Go Back   Team-BHP > BHP India > Team-BHP Reviews > Long-Term Ownership Reviews


Reply
 
Thread Tools Search this Thread
Old 29th June 2008, 08:29   #241
BHPian
 
sameel's Avatar
 
Join Date: Jan 2007
Location: cochin
Posts: 268
Thanked: 3 Times
Default

any ideas on how much the brake pads last!!.
mine was replaced yesterday! . the car has now done close to 21k kms!!
luckily the front pads were only worn out the rear are ok.
cost for replacing front brake pads is 2k rs. same for rear pad set also.
they say the petrol verna brake pads last much more!! i am happy only i am using the verna how it ought to be used.
and yes about all this turbo issue ..my verna still pulls like crazy in all the gears the first cog is deadly, always bang my head onto the head rest when i shift to second cog ..hehe. second and third cog are awesome take it to 110kmph in third gear most time..fourth cog pulls like from 70-150kmph like crazy, but i am even more crazier and at times shift at 110kmph to fourth. and bang!! she just goes crazy!! fifth gear pulls from 90kmph all the way to the top. twice i have taken it to 220kmph in the L&T bypass that is only possible when you shift to 5th cog at 150-160kmph!!. i never kind of use the 5th cog , too dangerous for my kind of shifting in kerala. 150kmph itself is crazy in kerala. and yes fastest way to reach that speed is in 4th gear. so fifth is only when dad is in my car. lol. but yes i and dad have driven the car in 5th gear between 70-80kmph , i always loose it and go to 120-140 once in a while, still i got ~20kmpl. while dad is very disciplined. he once got ~23kmpl..whoa. for my kind of driving i get 16-18kmpl in highway and 16kmpl in cbe city. the bike(luna..lol) fellows are a pain!! so i am very decent. but yes for proper tuning i have been told that the first 10k-15k must be run in all Rpm range..dad did the disciplined driving and the occasional all rpm driving was due to me.
so end result i have a well tuned Verna. even after all my blasting, when i drive decently i get way more than what other verna owners get!!.
even for us here in Bosch, our testing procedure involves relaxed driving with occasional ripping this allows the new engine to get well tuned to all styles of driving.
the only ripping style is dangerous so is the only relaxed driving.
the trick is simple , run-in hard, while still being relaxed.
peace out.
sameel.
sameel is offline   Reply With Quote
Old 29th June 2008, 17:07   #242
Senior - BHPian
 
hellstar's Avatar
 
Join Date: Dec 2006
Location: Bangalore
Posts: 1,071
Thanked: 17 Times
Default

Quote:
Originally Posted by sameel View Post
any ideas on how much the brake pads last!!.
mine was replaced yesterday! . the car has now done close to 21k kms!!
luckily the front pads were only worn out the rear are ok.
cost for replacing front brake pads is 2k rs. same for rear pad set also.
they say the petrol verna brake pads last much more!! i am happy only i am using the verna how it ought to be used.
and yes about all this turbo issue ..my verna still pulls like crazy in all the gears the first cog is deadly, always bang my head onto the head rest when i shift to second cog ..hehe. second and third cog are awesome take it to 110kmph in third gear most time..fourth cog pulls like from 70-150kmph like crazy, but i am even more crazier and at times shift at 110kmph to fourth. and bang!! she just goes crazy!! fifth gear pulls from 90kmph all the way to the top. twice i have taken it to 220kmph in the L&T bypass that is only possible when you shift to 5th cog at 150-160kmph!!. i never kind of use the 5th cog , too dangerous for my kind of shifting in kerala. 150kmph itself is crazy in kerala. and yes fastest way to reach that speed is in 4th gear. so fifth is only when dad is in my car. lol. but yes i and dad have driven the car in 5th gear between 70-80kmph , i always loose it and go to 120-140 once in a while, still i got ~20kmpl. while dad is very disciplined. he once got ~23kmpl..whoa. for my kind of driving i get 16-18kmpl in highway and 16kmpl in cbe city. the bike(luna..lol) fellows are a pain!! so i am very decent. but yes for proper tuning i have been told that the first 10k-15k must be run in all Rpm range..dad did the disciplined driving and the occasional all rpm driving was due to me.
so end result i have a well tuned Verna. even after all my blasting, when i drive decently i get way more than what other verna owners get!!.
even for us here in Bosch, our testing procedure involves relaxed driving with occasional ripping this allows the new engine to get well tuned to all styles of driving.
the only ripping style is dangerous so is the only relaxed driving.
the trick is simple , run-in hard, while still being relaxed.
peace out.
sameel.

