terms of physics.actually there is something called the physics of racing links below
Stuttgart-West™: The Physics of Racing, Part 3: Basic Calculations, Porsche models 356, 911, 912, 914, 914-6, 924, 944, 928, 993, 986, 968, carrera, cabriolet, speedster, targa, twin turbo including porsche repair, porsche restoration, porsche parts
Stuttgart-West™: The Physics of Racing, Part 3: Basic Calculations, Porsche models 356, 911, 912, 914, 914-6, 924, 944, 928, 993, 986, 968, carrera, cabriolet, speedster, targa, twin turbo including porsche repair, porsche restoration, porsche parts
Amd doom keep on doing R&D you are obviously on the right track quoting the guy who wrote the physics of racing thing
Quote:
``Driving by the seat of your pants'' means sensing the slight changes in cornering, braking, and acceleration forces that signal that one or more tires are about to slide. You can sense these change literally in your seat, but you can also feel changes in steering resistance and in the sounds the tires make. Generally, tires `squeak' when they are nearing the limit, `squeal' at the limit, and `squall' over the limit. I find tire sounds very informative and always listen to them while driving.
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Old 19th September 2007, 17:39   #99
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[quote=vivek_pinkoo;569277]

Quote:
Do you have any meter that I am going too far?
lol. Look closely, I said 'I think'. It is my opinion, I am entitled to an opinion as much as anyone else here is. Please read the post.

Hey Vivek, you can go ahead and reply to this, but I am out of this conversation. Cheers!
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Old 19th September 2007, 17:49   #100
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Quote:
Originally Posted by doomsday View Post

What we need here is someone who owns a factory stock Baleno, footwear included.
guys, don't forget the tire pressure. will make a lot of difference if comparing otherwise similar cars.

EDIT: Doomsday, what is the pressure you maintain in your cars?

Last edited by vivekiny2k : 19th September 2007 at 17:50.
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Old 19th September 2007, 17:52   #101
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Quote:
Originally Posted by revvedup View Post
Let me put my two cents to clear things out first here the wheelspin of the wheels is due to loss of traction as well as excess torque.Now what is traction ,Wikipedia defines it on its articles on differentials as

Now this is what is happening in doomsday's case the wheelspin in the ikon and the 800 is probably due to the fact that due the 800 and ikon having shorter 2nd gears it is able to deliver more torque than the baleno and hence these tend to wheelspin,moreover the grip levels in increaing order are 800<Ikon<Baleno( although I may caution here that a worn out tyre has grip than a grooved tyre in dry conditions),the gearing is also made shorter by the diameter of the wheels with the 800 having the smallest diameter wheel with the ikon having a greater diameter than the 800 but much more torque and the baleno(in case it is a vxi with 185 ers) having the greatest diameter among these but it has less torque than a baleno.Another factor that comes into play is how quickly the clutch is released which transaltes into how quick the wheel gets the torque.The last reason which I can see is this when you accelerate hard a twisting force is generted such that your car has a tendency to lift its front up think drag cars whose fronts literally lift up,i am not saying tht you will whelie your car but the ikon with iys greater rear overhang and maybe softer rear suspension is aiding such behaviour and hence causing the wheelspin.what I have said is nothing new I have just given some of my theries alongwith the previous explainations in terms of physics.actually there is something called the physics of racing links below
Stuttgart-West™: The Physics of Racing, Part 3: Basic Calculations, Porsche models 356, 911, 912, 914, 914-6, 924, 944, 928, 993, 986, 968, carrera, cabriolet, speedster, targa, twin turbo including porsche repair, porsche restoration, porsche parts
Stuttgart-West™: The Physics of Racing, Part 3: Basic Calculations, Porsche models 356, 911, 912, 914, 914-6, 924, 944, 928, 993, 986, 968, carrera, cabriolet, speedster, targa, twin turbo including porsche repair, porsche restoration, porsche parts
Amd doom keep on doing R&D you are obviously on the right track quoting the guy who wrote the physics of racing thing
I was under the impression that the tire grip was in this order: 800>Baleno>Ikon, considering the fact that the 800 has cross-plys, the Baleno (Lxi) is running on 165s and the Ikon is running on the widest set here. Not sure about the size though.

