Adjustable cam gear install.

[JimX]

The final results are that it's in and working - on zero degrees The reason being that when I tried -3 and -4 degrees, I got a noticable drop in power. I also got the maximum injector warning on my PowerFC hand controller, so it could just be because I don't have enough fuel for the extra power. But it also could just be that the timing is so adversely affected that I'm just maxing out the injectors and losing power at the same time.

So I put it back to zero degrees and it now awaits a tune. I am waiting for my Z32 AFM to arrive from Germany, and I will then put that in along with my 550cc injectors, and then get the workshop to set the gear to whatever works best. If it ends up on 0 degrees, I will remove it and put the factory one back in and sell the adjustable one.

[benm]

..to me !

[Guest Robo's]

I wont divulge the name, but yes they are the factory one been modified. I'll throw it on tonight anyway.

[Guest Robo's]

Ok just put it on, now this is what i done, correct me if im wrong.

With no cam gear markings, only centre, the cam gear is 360 degrees, and has 48 teeth, so each teeth represents 7.5 degrees, so i adjusted it too half a tooth, say 3.75 degrees. I adjusted it clockwise. Does this sound right???

Now, looks like i have to get a new timing light as i can't connect anything to that white lead, but im getting a lot of ping, so im doing the old trick, advance until it pings, and then back it off slightly.

[Jay95R33]

Ok just put it on, now this is what i done, correct me if im wrong.

With no cam gear markings, only centre, the cam gear is 360 degrees, and has 48 teeth, so each teeth represents 7.5 degrees, so i adjusted it too half a tooth, say 3.75 degrees. I adjusted it clockwise. Does this sound right???

Now, looks like i have to get a new timing light as i can't connect anything to that white lead, but im getting a lot of ping, so im doing the old trick, advance until it pings, and then back it off slightly.

BAD BAD BAD..... For every 1 degree on the cam wheel, it's 2 degrees crank angle !!

So in my case I was aiming for 3 degrees crank angle retard, so I adjusted my cam gear to 1.5 degrees retard...

So if you adjusted yours to about 3.75 degrees on the cam gear then your running about 7 degrees retard !!!!

J

[Guest Robo's]

Hmm, looks like i stuffed it up, as when i think about it, i advanced the dowel which is connected to the camshaft, not the cam gear, the cam gear stayed still. i wonder why ive lost all my bottom end.

Ohh well, back off tonight, should be easier now.

[Guest Robo's]

Ok, all done now, adjusted it back last night, hmmm i like the power now, time for another squirt down the quarter, looking for a 13.2.

[dojobi]

Do you guys have a dyno sheet of your cam gear installs? I had a flat power curve before I put mine on (no dyno sheet to post up of that sorry), but afterwards when I had it set to 4 degrees retarded I got a decent power dip when the NVCS kicks in and a stronger top end. Before the retardation, I couldn't feel the power dip, but now I can. If you look at my torque curve, it's not too impressive at all.

Here's my dyno sheet (big file, sorry) - http://members.ozemail.com.au/~caddies/MIC33Rdyno.JPG

So basically, I guess what I'm asking is, Were you guys able to tune the dip out with a decent ECU like a Power FC, and is it worth my while to remove the gear from my 33 with a Super AFC (where I feel it hurts the drivability) and put it into my future 34 with a Power FC? I was planning on selling it with the car.

[Jay95R33]

Before you get a re-tune to try and get rid of the dip, change the cam gear to 3 degrees retard (1.5 degrees on the cam wheel) and see how that goes.

Generally (changes depending on setup), 4 degrees will give you more top end, while 3 degrees will give you more mid range.

I opted for 3 degrees cause mid range is where it's all at for me

[dojobi]

Jay, I'll be selling the car soon, so I probably won't change the cam gear except to remove it (if it's worth keeping). If I wasn't selling it, I'd definitely do the 3 degree change.

I asked them about the dip when I first got it tuned, and they said it's a pretty standard graph for a car without an ECU that can control ignition timing. They said if I want to have it tuned out I'd need something like a Power FC.

So I'm just tossing up whether or not I should keep it for my next Skyline (which should be this year).

[lukits01]

When removing the Crank Angle Sensor (CAS), how do you make sure its in the same place when you put it back on?

in other words, where do you mark it before you remove the CAS?

Anyone got a picture of this?

[Sydneykid]

Hi MIC33R, when you retard the exhaust camshaft timing (with the adjustable pulley) you retard the base ignition timing as the CAS is connected to the exhaust cam. You then correct this by advancing the CAS in its slots. What the workshop told you is similar to our experiences, the retarded exhaust timing needs a bit more ignition advance to work best. This is particularly noticeable when the engine is building boost. Hence the dip in your power graph.

As for keeping the adjustable exhaust pulley when you sell the car. As I see it, the question is will you get more for the car with it or without it? And will the difference be enough to buy a new one for your next Skyline? Or will the cost of removing it out way the benefit?

Hi Lukits01, I use a marker pen and put a line where the bolts are in the CAS slots.

Hope that helps

Hi

[Jay95R33]

G'day SydneyKid,

Just wondering if the change (retard) of timing, when you retard the cam gear, is noticable in a change of base timing with a timing light?

I'm just thinking that once the cam gear has been retarded, is it best to check the base timing and set it to what ever it was, or back to the stock 15 degrees advance, seems that if you line it back up with the mark you put on the CAS it'll now be a touch retarded.

Thanks

J

[dojobi]

Thanks for the info Sydneykid. I feel it won't really add much to the value when I sell it, but the cost of paying someone else to take it out is fairly high and would probably be more than it would add to the price. I think if I removed it myself (which I am a little scared of doing), it would be worth it. It's something I'll have to think about.

[JimX]

MIC33R, I was scared of doing it myself too. Read back in this thread and see for yourself! But once I listened to enough advice about other people doing it, I decided to give it a go and I'm glad I did. Once you've done it for the first time, you should be able to do it again within half an hour if you want to swap back again for whatever reason.

[dojobi]

I've just heard a couple of horror stories before, that's all To get to it I have to remove my intercooler piping too (which i will be doing anyway), so I could just do it then.

[Guest Robo's]

Im quite confident now in doing it, the time consuming bit for me is getting the timing right, as i dont have the proper timing light gun, i have to go until it pings then retard it a little, although i think im nearly spot on.

[lukits01]

Im quite confident now in doing it, the time consuming bit for me is getting the timing right, as i dont have the proper timing light gun, i have to go until it pings then retard it a little, although i think im nearly spot on.

is that the timing at the cam gear or at the CAS?

what was your final settings anyway?

[Guest Robo's]

We took about - 2 degrees off the exhaust cam gear and therefore had to advance the CAS, otherwise it was running like a dog. Put some timing into it though, and she comes back to life.

[Sydneykid]

Hi Jay95R33, I always check the ignition timing with a timing light and adjust accordingly. The marks on the CAS mount are only there as a point from which initialise the CAS adjustment. Otherwise, I have no idea where to start. I can also observe how much I have to rotate the CAS to get back to where I started from, from an ignition timing point of view. I have had occasions where this audit check shows up other issues (eg; worn locators in the CAS).

Hope that clarifies