Sameel,

thats nicely put across and yes the importance of the run in period cannot be understated.

Bro - my bake pads are still going strong at over 41,000 KMS , but again i think brake pad life is a function of your driving style , i for one had managed to take the car to 200KMPH on the L&T bypass and then had to ease back on the pedal as the going was getting very scary and there were very bad cross winds. I as far as possible avoid rapid deccelaration ( i cant say that about the accelaration part though) .
hellstar is offline   Reply With Quote
Old 29th June 2008, 18:01   #243
Senior - BHPian
 
Shan2nu's Avatar
 
Join Date: Feb 2004
Location: Hubli - Karnata
Posts: 5,525
Thanked: 87 Times
Default

Quote:
@Shan2u -The Verna CRDI is a great car and has excellent straight line performance and is very drivable in the city with appreciable roll on times as well. I agree with your opinion on handling as well. The talk is not about turbo lag after 2000, but the reluctance of boost(when turbo starts reving optimally) to set in particularly in the 2nd gear. This boost is kind of the USP of the Verna CRDI. This is not something that everyone has faced. Hellstar has no problems after 40K kms. I faced at around 9K.
Turbo boost is rpm dependant and not gear dependant. So it's not possible that you get a diff boost pressure in 2nd gear when compared to the other gears.

Shan2nu
Shan2nu is offline   Reply With Quote
Old 29th June 2008, 18:15   #244
Senior - BHPian
 
ported_head's Avatar
 
Join Date: Mar 2004
Location: Mumbai, India
Posts: 2,391
Thanked: 8 Times
Default

Quote:
Originally Posted by Shan2nu View Post
Turbo boost is rpm dependant and not gear dependant. So it's not possible that you get a diff boost pressure in 2nd gear when compared to the other gears.

Shan2nu
Boost control is wastegate dependent. By using an electronic boost controller, it is possible to limit boost wrt gear. As long as interfaced with an EMS that supports it. Hondata has this option. So do quite a few others. So it's no trouble for an OEM unit.
ported_head is offline   Reply With Quote
Old 29th June 2008, 19:52   #245
Senior - BHPian
 
Shan2nu's Avatar
 
Join Date: Feb 2004
Location: Hubli - Karnata
Posts: 5,525
Thanked: 87 Times
Default

Quote:
Boost control is wastegate dependent. By using an electronic boost controller, it is possible to limit boost wrt gear. As long as interfaced with an EMS that supports it. Hondata has this option. So do quite a few others. So it's no trouble for an OEM unit.
But does the Verna have this? There has to be some sensor telling it what gear is engaged coz the gear changes are not controlled electronically.

Shan2nu
Shan2nu is offline   Reply With Quote
Old 29th June 2008, 21:07   #246
BHPian
 
sameel's Avatar
 
Join Date: Jan 2007
Location: cochin
Posts: 268
Thanked: 3 Times
Default

hehe..
hmmm ok.
there is something known as GSHdem in the ECU world !!
it stands for Gear Shift Harmonization Demand!!.. ehh what happens in depending on engine rpm and vehicle speed and torque demand , a parameter known as. TraNumGear varies from 0-7 that is for neutral to gear 7 , and -1 for reverse.
this is just the basic ok, and guys please done try to understand this(its too dam technical!!) i have done system testing (integration testing in this thing , SO YES I KNOW THIS STUFF!!) , the ecu decides the optimum gear in automatic transmision, electronically controlled type.
but in manual gear its a switch principle, its like a 6-way switch .
where each corresponds to a specific gear , this is for a 5-forward, one reverse gear pattern,.
so in effect when we put the gear, TraNumGear changes form 0-5 and -1 for reverse.
now there is something known as HLSDEm , DiaDem, and EISGov also,
these things stand for High - Low Speed Demand, and Engine Idle Speed Governer,
i hope you guys are aware , while we switch gears, the gear shifts must be harmonized as in the injections to the engine cylinders should not go crazy..hehe .. for that the ECU needs to make certain adjustments and that is done by the module GSHDem.
so by now you guys do will be knowing. TraNumGear value is used by ECU to sense which gear the Car is in now!!.
and then depending on the torque demand from the ETS module - Engine Torque Structure. the boost is decided. so yes technically the boost does vary in gears , that is like , lower gears need most boost for greater torque, but again it depends on engine Rpm in first place because for the turbo to spool up especially in FGT min 1900rpm is needed to get proper boost till then the car will be dead!! so the thumb rule is the lower gears will be given most boost still this physical limitation is present , but this is made up by increasing injection quantity by the ECU.
understanding the whole thing is impossible unless you are a nerd like me..lolz.

