Adjustable cam gear install.

[JimX]

I have one of those timing lights that shows up double what it really is. ie, 30 degrees when it's really 15. How would I go about setting it to anything higher than that? 30 is the highest marking on the crank.

[Guest Robo's]

Ive got one of the old timing light guns that the plug goes on number 1 lead. I havent seen any other guns. Is there??

[lukits01]

on the CAS which way is advancing and which is retarding?

after setting say 2 Deg retard on the cam gear

do you set the base timing back to 15 Deg?

[Jay95R33]

Thanks SydneyKid - that's exactly what info I was after. I'll be having a play with the timing next Wed when the car is having a play on the dyno.

Lukits01 - turning the CAS anti-clockwise will advance the timing. Is this right everyone? Or have I stuffed up the direction again... LOL

[Cecam]

Directions right... anti-clockwise does indeed advance the timing...

[Guest Robo's]

Yes Correct

[Warpspeed]

cannot really add much to what has already been said, but.........

The easy way to turn the engine over to exact TDC, or anywhere else, is to put it into fifth gear and roll the whole car backwards or forwards. Slop in the drivetrain allows you to bounce the engine. Try it, you will see what I mean. When it's there, put on the handbrake. Easy. If you have an auto, bad luck.

Another thing, fair enough you can retard it four degrees, but how do you know that the starting position was correct ? Also belt tension and belt stretch just by itself can shift it nearly that far.

Think about it, if the belt has stretched, and you tension in the belt a bit on the slack side, both cams retard by however much the belt has stretched. only a couple of mm is actually a fair way. One whole turn being 720 degrees.

To do it properly you need a dial indicator and degree wheel, and find out exactly where each cam is, and where it should be. It's a lot of work, and a pain in the arse, but its the only way to know for sure.

[Sydneykid]

Hi Warpspeed I am confused, the standard RB pulleys have marks which you line up for TDC of the camshafts. The crank also has a mark on the pulley for TDC. If these three marks all line up then the crank is at TDC, the inlet camshaft is at TDC and the exhaust camshaft is also at TDC. If the adjustable pulley is marked correctly then you can lock the camshafts at TDC and the adjustable pulleys should just slip on, when they are on zero correction. If the adjustable pulleys have marks for degrees and they are accurate, then you know the exhaust camshaft is 4 degrees retarded when it is on the 4 degree mark. No guesswork required.

Back in the old days we use to have to degree in a camshaft because the grinding was not as precise as it is now. I haven't found a camshaft in a Japanese DOHC multi valve engine that is not marked precisely for TDC for the last 10 years or so. Since we tune the camshaft position on the dyno it doesn't matter anyway, we adjust the pulleys to the point that makes the power curve the way we want it. So I don't care whether it is 4 degrees or 10 degrees on the pulley marks, it is where I want it that's all that matters.

Hope that helps

[Warpspeed]

Yes I agree, the cams themselves are pretty precise, and probably so are the gears and crank key. The problem is only with the belt.

If the belt is slightly longer on the tight side because it has stretched, and you take up the slack with the adjuster, then both cam pulleys will have rotated very slightly anticlockwise with respect to the crank. As far as the timing marks go, you can only really fit the belt one whole tooth out, and the error is pretty obvious. But what if it is just a fraction of a tooth out ? The timing marks will still look o/k. Would you actually notice 2mm ?

Not sure, but I think the cam pulleys have 48 teeth. that is 720/48= 15 degrees per tooth. 2mm of belt stretch (with an 8mm pitch belt) is one quarter tooth, or 3.75 degrees.

2mm belt stretch is not a lot between crank and exhaust cam over almost half the whole belt length, on a high mileage belt. Sure, the belt will be a bit loose, but tightening it back up could shift both cams by nearly 4 degrees.

If you really heave on the adjuster, you can actually see the damned things move ! I kid you not.

I am probably being a bit of an old woman about this, but people here are going to a fair bit of trouble and expense to do the 4 degree exhaust cam tweak, expecting to pick up measurable power. If the cams are maybe four (?) degrees out to begin with, the results may not always be quite as expected.

[whatsisname]

All the more reason to do the adjustment during a dyno session, as Sydneykid mentioned.

[lukits01]

Hey guys

my cam gears are finally here and Im about to try and install them, probably this weekend

been looking at the engine bay

was wondering how do you take off the Cam gear covers off?

how many bolts are there and roughly where are they located?

[EnricoPalazzo]

i did this today using the methods from jay and blind elk. Thanks heaps dudes!!!!!!!

[devious17]

six bolts all together.

Two hex keys on either side ,three 10 for the CAS and one 10 below the CAS,slightly to the center of the cover.

[EnricoPalazzo]

hahah i lost one nut from the cam cover belt. It just disappered And the worst thing was that it was the last nut i was puttin back on. Then trying to find the thing took longer then what it took to install the cam gear. It was really easy, thanks to all the help from everyone. Its gettin tuned tomorrow.

[lukits01]

thanks guys cam gears installed and working

awesome stuff

hit full boost by 1000 RPM ahhaha

just a note there are actually 8 bolts on the cam cover

hey when setting the base timing to 15 Deg is it on the 3rd white line after the first orange line? and what RPM should the timing be done at?

[benm]

My Trust Ex Cam Gear arrived yesterday from Nengun (13,000yen + Shipping, took 2 business days to arrive). I just re-read over this entire thread to see if i'd be able to do it myself and it was an absolutely comedy haha.

I was going to ring UniGroup this arvo and ask them to do it (I want a before/after Dyno run) but $160 is pretty rich, i'd happily pay $100 for it if its only a 30min job but $160 makes a cheap mod into an expensive mod.

Hey JimX... :bananaman

[EnricoPalazzo]

dude it is so easy, just do it urself. I would do it for u if i was in sydney

[armbrusb]

Hi JAY95R33/ JIMX,

Did retarding the ex timing make the car feel any different?

[Jay95R33]

Hi JAY95R33/ JIMX,

Did retarding the ex timing make the car feel any different?

Do you mean "did retarding the exhaust cam gear make......."

Then yes, as said earlier on in this thread, I found retarding the exhuast cam gear by 1.5 degrees (3 degrees crank angle) gave me an improved mid range.

Cheers

Jayson

[benm]

I will hopefully be getting mine fitted/tuned this Wednesday.