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VTC Gears?

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Old 06-06-2007 | 08:59 PM
  #26  
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What a crock of sh*t....Find out which car that mechanic owns and **** into the driver's side window. It's just the springs.

Has anyone ever heard of a cam gear wearing out?
Old 06-06-2007 | 09:09 PM
  #27  
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Looked in the engine mechanical part of the FSM that I have PDF version. Couldn't find anything on it, only found one mention of VTC anything. Maybe I'm looking in the wrong part, wanna guide me? So far there is nothing I've not been able to find in a repair manual on the miata, but this is different.
Old 06-06-2007 | 09:18 PM
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There are 4 screws that hold the center cap on the the VTC CAMS. Remove the screws. The spring is right there. Take out the old spring, pop in the new spring and install new o-rings, then just put it all back together.
Old 06-06-2007 | 09:43 PM
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2nd. To elaborate a little: 4 small phillips screws on the intake cam gears. When removing the last two, apply some pressure so the covers and springs don't attack you.
Old 06-07-2007 | 04:49 AM
  #30  
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3rd, and to elaborate a little farther, you need to disconnect the PTU, CAS, & coolant temp sensors, and then remove the two upper t-belt covers.

But, don't forget, only do this after pissing in your mechanics drivers side window.
Old 06-07-2007 | 06:37 AM
  #31  
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Originally Posted by CanyonCarver
But, don't forget, only do this after pissing in your mechanics drivers side window.
**** first, removing springs later. Got it!
Old 06-07-2007 | 08:29 AM
  #32  
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Originally Posted by 91zxtt

Has anyone ever heard of a cam gear wearing out?
No, never, in any type of car.

Ever.
Old 06-07-2007 | 09:01 AM
  #33  
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It would be almost impossible. Especially in our cars, which don't use a chain operation. How could a piece of extremely strong metal be worn out by a rubber/metal belt?
Old 06-07-2007 | 09:57 AM
  #34  
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Originally Posted by 91zxtt
What a crock of sh*t....Find out which car that mechanic owns and **** into the driver's side window. It's just the springs.

Has anyone ever heard of a cam gear wearing out?
through the many motors i've had, and swapped, and rebuilt. never in my short life have I heard that.
Old 06-07-2007 | 10:52 AM
  #35  
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... and here's the kicker... if cam gears did wear out... would they tick?
Old 06-07-2007 | 12:15 PM
  #36  
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Actually, I have heard that the VTC mechanisms inside the cam gears do wear out. The cam gears don't normally get replaced when you do a rebuild, so I could believe that as a motor reaches the end of its second life, that the cam gears are pretty tired.
Old 06-07-2007 | 09:26 PM
  #37  
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Originally Posted by ZLover4Life
... and here's the kicker... if cam gears did wear out... would they tick?
on top of that....if they do tick, and nobody is around, does it really make a sound? Quite the mind bender....

Either way,...you still need to **** in the window.
Old 06-07-2007 | 10:17 PM
  #38  
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Originally Posted by 91zxtt
on top of that....if they do tick, and nobody is around, does it really make a sound? Quite the mind bender....

Either way,...you still need to **** in the window.
could you even hear a valve timing springs tick period??
Old 06-08-2007 | 02:10 AM
  #39  
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are you asking if you can hear VTC springs when they go bad? yes
Old 06-08-2007 | 11:48 AM
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Originally Posted by ZLover4Life
are you asking if you can hear VTC springs when they go bad? yes
Thanks!
I was scared there for a minute.

Geez people.
Old 06-08-2007 | 09:12 PM
  #41  
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when does VTC kick in 4.5-5k rpm's??
Old 06-08-2007 | 10:00 PM
  #42  
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I think it's sooner than that, but that's just an educated guess.
Old 06-08-2007 | 10:05 PM
  #43  
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cant hear the difference until about 5k in my car..
Old 06-09-2007 | 12:07 AM
  #44  
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maybe 3k rpms, but up until 6400rpms
Old 06-09-2007 | 12:24 AM
  #45  
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NVCS = VTC

Light Load
At light loads and below 6100 rpm, NVCS is OFF with the intake valves retarded. This helps to promote a smooth idle and engine stability.

Medium to Heavy Load, < 6100 rpm
At higher loads but lower RPM's, it is possible for air that has flowed into the cylinder to bounce back out again. This decreases volumetric efficiency and therefore an earlier valve closure is desired. So under these conditions NVCS is ON and the intake valves are advanced by 20 degrees. Doing this can increase engine torque in this range by close to 20 lb-ft.

Medium to Heavy Loads, > 6100 rpm
Now at higher RPM's, whereas before the problem was that air was bouncing back out through the intake port, now the problem is that not enough air has had a chance to flow in yet. In order to take advantage of inertia effects, a later valve opening is preferred, even if it is the same duration. So at high revs, NVCS is now switched OFF and the intake valves are retarded back 20 degrees to their original position.
http://www.twinturbo.net/net/viewmsg...msg_id=1843670
Old 06-09-2007 | 11:20 AM
  #46  
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Now i have to ask. Is there a VTC controller? like Hondas have?
Old 06-09-2007 | 12:54 PM
  #47  
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Only the ECU, I believe.
Old 06-09-2007 | 01:47 PM
  #48  
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probably, becuase honda's uses a solenoid sorta setup that releases oil flow to activate the V-tec lifters aka letting the larger cam lobe do its work, you can controll teh solenoid, this is just computer controlled, no larger cam lobes none of that, totally different method of function.
Old 06-09-2007 | 02:02 PM
  #49  
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just get bigger cam's....
Old 06-09-2007 | 08:07 PM
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i believe amz used to offer one. i couldnt find it tho
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