so simply speaking in Automatic transmission ECU decides TraNumGear depending on drive mod and torque demand.
but in manual gear , we choose the value of TraNumGear ..ok clear i hope.
and depending on the value , the boost does vary and yes on different gears different boost happens but this is more flexible in VGT but kind of narrow in FGT ,
actually each time we shift gear, the ECU goes mad ..haha because very few of us shift gears at properly as in with accordance with the driving conditions guys like me make the ECU go mad all the time.. .
and @ hellstar.. man you are a really nice driver your brake pads are ok at 41k!!! whoa. keep it up dude.
and hey you have petes tuning box installed right? man i wish i could tell you the deal, but what to do i have a personel commitment to you know who..hehe .

and i can kind of see this misconception that mileage is depended on Engine Rpm...as in if we kind of go in low gears and drive in low rpms , the efficiency will be there????
that is very wrong , it is partially right but the truth is in first and second and third, the ECU injects more Fuel for lower rpms also, so the best way to get mileage is always ride in higher gears because the ECU injects lower quantity of fuel!!.
the parameter is InjCharActVal its like a 5bit message , in which each bit corresponds to a specific injection(pilot main post)..and i have seen that for higher values of TraNumGear, the InjCharActVal becomes a 5 bit message with only bit 2nd set( i.e main injection ..cant do without..hehe) and mostly one more bit is sit pilot or post ..just for emission norm meet and stuff and yes in indian cars,..Post is absent..we indians are so mileage consious!! even OEM guys have abanded Post injections..haha .
but in first , second and third gear..i.e lower values of TraNumGear , most bits of InjCharActVal is set, i.e more fuel is injected[pilot and post are active..meaning more fuel is spent!!] , so guys ride in higher gear as much as possible , and RIDING IN LOWER GEAR IN LOW RPM WONT SAVE YOU FUEL!! .

hope this thing clears some doubts..and hey please dont try to grasp this whole stuff it will only confuse you guys. lol.

peace out
sameel
sameel is offline   Reply With Quote
Old 29th June 2008, 22:50   #247
Senior - BHPian
 
kpzen's Avatar
 
Join Date: Oct 2004
Location: Faridabad
Posts: 5,545
Thanked: 1,598 Times
Default

Sameel. Interesting post. Thanks for sharing.
kpzen is offline   Reply With Quote
Old 29th June 2008, 23:19   #248
BHPian
 
Join Date: Jun 2008
Location: Bangalore
Posts: 32
Thanked: 0 Times
Default

@sameel-Great info thanks!

@hellstar-thanks mate

@rippergeo-This was noticed after returning from a trip to Kerala(approx 600 KM ws covered oneway)

Any way there seems to slight improvement after the work done on it. Keeping my fingers crossed.
lediablo is offline   Reply With Quote
Old 30th June 2008, 01:03   #249
Senior - BHPian
 
Shan2nu's Avatar
 
Join Date: Feb 2004
Location: Hubli - Karnata
Posts: 5,525
Thanked: 87 Times
Default

Quote:
but in manual gear its a switch principle, its like a 6-way switch .
where each corresponds to a specific gear , this is for a 5-forward, one reverse gear pattern,.
so in effect when we put the gear, TraNumGear changes form 0-5 and -1 for reverse.
now there is something known as HLSDEm , DiaDem, and EISGov also,
these things stand for High - Low Speed Demand, and Engine Idle Speed Governer,
i hope you guys are aware , while we switch gears, the gear shifts must be harmonized as in the injections to the engine cylinders should not go crazy..hehe .. for that the ECU needs to make certain adjustments and that is done by the module GSHDem.
so by now you guys do will be knowing. TraNumGear value is used by ECU to sense which gear the Car is in now!!.
and then depending on the torque demand from the ETS module - Engine Torque Structure. the boost is decided. so yes technically the boost does vary in gears , that is like , lower gears need most boost for greater torque, but again it depends on engine Rpm in first place because for the turbo to spool up especially in FGT min 1900rpm is needed to get proper boost till then the car will be dead!! so the thumb rule is the lower gears will be given most boost still this physical limitation is present , but this is made up by increasing injection quantity by the ECU.
understanding the whole thing is impossible unless you are a nerd like me..lolz.
But do cars like the Verna, OHC, SX4 etc have this sort of technology (especially in India)?

