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Thread: Cam timing.

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Posts: 11-20 of 37
2009-01-06 23:16:55
#11
The 3 different cam gears are probably these:
13024-53J01 Cam Gear SR20VE P11/Y11/U14 (also used on SR18/20DE and DET S13)
13024-1N501 Cam Gear SR16VE (B14,B15,N15 & N1)
13024-8H600 Cam Gear P12/T30 SR20VE/VET (due to different chain)

N1 only had Nismo cam gears along with Nismo cams as an alternative but not for the general puplic.

Have a look on this photo regarding chain setup


Now look how my SR16VE.N1 is set

The cam gear dot on the exhaust cam is on right screen corner


Exhaust cam has 45 marked on it

This was not done by me. It is found like that. I'm not sure if it was done in Japan or some teeth slipped due to tensioner replacement.
2009-01-06 23:37:12
#12
I disagree with that second pic.

Where is the dot on the intake cam.

When lining up these motors they will always line up with the dots under the colored links at the same time. If you turn over the motor enough and you did not do so.

Even the manual tell you so. If you even look at the pics from the manual you will see what I am talking about.

The motor is no lined up via a true mechanical TDC.


This stuff is alot easier than you guys make this out to be.
2009-01-06 23:49:01
#13
Originally Posted by Andreas
I disagree with that second pic.

Where is the dot on the intake cam.

When lining up these motors they will always line up with the dots under the colored links at the same time. If you turn over the motor enough and you did not do so.

Even the manual tell you so.

The motor is no lined up via a true mechanical TDC.


No kidding. There is no way that could be TDC. You can locate the dot based on the dowel pin (slightly clockwise from dowel).
2009-01-06 23:53:05
#14
This pic below is the answer to everyones cam changing jobs and understanding cam timing. If everyone would setup their motor as in the pic, cam intallment jobs would go easy.

The pic shows a true mechanical TDC.

True mechanical TDC occurs when the 2 colored links are over the 2 dots on each cam sprocket at the same time. When this happens ylu can look down at the crank pully and the timing maker will be over the 0 groove on the crank pully

To get a true mechanical TDC you have to spin the motor over untill both colored links are over the 2 dots. This means you might have to spin the motor over atleast 40 times depending where you are in the rotation of the motor.

2009-01-06 23:55:40
#15
Originally Posted by wnwright
No kidding. There is no way that could be TDC. You can locate the dot based on the dowel pin (slightly clockwise from dowel).



Thats the problem some people cant even folow pictures.

This is where so much misinformation comes from on the forums as people truely dont understand what they are looking at.
2009-01-07 00:03:15
#16
Originally Posted by Andreas
Thats the problem some people cant even folow pictures.

This is where so much misinformation comes from on the forums as people truely dont understand what they are looking at.


I couldn't agree with you more. This is why I don't post much. It is truely amazing how much misinformation some people will post (jer_760 and I have long conversations about this).

Maybe I will take pictures so you can do the write up. I have my VC off and everything assembled just sitting there waiting for me to stop being lazy.
2009-01-07 00:24:26
#17
Oh Andreas and I had a short conversation about the main contributor yesterday.....


I never take the time to rotate the motor until the marks line up, but then again I have done this probably 50 times. People that are doing this for their first few attempts definetly should not be taking the lazy way out.
2009-01-07 00:49:18
#18
Originally Posted by jer_760
Oh Andreas and I had a short conversation about the main contributor yesterday.....


I never take the time to rotate the motor until the marks line up, but then again I have done this probably 50 times. People that are doing this for their first few attempts definetly should not be taking the lazy way out.


Agreed!

When I had my new engine built the builder took FOREVER to check, double check, triple check, and then check AGAIN that these dots, and marks all corresponded with what the FSM said. I think that he turned it over more than I have! AHHAHAHHA! And he does this for a LIVING at Nissan!

He said that there have been too many issues with people who think that they can 'cheat the timing' only to find that Nissan ARE an interference fit motor, and don't much like the valves and pistons meeting at high speeds; made WORSE by the additional set of high lobes that force the valves in there longer and further (sounding like a porn HAHHAHAHAH!)

I'm gratefull that this engine builder knew his stuff, and stuck to his guns, as I felt reassured that reinventing the wheel and playing with static cam timing wasn't the way to get longevity out of the motor.
2009-01-07 03:23:39
#19
I just leave it to my tuner to actually play around with.
Took them a while to work out the way JWT gears need to be set.

I just like to know the theory behind what differences changes make
2009-01-07 04:35:47
#20
Lonewolf it's amazing that it took them so long to figure these things out.

I honestly think you could do this stuff yourself in your driveway/garage.


I think the most difficult thing about VE's is that most people aren't degreeing non-stock cams. With 16ve cams and N1 cams you can get away with throwing them in and setting the timing with adj gears but anything that is not a factory cam (even if they are copies of factory cams) need to be degreed. You can very clearly see centerlines and true lift and duration. Combine those numbers with your cam gears you can tune the cams to make pretty close to optimal power once and play around with ignition timing on the dyno.

I think there could be a lot better collaboration with the Aussie/Kiwi guys and us over here in the US.
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