The drag cars wheelie since they are RWDs. (I havn't seen a FWD wheelie yet) The amount of grip and power generated through the rear wheels is enough to lift the front end. Thats the reason they use wheelie-bars (extensions on the rear of the car with a small wheel attached in the end) This effectively extendes the wheelbase of the car (effectively, I repeat) and prevents the front end from lifting.

About the rear overhang theory, does not hold since the M800 does not have any rear overhangs to talk about. And personally I feel that the Ikon is more stiffly sprung than the Baleno (from factory, of course) Can someone please confirm the last fact though?

Quote:
Originally Posted by vivekiny2k View Post
guys, don't forget the tire pressure. will make a lot of difference if comparing otherwise similar cars.

EDIT: Doomsday, what is the pressure you maintain in your cars?
The pressure maintained in the cars is what is specified by the car's owner's manual. Hmmm.. This can be a factor though.

Last edited by doomsday : 19th September 2007 at 17:55. Reason: Read vivekiny2k's post later.
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Old 19th September 2007, 18:11   #102
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This is something to do with engine weight vs body weight?

You can check with fully loaded IKON and see the outcome and I am sure wheel won't spin. And with wider tire also IKON will not spin.
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Old 19th September 2007, 18:26   #103
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Quote:
Originally Posted by vivek_pinkoo View Post
This is something to do with engine weight vs body weight?

You can check with fully loaded IKON and see the outcome and I am sure wheel won't spin. And with wider tire also IKON will not spin.
Can you please elaborate what you mean by the engine weight and the body weight?

Would like to mention though, during all these times; there were the same two people in the car when these shifts were being carrried out. And that holds true for all the three cars. So the passenger weight in every car was constant.

If you are talking about power-to-weight ratio, I'll have to check out the stats. With wider tires though, it is understandable that wheelspin will be reduced, (due to enhanced traction). As I mentioned earlier, we are considering three vehicles in factory stock condition, footwear included.
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Old 19th September 2007, 20:23   #104
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Quote:
Originally Posted by doomsday View Post
I was under the impression that the tire grip was in this order: 800>Baleno>Ikon, considering the fact that the 800 has cross-plys, the Baleno (Lxi) is running on 165s and the Ikon is running on the widest set here. Not sure about the size though.

The drag cars wheelie since they are RWDs. (I havn't seen a FWD wheelie yet) The amount of grip and power generated through the rear wheels is enough to lift the front end. Thats the reason they use wheelie-bars (extensions on the rear of the car with a small wheel attached in the end) This effectively extendes the wheelbase of the car (effectively, I repeat) and prevents the front end from lifting.

About the rear overhang theory, does not hold since the M800 does not have any rear overhangs to talk about. And personally I feel that the Ikon is more stiffly sprung than the Baleno (from factory, of course) Can someone please confirm the last fact .
See without getting deeply into physics what I wnated to say is that as you that you experience a backward force as you accelerate
and a forward force when you brake,now these forces lead to the generation of torque ak.a twisting force such that the torque wants to rotate your car(it is a tendency I am repeating this it does not actually rotate otherwise all your cars would turn turtle as you accerlated) about its tail when accerlating and about the nose when braking.FWD or RWD all experience this torque such that it tranfers all the weight to the rear of the car heavily loading the rear suspension and unloading the front.and yes about the rear overhang theory yes it does not apply to the 800 but then the 800 does not need an overhang it has a light front anyway.And err sorry for the typos in the earlier post.
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Old 19th September 2007, 21:18   #105
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Quote:
Originally Posted by revvedup View Post
FWD or RWD all experience this torque such that it tranfers all the weight to the rear of the car heavily loading the rear suspension and unloading the front.and yes about the rear overhang theory yes it does not apply to the 800 but then the 800 does not need an overhang it has a light front anyway.And err sorry for the typos in the earlier post.
Revvedup, I beg to dis-agree with this!

FWD DOES NOT load the rear at acceleration, it loads the front! Which is why a FWD car can NEVER do a 'wheelie'.
As for loading the front suspension at braking, I think it depends entirely on the brake force distribution, which, in almost all modern cars is heavily biased toward the front wheels with disc brakes. My old HM Landmaster never had any significant nose-dip even in the hardest of braking conditions. Of course we used to be 'thrown' forward, but that was because of momentum being broken and not because of nose-dip.
Please enlighten with the aid of 'physics', if required. Even deep physics is welcome.

Last edited by anupmathur : 19th September 2007 at 21:20.
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