Moreover, why would lower gears need more boost for greater torque? The gear ratios themselves multiply the torque. The OHC produces close to 1730nm at the wheels at 4700rpm in 1st, while this figure goes down to 414nm at the same rpm in 5th. So technically, if i want to overtake a vehicle in 5th, i would want the ECU to give me more torque from the engine.

And the only thing preventing the injection from going crazy when i shift is the lack of throttle. If i shift with my right foot flat on the throttle, i don't think the ECU is capable of controlling fuel injection, atleast until it hits it's cut off at 7100rpm.

What you're talking about may be present on some high end cars, but i doubt the sub 10 lakh segment have such technology (where the ECU has control over what gear is engaged on a manual transmission car).

Shan2nu
Shan2nu is offline   Reply With Quote
Old 30th June 2008, 01:33   #250
BHPian
 
sameel's Avatar
 
Join Date: Jan 2007
Location: cochin
Posts: 268
Thanked: 3 Times
Default

thats just the outside dude.
the cars which you mentioned , i have no idea about the petrols but the verna has got this coz its EDC16 gen ecu. petrol engines rev away to glory in no time .. the gear ratios are enough to do the torque delivery ..in diesel cars its required to always get in maximum air possible!! the mixture always runs as 'lean' first gear the ECU injects more fuel, more air is needed so more turbo boost. and yes the rest is as usual the gear ratios take care..but yes the ratio is kept very short.. in verna thats the case.
and read my post carefully. the ECU doesnt need to calculate which gear the vehicle is in now..because the switch output tells the ECU which gear the vehicle is in. the switch input is us shifting gear , so even in the very top end cars also, in manual tranmission the stick shift to be precise, the ecu has no control over which gear to be used. we are the master of choosing the gear, so to make the injections proper, the ECU does GSH after GSHDem module gives out the changes to be made(ECU does this chnges) and as far as petrol cars are concerned they are more complex because stochiometric ratio must always be maintained. and i dont think just the lack of throttle is the only problem!! , what about the air intake, there is the throtle valve to take care of the amount of air getting in(in non-turbo cars in turbo cars, boost should also be taken into account. )..this is again dependent on how much fuel is injected , which again depends on demand from ETS . so yes all cars with MX7, MX9 , MX17 ecu , do have this ..so honda city should be having a ECU probably its the MX7 series, not sure its the old one right.
so the point is ECU will never have the control on which gear is to be chosen in a manual transmission its impossible..lolz.
and yes the petrol cars...keeping the foot flat on the acclerator while shifting, though they call it as quick shift or simultaneous shift or something, as a CRS engineer i would call it as thrashing your engine and gearbox, the clutch will be fried!!!
i can go into very deep technicaly but most guys on this forum would become confused rather than understand something..lolz.

peace out
sameel
sameel is offline   Reply With Quote
Old 30th June 2008, 02:18   #251
Senior - BHPian
 
Shan2nu's Avatar
 
Join Date: Feb 2004
Location: Hubli - Karnata
Posts: 5,525
Thanked: 87 Times
Default

No, what i wanna know is, how does the ECU know what gear is engaged on a M/T. How does this system work. How does the engine differenciate betwenn 2000 rpm in 1st, 2nd, 3rd etc.... You mentioned about a "switch output", is there some sort of wire/cable connecting the transmission to the ECU?

Shan2nu
Shan2nu is offline   Reply With Quote
Old 30th June 2008, 08:15   #252
Awaiting Email Confirmation
 
Join Date: Sep 2007
Location: India
Posts: 1,745
Thanked: 19 Times
Default

@sameel- that answers a doubt I had as to why the car smokes at high rpms only in 5th gear(3500rpm-4000rpm) and not in the lower 4 gears(Pete'd swift)
didnt make sense at all to me till I read your post above. Used to think that fuelling was rpm dependent only and not gear dependent.

but, could you also tell us how the ECU knows which gear we're in?(shantanu's question). is there a sensor? and where is it placed usually?

also- about fuel efficiency,
when in higher gears at lower rpms, i.e below the engines rev range where max torque is available, wont we lose FE?
eg- in a verna in 4th gear, at 40kmph, the rpm is less than 1500, but the car is still pulling nicely. are we wasting fuel doing this? Shouldnt we change to 3rd for FE?

