Rb25 Neo Exhaust Cam Gear Question

[mick-r34gtt-]

I will post pics soon. BUT in mean time I took the covers off my other r34 and the timing marks are the same-1 tooth clockwise out so it must be like that for a reason as if I put adjustable cam gear on you can adjust it there so I'm gunna put it back to a tooth out and see if my car runs good again so I shall let you know if all good.. Cheers

[Shoujiki]

That is very interesting! When i did all of mine, the belt looked like it had never been changed, so that's why I was skeptical it was an error by someone else. Looked all Nissan factory. Haven't started mine yet, so would be keen to see what happens!

[iruvyouskyrine]

Pics. Pics pics pics.

[mick-r34gtt-]

Iruvyouskyrine what pics would you like as mine before I did the belt change mine looked exactly the same as the pics that are on this thread and that's how I will be putting it back to but at moment I've got all timing marks spot on the marks. Even my cas was in same place as pics already posted...it must be like that from factory (1 tooth out clockwise) as even my other 34 is the same and that 34 only has 62000 on clock and has not been changed.. I will post again soon and let ya know how things go when I put it back to a tooth out!!! But I think problem solved... HOPEFULLY...

[mick-r34gtt-]

Yipee all good now!!! I set it back to a tooth out and as I thought it's all good running perfect... I'm rapt...

[Shoujiki]

Hah! Well that's not very good for me Good thing I haven't finished the engine yet.

So just 1 tooth forward on the exhaust and all is well? Could this really be a factory Nissan thing? Even though the FSM states to line the marks up.

Surely someone else here has done a 34 timing belt? Anyone else seen this?

[XKLABA]

Mick, so you turned the exhaust cam retarded by 15 deg but put the CAS back how it was before you started ?

So the ignition timing and injector timing is 15 deg retarded

Or did you reset the base timing ( CAS ) to factory spec with a timing light

A change like this with a tuned ECU chip would very least require a run on the dyno to make sure it's ok still

[mick-r34gtt-]

Hi xklaba, yeah I put the cas back to were it was b4 roughly in center and it's running perfect. I'm putting the timing light on it tonight after work and it's booked in for a dyno tune as I'm putting a power fc inplace of the nistune also putting all my plazmaman stuff and going bigger injectors. Will keep this post informed but it is weird that even my other 34 is a tooth out aswell and my other 34 is stock. I'm just glad it's running perfect again can't wait for the dyno tune as last time it pulled 371.1kw anyway I will let ya know how the timing is later. Cheers

[Ben C34]

I'm calling no way was either car a tooth out.

You are looking at it from some crazy angle.

[XKLABA]

When you get it on the dyno change the cam timing to where it should be and reset CAS timing to factory spec them run it up, 15 deg retarded on the exhaust cam will make a massive difference to how the car drives

[mick-r34gtt-]

I took pics of it being the tooth out I will post when I get home and that's how it is now. My mate helped me with doing it and he owns cylinder head and development so I think we ain't looking from any crazy angle and even he spun out about both my 34's being out.. if ya anywhere near Geelong Victoria you are more than welcome to come look it over.. 1 car is stock and my other has abit of work like tomie cams, 800cc injectors and about to go bigger,nistune type4 board, hiflowed Garrett turbo, Spitfire coils plus lots more and about to get more done and at moment 371.1kw ain't to bad...

[Shoujiki]

Ben, Check out my pics of my timing belt. I took them both at the same angles. No way it's a crazy angle causing parallax error. I took the photos from straight on, you can clearly see it was 1 tooth clockwise on the exhaust. And the thing was my motor didn't look like it had ever had a major service done.

Really hard to say what to do! Because I have mine set in the "lined up" position now, and i'm unsure if I should change it back!

[GTSBoy]

Best bet for all who are concerned would be to call a performance workshop that has built a lot of RBs and find out what they know.

FWIW, another thought I had is that for anyone who had their ECU tuned with the cam timing a tooth out, it probably WOULD run worse if you put the timing right but left the tune "wrong".

Edited November 13, 2015 by GTSBoy

[Shoujiki]

Mick I know you said you other car was stock, but does it by any chance have some type of piggyback ECU? Like a daughter board? You'd have to open up the ECU and check.