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Old 26th August 2010, 18:26   #16
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Originally Posted by dhanushs View Post
Different speedo readings during the same run leads me to believe that you've got a faulty tacho/speedo. Please check if these are OK.

Difference in engine bay temperatures may sometimes show a slight difference in vehicle performance, but, then showing different speedo readings for same rpm - I dont think so.

Again, a worn out clutch can have the above said effects. The best symptom of a worn out clutch is that, on some extreme situations (like trying for a wheel spin on a tarmac with loads of grip) you sometimes feel your car is not traveling enough for the amount of pedal, ie, the engine would simply rev without transferring the torque to the gearbox/wheels. Also, there will be a noticeable drop in FE. Please check it out. - Experts please add to this.
Ok but I'd really be gratefull for a way to physically check things out. I'll try a wheelspin tomoro =)
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Old 26th August 2010, 19:10   #17
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if you are sticking to the second gear upto 90+ speeds, I doubt you clutch plates will have any issues (provided there is no slip), engine however is a different issue.
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Old 26th August 2010, 20:01   #18
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Prob just a worn out speedometer. My car used to read 70kmph@2000, now it reads 74kmph. The speedometer unit has worn out. Costs 2,300 to replace@honda.

But you can prob get it fixed for peanuts if you give it to these speedo repair guys outside.

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Old 26th August 2010, 20:29   #19
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Originally Posted by di1in View Post
Is that muck buildup near the top of the headers a sign of somethin bad?
Ideally there should't be any. But a little oily appearance is OK.
Looks like you have a worn packing. Its a rubber packing and can be replaced within 5 mins or so. Around 400/- for the thing.

EDIT : Its unlikely, still see if the oil level drops over time, say 1000kms. If so better do it. Else if you can live with an oily engine bay..

Last edited by yzfrj : 26th August 2010 at 20:30.
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Old 26th August 2010, 20:43   #20
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Originally Posted by di1in View Post
Considering the way people (like me) drive after gettin hold of a ffe, there won't be much left of the clutch. its the exhaust note that my right foot is addicted too..



What kind of alterations?

Is that muck buildup near the top of the headers a sign of somethin bad?
The muck buildup near the head is a clear sign of Head gasket wear out.

Even this affects your cars running, especially with such a precise engineering such as Honda cars.

Get that done ASAP.
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Old 26th August 2010, 21:18   #21
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Quote:
Originally Posted by Shan2nu View Post
Prob just a worn out speedometer. My car used to read 70kmph@2000, now it reads 74kmph. The speedometer unit has worn out. Costs 2,300 to replace@honda.

But you can prob get it fixed for peanuts if you give it to these speedo repair guys outside.

Shan2nu
I'll do a run and check out the speedo with a gps and post the results here tomorow morning.

Quote:
Originally Posted by yzfrj View Post
Ideally there should't be any. But a little oily appearance is OK.
Looks like you have a worn packing. Its a rubber packing and can be replaced within 5 mins or so. Around 400/- for the thing.

EDIT : Its unlikely, still see if the oil level drops over time, say 1000kms. If so better do it. Else if you can live with an oily engine bay..
The oil levels haven't dropped but there's a lot of this stuff and there's grit too.

Quote:
Originally Posted by PAVAN KADAM View Post
The muck buildup near the head is a clear sign of Head gasket wear out.

Even this affects your cars running, especially with such a precise engineering such as Honda cars.

Get that done ASAP.
I use a free flow, could that be the reason? I had it installed at Ostlers, Kochi. It's the Raj type, but I've read a lot of complaints about the one's shabeer made. Is there any particlar type of gasket that i ought to use so that this problem doesn't creep up again?
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Old 26th August 2010, 21:26   #22
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Quote:
Originally Posted by di1in View Post
I'll do a run and check out the speedo with a gps and post the results here tomorow morning.



The oil levels haven't dropped but there's a lot of this stuff and there's grit too.



I use a free flow, could that be the reason? I had it installed at Ostlers, Kochi. It's the Raj type, but I've read a lot of complaints about the one's shabeer made. Is there any particlar type of gasket that i ought to use so that this problem doesn't creep up again?
Use the original factory ones, they will last better than after market ones.

NO....! your FFE is no way related to this issue.

I too am not happy about the FFE set-up coming out of Raj's place, off-late, many of my friends are cribbing over his installs.
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Old 26th August 2010, 23:09   #23
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Originally Posted by Shan2nu View Post
Prob just a worn out speedometer. My car used to read 70kmph@2000, now it reads 74kmph. The speedometer unit has worn out. Costs 2,300 to replace@honda.
Shan2nu
so how much does ur ohc read after replacing the speedo @ 2000rpms?
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Old 27th August 2010, 09:13   #24
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Exclamation

Checked the car today morning:
40 @ 3rd gear @ 2000rpm
70 @ 5th gear @ 2000rpm

And the GPS check showed that the speedo is perfectly correct. I'd read somewhere that the OHC speedos had a +3.5% error built into them and I'd never believed that until today. Seems my -3.54% upsize error cancelled of the hondas error and I ended up with an accurate speedo.