@sameel- thanks, great post.
rippergeo is offline   Reply With Quote
Old 30th June 2008, 09:35   #253
BHPian
 
sameel's Avatar
 
Join Date: Jan 2007
Location: cochin
Posts: 268
Thanked: 3 Times
Talking

@rippergo
dude in fourth gear at 40kmph, its absolutely fine[ the duration of injections at high gear in low rpms will be small). when we switch over to 3rd, another set of injections might or might not happen, it can be either the same injection pattern as in 4th or maybe different[ still duration of injections will be more!] . but usually the third gear will be multyplying the toque much more than the fourth gear so, its better to be in 4th gear[ less enery conversion loss compared to 3rd gear] and the verna has got 4th , 5th gear as overdrive that is they wont loose effeciecny even if the car slows down to a speed less than recomended for the specific gear just like in 5th also the car can go in 55+kmph, and for 4th 40kmph is also fine .

the next question.
well there is two ways of realisation for which gear is selected .
one is v\n ratio vehicle speed to engine speed ratio.
and the other is a message from CAN interface from GCU gearbox control unit basically that is an ECU for the gearbox, here the GCU has a sensor which gets the gear as a switch output. and yes in simple terms the GCU is connected to ECU by wire. ok. so technically there should be a connection to ECU indirectly ok.

the v\n works like the following. ( each gear has a defined tolerance band for ratio and a threshold band for the ratio!!)
when the ratio is with in a tolerence band the current normal gear is detected by ecu, when the ratio is in threshold band, then corresponding fast gear is detected .
and reverse gear will have a very unique v\n ratio not similar to any other gear ratio.
hope you guys understand.
so in a verna there should be GCU considering that its a new gen vehicle.
i guess the old cars with just ECU will be using the V/n methd.
so now i hope you guys know how the ECU gets to know which gear is selected and how the ECU differentiates between 2000rpm in 1,2,3,4,5 gears!!
peace out
sameel

Last edited by sameel : 30th June 2008 at 09:37.
sameel is offline   Reply With Quote
Old 30th June 2008, 11:36   #254
Senior - BHPian
 
Shan2nu's Avatar
 
Join Date: Feb 2004
Location: Hubli - Karnata
Posts: 5,525
Thanked: 87 Times
Default

So from what you're saying the torque produced by the engine at 2000 rpm (at the crank) in every gear is diff?

Anyway, even on the most basic of cars, the transmission would still see to it that the torque reaching the wheels is diff in all gears.

Shan2nu
Shan2nu is offline   Reply With Quote
Old 30th June 2008, 12:00   #255
BHPian
 
sameel's Avatar
 
Join Date: Jan 2007
Location: cochin
Posts: 268
Thanked: 3 Times
Default

yeah that is true, but for better co-ordination we made all the mechanical stuff to be more or less controlled by electronics!! . in the process the engine life is prolonged and also diagnostics of engine related troubles are more easy in current gen vehicles.
and the thumb rule as we all know is 1-5 gear, torque goes on decreasing,
maximum torque is in first gear..still in diesel engines with CRDi due to use of this ECU co-ordination, now a days the diesel cars are as good as the petrols when it comes to performance too. and this is possible due to this ECU co-ordination.

as can be commonly seen old gen diesel vehicles cant hold a candle to old gen petrol cars, but now its not the case
sameel is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hyundai Verna VGT: 50000 kms in 5 years. Pleasant experience at Trident Hyundai SantoshPV Long-Term Ownership Reviews 1 25th June 2013 14:50
Hyundai Verna CRDi VGT: Long Term Ownership Report live2drive Long-Term Ownership Reviews 49 12th April 2011 22:16
Just another love affair: Hyundai Verna (SX CRDI VGT) Lancer.ized Test-Drives & Initial Ownership Reports 66 24th September 2010 04:50
Hyundai Verna(VGT) test drive(torture drive) tsk1979 Test-Drives & Initial Ownership Reports 67 3rd October 2008 20:20


All times are GMT +5.5. The time now is 12:06.

Copyright ©2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks