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Old 3rd June 2005, 18:49   #16
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hey,...think this has been discussed a lot of times before...but at high speeds tire pressure needs to be reduced not increased. also the getz you fel it becoming lighter because of the soft suspension its the "body roll" that you feel common to the accent and honda too.
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Old 3rd June 2005, 19:15   #17
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Post air pressure issues

Quote:
Originally Posted by iceman91
but at high speeds tire pressure needs to be reduced not increased.
iceman:
thats what i was assuming until i read in a couple of car user-manuals that for higher speeds (talking in the range of more than 100miles/hr ~ 160km/hr), the cold-tyre pressure should be increased by +4psi more than the recommended pressure for daily driving.

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Last edited by aah78 : 3rd June 2005 at 19:16. Reason: modifying content
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Old 3rd June 2005, 19:37   #18
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Quote:
Originally Posted by speedsatya
try keepin a gunny bag or two in the boot if driving alone.
Dude, you are funny! LOL. But it is true...the gunny bag causes downforce!!..........but Frank Williams may not like your idea.
What you are sensing is probably high speed lift and it will help by using a front skirt or spoiler.........idea is to prevent air from going under the car and causing lift. If it does, you you smooth it using a flat undertray and push it out thru the back using a diffuser.........F1 tech baby.
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Old 3rd June 2005, 19:49   #19
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Quote:
Originally Posted by Abhay
anupam9055 : are you sure you did 175 in your car ? has it been modded at all?
since it is good for abt 155 (maybe 165 on the speedo)
also all Indicas (Petrol) have a spoiler......as far as I know

but agree that the car is very solid at speeds upto 120/125 (my personal max upto now)
Same question to you, anupam9055? Sure its not modded? Or is that 157?

Yes, the car feels solid at 150 as well but the feeling of overlight steering can be slightly unnerving till you get used to it.

Guys, don't push your cars too much. Journo Veeresh Malik had a blowout in his Indica DLX at 130 kmph recently on the Pune - Lonavala stretch. He was on tubed tyres. Fortunately, there was no damage other than the blown tube but please remember that this could happen to anybody.

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Old 4th June 2005, 10:37   #20
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yep 175 seems a bit much!!!! hope your speedo's ok.
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Old 7th June 2005, 03:18   #21
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Quote:
Originally Posted by Steeroid
I'm not sure how far this is applicable to all cars, but the source is impeccable. One of my ex-colleagues is now part of the BMW Williams F1 team (a pretty junior member) after he finished his specialization in aerodynamics. According to him the spoilers on roadcars are purely decorative as the downforce becomes useable only at speeds > 200 kmph, and that too when the spoiler has been designed after windtunnel tests. SMall changes in the positioning and height makes a huge difference and could even result in the car handling badly (all this at speeds over 200 kmph)......
Do you mean downforce is usable only after 200kmph...

Or that downforce from small spoilers found on most cars is negligible below 200kmph?


Because especially at slow tracks like monaco, downforce settings are very high.

Average speed of a lap at monaco is only 150 or thereabouts.
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Old 7th June 2005, 10:53   #22
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As far as a spoiler goes it is only show and no go and it wont help at all in stabilty since its is put for the aim of making the car looks sporty..
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Old 7th June 2005, 11:20   #23
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Recently I have started pushing my new Baleno to higher speeds. Two weeks back On the Hassan-Bangalore highway I started flooring it and was quite disappointed when the car started feel light (levitation?) at mere 130KMPH, I decided not to push it further.

What could be the reason? I didn't expect that to happen until 160+.
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Old 7th June 2005, 11:56   #24
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Quote:
What could be the reason? I didn't expect that to happen until 160+.
Wierd cos that road is surrounded by trees so, there's no question of high crosswinds. What tyre pressure were you using?

Whats the OE ground clearence on the Baleno?

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Old 7th June 2005, 12:02   #25
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Quote:
Originally Posted by Shan2nu
Wierd cos that road is surrounded by trees so, there's no question of high crosswinds. What tyre pressure were you using?
About 29psi.

Quote:
Originally Posted by Shan2nu
Whats the OE ground clearence on the Baleno?
The OE GC is 170, however I have reduced it to 167.7mm after the tyre change.
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Old 7th June 2005, 12:12   #26
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Usually never one to tell anyone to take his foot off the throttle-
But your car feels light etc, then then thats the best cure initially.

After that look at mods etc.
Samurai, i'm surprised coz i hit an easy 160 in mine . was your road a bit dodgy?? Coz the only place i've had that feeling in on th Mumbai-pune expway, inital stretch bound for pune

Mods- well the wheels and tyres- Upsize (within sanity!!)
Proper spoilers do work. Look at the Ford cosworth WRCs for the mother of all spoilers.
But as we dont have the necessary tech info, its all a bit dodgy
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Old 7th June 2005, 12:18   #27
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Hmmm, 29 psi and 167mm, it should have stuck to the ground. Did the car feel light or did the steering feel light.

Did you get the offset checked before buying your alloys? i still can't see why it should happen at 130kmph, that's cruising speed!!!

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Old 7th June 2005, 12:22   #28
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Quote:
Originally Posted by Mpower
Dude, you are funny! LOL. But it is true...the gunny bag causes downforce!!...........

dude ,
waht are you talking about. i regularly use this on my usual 1000kms drive if there is no one on board.so with 2 gunny bags of sand and cement in my dicky ,the handling was definitely better than what is used to be without it.
i have used this recently even with 2 people on board.it did help on all the turns.

but with 3-4 on board i do not use this as it makes my car overweight .also u wont have space in the boot to carry luggage of 3-4 people.


Quote:
Originally Posted by SAMURAI

The OE GC is 170, however I have reduced it to 167.7mm after the tyre change.
i think ,u shud reduce your tire pressure if your OD has dropped.



and i think its unsafe to reduce the tire pressure for high speed driving.instead its houl dbe 2-3 psi more when continuous high speed driving is to be done
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Old 7th June 2005, 12:51   #29
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satya,

but the gunny bag should be filled right ?? how can you keep empty gunny bags and expect downforce ??

just kidding

Funny - i never felt a thing in the ikon when i was doing abt 150 kmph on the expressway. never felt light or the car never felt like it would lift.

the weight of the car , the GC , the tyres the surface and the wind - these are the factors that lead to the feeling of lightness i guess -

Last edited by normally_crazy : 7th June 2005 at 12:56.
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Old 7th June 2005, 13:08   #30
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Quote:
Originally Posted by normally_crazy
satya,

but the gunny bag should be filled right ?? how can you keep empty gunny bags and expect downforce ??

-

read what i have written

Quote:
Originally Posted by SPEEDSATYA
.so with 2 gunny bags of sand and cement in my dicky
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