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Old 3rd January 2007, 22:02   #16
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and also upgraded brakes, a different suspension setup
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Old 3rd January 2007, 22:59   #17
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Quote:
and also upgraded brakes, a different suspension setup
I don't think they've been upgraded.

Shan2nu
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Old 3rd January 2007, 23:23   #18
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Can we forget that tacho!!!
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Old 4th January 2007, 03:04   #19
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and the rims and exhaust tips are different too
Quote:
Originally Posted by Mpower View Post
The cam does not move, there is a different lobe for every stage.

BMW's valvetronic technology moves the cam.

if cam does not move and lobe sizes are fixed, how are the valve timings varied??

Last edited by Mpower : 4th January 2007 at 07:03.
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Old 4th January 2007, 07:02   #20
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Quote:
Originally Posted by arctic View Post
if cam does not move and lobe sizes are fixed, how are the valve timings varied??
In a 3 stage VTEC there are 3 lobes for every valve and the lobes slide in and out using hydraulics. I am not sure about the details, you can search the forum.
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Old 4th January 2007, 09:26   #21
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The difference is not so much about the 6 bhp, as the 6 bhp wont make much of a difference in the real world (unless in flat out acceleration)... Nor, does it have much better mileage figures...

The difference is more so in the way the Vtec screams to the redline with ease... Vtec has got one of the best top- end in any of the indian cars... But, am pretty sure the 1.5 wont let you down too...

If you are into bikes, try riding the pulsar DTSi and apache... Although both have same power, you'll notice that the charecter of power delivery is very different... Apache giving same power within 6.5k rpm (If i remember rightly), and pulsar engine screaming to 10.5k rpm, which i feel is defenitly more fun for spirited riding... (Apache owner... Dont take this personally and attck me... Just my opinion)
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Old 4th January 2007, 10:03   #22
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Mpower,
In deed the cam does move in few of the VTEC engines. In Few of the VTEC models they introduced 2 lobes close to each other on the same CAM so that they can lock the valves at higher RPM's and use a different lobe to operate the same set of valves not sure of the Engine type (DOHC or SOHC). I have both the videos of VTEC for SOHC engine I'll upload share the link with the team.

An Article from Wiki
"Honda's VTEC system is a simple method of endowing the engine with multiple camshaft profiles optimized for low and high RPM operations. Instead of one cam lobe actuating each valve, there are two - one optimized for low RPM stability & fuel efficiency, with the other designed to maximize high RPM power output. Switching between the two cam lobes is determined by engine oil pressure, engine temperature, vehicle speed, and engine speed. As engine RPM increases, a locking pin is pushed by oil pressure to bind the high RPM cam follower for operation. From this point on, the valve opens and closes according to the high-speed profile, which opens the valve further and for a longer time. The DOHC VTEC system has high and low RPM cam lobe profiles on both the intake and exhaust valve camshafts."

Thanks "Pankaj" for correcting the mistake, Well I was actually so much occupied with work and wanted to reply to this post, I just took 2 mins and wrote the entire thing even without proof reading I just posted it It's why so many spelling mistakes.

Thanks,
Mega
"VTEC is the result of an effort to marry high RPM performance with low RPM stability" - Wiki
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Old 4th January 2007, 10:11   #23
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Quote:
Originally Posted by narayan View Post
does the 6bhp make such a big diff in 0-100 ?!! ( im depressed !)
Hey, don't be depressed!!! If you are a person who shifts up below 4500 rpm, I don't think VTEC matters to you. That's because VTEC kicks in above 4500 rpm (VTEC gurus...pls confirm).
Quote:
Originally Posted by narayan View Post
im really depressed by the fact that the 1.5 is always the underdog when compared to the VTEC for just that 6 BHP shortfall ( even considering putting a VTEC logo on the bumper
I remember reading the ACI first drive for VTEC long time back. They were saying something like this- "If 1.5 is a wild stallion, the VTEC reminds one of a thoroughbred racehorse". So be happy that you don't own a donkey. the 1.5 is a great car.
IMO, please don't try putting VTEC log and fake twin exhaust etc. It looks very naive.
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Old 4th January 2007, 10:49   #24
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It's doesn't matter what engine is under the hood when your driving a Honda or a Toyota they are the best cars and they are quite aware of what they are doing. The only place I feel that Honda Goofed up is the NHC Engine is good but they spoiled the looks as compared to OHC.

So Narayan don't be dishearted, Be proud that you own a OHC I'm J cause I couldn't find a good OHC 2nd hand so decided to buy Baleno new one.

One day may be I'll find a OHC whihc is as good as new and start my Mod Project even though I'm not an Auto Engineer neither Am I a Mechanic.

Thanks,
Mega
--Hoping to Find A OHC Looks as Good As New.
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Old 4th January 2007, 11:04   #25
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If it makes you feel any better, the 1.5 nukes the Vtec in the roll-ons (at low rpms).

The 1.5 has better driveability.

Shan2nu
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Old 4th January 2007, 11:27   #26
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I had the 1.3 OHC (always wished I had bought the 1.5) and I always felt that even in the 1.3 and 1.5, Honda had implemented some sort of differential valve / timing technology close to vtec. The reason I am saying this is because there was a such a huge kick, once the engine rpm crossed 3.5-4k, which was very much missing in any other car. Actually the vtec as Shan2nu said had poor driveability due to lots of jerking at low rpms. I do not think you really need to regret your 1.5 OHC at all.

If you want to read more about Honda's new iVtec tech. here are some links:
Honda Worldwide | New 1.8l i-VTEC Engine
Technical Overview of Honda's new R18 i-VTEC Implementation
http://asia.vtec.net/Engines/R18A/index.html

Last edited by sandeep108 : 4th January 2007 at 11:30.
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Old 4th January 2007, 11:57   #27
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In OHC VTEC the VTEC kicks in at 5200rpm.
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Old 4th January 2007, 13:23   #28
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Quote:
Originally Posted by Pankaj401 View Post
In OHC VTEC the VTEC kicks in at 5200rpm.
No wonder GTO is not letting go of his VTEC, in spite of having a great merc.
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Old 4th January 2007, 14:48   #29
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Quote:
In OHC VTEC the VTEC kicks in at 5200rpm.
I don't think it's that high. The Vtec produces 132nm@4700rpm. You can't have that sort of torque from a sedate cam profile.

So the Vtec must be kicking in at around 3500-4000rpm. It wont affect FE as we hardly cross 3000rpm when we're in economy mode.

Shan2nu

Last edited by Shan2nu : 4th January 2007 at 15:01.
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Old 4th January 2007, 15:22   #30
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this is the most detail explation of how a vtec works hop this will solve your problems.

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