Jump to content
SAU Community

Recommended Posts

Hi I have just been looking at my new exhaust cam gear and want to confirm something.

firstly i have searched and come up with nothing.

Please correct me if i am wrong...

1. RB20det cam gears rotate clockwise...

2. The cam gears have markings saying RETARD is the the left

3. If you rotate the blue center piece to the left effectively you are actually moving the cam to the right or clockwise

4. Seeming as the motor rotates clockwise this would mean infact you are ADVANCING the cam

5. Therefore the markings on the cam gear are WRONG.

can someone please confirm this. Picture below.

http://www.skylinesaustralia.com/forums/in...st&id=71726

If this is correct why? and if not could someone please explain?

Thanks all :ninja:

jeebus,

how can a product be engineered to a level of 0.10 tolerance and cad designed and milled to such a high standard and have backwards bloody markings?!

I am starting to wonder if the actual markers represent 2deg each..

i suppose at the end of the day it doesnt really matter, as they should be setup on the dyno, and then you record what the settings are, but yes a bit strange. interestingly enough it says crankshaft degrees, so in theory they are correct because instead of advancing the cam, you are retarding the crank relative to the cam.

Yep :D but if you look at the cam gear if you moved it to the left the markings would say it was advanced :P

weird huh.

as adriano pointed out it is crank adv or retard. still... a silly marking method.

thats what you get for being chap and american! no japs have designed these. americans drive on the wrong side of the road anyway so the probably andvance and retard there cams wrong to. haha

You always work realative to the crank position. So if you loosen the bolts and move the cam anticlockwise you are moving the lobe centerline of the camshaft to the left, meaning the cam is now retarded as it takes longer for the valve to reach the same lift relative to the same crank position. ie the lift at TDC will be less with a retarded camshaft and greater with an advanced camshaft.

So they have machined the A and R in the right direction.

why do Tomei, Greddy, Nismo and HKS have markings in going in the opposite direction?

not trying to be argumentative...

Do they - havn't seen that. It does depend on wether the advance or retard is on the section of the cam gear that is fixed to the cam or on the outer ring that is not fixed to the cam. Maybe thats where your being confused???? Its a little ambiguous. Its a hell of alot easier to think about camshaft postion relative to crank position.

Wait until you try to dial in a BA XR8 - 4 camsahfts four cam chains.

Edited by rob82

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I swear at my GKTech ones every time I have to take them apart and replace a spherical. But I wouldn't swap them for anything else. They absolutely slay every other option, at least in terms of how they actually work. You sure you don't want to live with bearings? I mean, they don't have "ball bearings". They are rod ends and sphericals throughout. Tough as nuts, even though I have found more than one way to wear them out.
    • From when I was looking at getting the 86 engineered for the turbo, the joint said to put in a few euro 5 or 6 cats, then tune the car on a nice clean E85 tune When I was looking at a turbo for the MX5, it was basically the same thing, a couple of cats and a nice clean tune Although, it will depend on the year of the Jeep IRT emmisions standards required, and what mods are done, especially if it has a newer engine installed that requires a higher Euro
    • Yeah - but it's not actually that easy. There are limits for HC, CO, NOx and particulates. Particulates shouldn't be a concern in any petrol engine unless trying to comply to the very latest Euro standard. But getting a tune right so that all the others stay within limits AT THE SAME TIME is not a trivial exercise. You couldn't possibly get it right by just guessing at the tuner's dyno, unless he had a 4 gas analyser up the pipe, which is not often the case these days. It used to be. Every decent shop that did "tune ups" (as opposed to tuning) would have a 4 gas analsyer. Perhaps there's still quite a few of them around these days. But most "tuners" are only watching O2 and power readings.
    • Slight segway but the most expensive part of the whole thing which I would have thought would only be required for an engine size/type swap, not a VIV test, is emissions testing.  That's when you get into the big bucks.  I can't remember the exact price now but I got quotes for the GT-R based on swapping to RB30 (not that anyone bothers doing it legally anymore...) and it was around $4500 just for that alone.  The guy that does them manipulates the tune on the vehicle to make sure it passes.  The cheaper option is to book into Kangan Batman Tafe (I think that's where it was) and hire their tester.  Allegedly you're not allowed in there with the car though so not in a position to tweak anything to make sure the vehicle passes.  I'm sure in this day and age of ultra tuneable ECU's you could get the tuner to program a special efficiency (clean) tune that emits the lowest amount of particulates possible that would pass the test.  It might only make 50kW's but as long as it passed who cares!
    • I'm sure he has left signs, or, he is looking down, laughing That's my cunning plan for when I leave, lots of half finished projects, with no rhyme or reason of where I was actually up to, just to keep everyone on their toes
×
×
  • Create New...