Which brings us back to square one.

Could someone find time to post the real tacho vs speedo readings please? I'd like to know if the speeds at all rpms have changed or whether it's only at higher rpms or higher speed/load.
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Old 27th August 2010, 10:51   #25
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I calculated between 2 different calculators and it gives me 3.54% exactly between 195/55/15 and 175/70/13.
195/55/15
Radius = (195*0.55) + (15*25.4mm) = 488.25mm

175/70/13
Radius = (175*0.7) + (13*25.4mm) = 452.7mm

Note that 25.4mm is same as 1 inch.

So the change in radius is = (488.25 - 452.7)/452.7 = 7.8%

Circumference is directly proportional to radius. So the rolling distance will change in the same ratio.

I dont think u have any other problem other than tyre change.
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Old 27th August 2010, 12:37   #26
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Originally Posted by di1in View Post
..
And the GPS check showed that the speedo is perfectly correct. I'd read somewhere that the OHC speedos had a +3.5% error built into them and I'd never believed that until today. Seems my -3.54% upsize error cancelled of the hondas error and I ended up with an accurate speedo.

Which brings us back to square one.
..
Quote:
Originally Posted by pkumar View Post
195/55/15
Radius = (195*0.55) + (15*25.4mm) = 488.25mm --> a tire with a radius of 48 cms means it has a diameter of almost a meter!

175/70/13
Radius = (175*0.7) + (13*25.4mm) = 452.7mm

Note that 25.4mm is same as 1 inch.

So the change in radius is = (488.25 - 452.7)/452.7 = 7.8%
Like i said the speedo is working fine, so i actually am going at 70. I've attached 2 screenshots of tire size calculators which shows 3.5% difference, so there's obviously something wrong with your formula. The 15" inch given on a tire is its diameter and not it's radius, that is why your difference percentages were inflated. You probably got confused by the R in 175/70/R13, it stands for radial not radius.

Anyway it's not a speedo error that we're seeing here in my car. Something else is wrong and I'd like to find it.
Attached Images
  

Last edited by di1in : 27th August 2010 at 12:51.
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Old 27th August 2010, 14:05   #27
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Quote:
I'll do a run and check out the speedo with a gps and post the results here tomorow morning.
Dont use a gps device, coz even working speedos tend to be a bit off.

Connect an on board diagnostic device to the ecu and see if the speedo reading matches the speed reading on the ecu. The diff between the vss reading and speedo reading is what you need to look for.

Before the speedo problem, my speedo used to be bang on, but now it reads 74kmph@2000 in 5th on the speedo, while the VSS reading shows 70kmph.

But if you find that your vss reading has also changed after the FFE mods, then it could be a vss prob. (Since you've mentioned that the speedo was showing 80kmph@2000 even after tyre upgrade)

Shan2nu


Quote:
so how much does ur ohc read after replacing the speedo @ 2000rpms?
I haven't replaced the speedo unit as yet.

Last edited by Shan2nu : 27th August 2010 at 14:10.
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Old 27th August 2010, 21:26   #28
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Originally Posted by Shan2nu View Post
But if you find that your vss reading has also changed after the FFE mods, then it could be a vss prob. (Since you've mentioned that the speedo was showing 80kmph@2000 even after tyre upgrade)
I have no idea about my pre-FFE speedo voltage.

Would you remember how much your speedo read before the speedo problem. Was it 70?
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Old 27th August 2010, 23:21   #29
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Originally Posted by dhanushs View Post
Different speedo readings during the same run leads me to believe that you've got a faulty tacho/speedo. Please check if these are OK.
The above discussions, leads me to strongly suspect your speedo. and just like Shan2nu suggested, get it fixed outside A.S.S for cheap, or you could go to A.S.S and change the unit. But replacing the unit may reset your odo.
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Old 28th August 2010, 00:51   #30
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Quote:
Would you remember how much your speedo read before the speedo problem. Was it 70?
Yup, it read 70kmph@2000rpm in 5th. ECU still reads 70kmph, but the speedo shows 74kmph.

Even the calculated speed wrt engine speed, wheel size and gearing is 70kmph.

engine speed / gear ratio / final drive ratio x wheel circumference (inches) x 2.54 / 100000 x 60 = vehicle speed (kmph)

2000 / 0.774 / 4.058 x 72.8 x 2.54 / 100000 x 60 = 70.64kmph

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