Author Topic: Camshaft timing question  (Read 2741 times)

Gabs

  • Full Member
  • ***
  • Thank You
  • -Receive: 0
  • Posts: 108
    • View Profile
Camshaft timing question
« on: March 07, 2013, 10:41:34 PM »
I came across this thread today, mentioning camshaft timing pins.


Now my question, I recently purchased gently used camshaft gears from bmwm42. When they arrived I noticed one of (for lack of a better word) half-pillar things was missing. After reading the thread above, I'm now thinking this is what was referred to as the timing pins, is this correct?

If so, does the camshaft sensor read both of these cam pins? Can I make use of the gear missing a pin? Pictures below.

Wanted to avoid posting large res pictures, links:
Gear Image 1
Gear Image 2

wazzu70

  • Nasty Nick
  • Hero Member
  • *****
  • Thank You
  • -Receive: 18
  • Posts: 671
    • View Profile
Camshaft timing question
« Reply #1 on: March 07, 2013, 10:59:43 PM »
The cam sensor just reads off one of the cam gears.

I'll double check my spare set and see if they both have pins or not. I can't recall off the top of my head.
-Nick
91 E30 M42 with VEMS

5m1dy

  • Newbie
  • *
  • Thank You
  • -Receive: 0
  • Posts: 38
    • View Profile
Camshaft timing question
« Reply #2 on: March 07, 2013, 11:33:41 PM »
If you are careful you should be able to push the pin out from behind on one of your old gears and replace the pin on the new one.

Probably worth using some glue/adhesive of some kind to help hold it in.

Gabs

  • Full Member
  • ***
  • Thank You
  • -Receive: 0
  • Posts: 108
    • View Profile
Camshaft timing question
« Reply #3 on: March 07, 2013, 11:42:22 PM »
The ones I pulled off my cams had pins on both.

I figured as much, since the cam sensor is so far off to one side (Picture Below). Looks to me it takes read off of the exhaust cam, ill have to keep that in mind when reassembly begins.




Since we've got that all wrapped up, I also read over someones post stating they had the head shaved a certain amount to lower compression. Looking to gather opinions on, shaving the head vs Using a cometic gasket to lower compression.

Reason I ask is I'm in the early stage of a turbo build, the bottom end should be finished any day now and I will be taking the head to the machine shop next week. Aiming for a modest 10-12psi boost, which method of lowering compression is the best route?

Edit: Not a bad idea 5m1dy, I didn't know they could be removed. I think ill leave it be to save the hassle, and just make sure I use the one with a pin on the exhaust camshaft.
« Last Edit: March 07, 2013, 11:44:52 PM by gabskee »

Nelson_40

  • Full Member
  • ***
  • Thank You
  • -Receive: 1
  • Posts: 122
    • View Profile
Camshaft timing question
« Reply #4 on: March 07, 2013, 11:56:18 PM »
You should just use the gear that has the pin on the exhaust cam and not bother swapping pins. Just for clarification, both gears should have pins, but the intake one is not really necessary.

As far as compression, shaving the head raises compression. Outside of a rebuild using different internals (which is the best way) a MLS gasket will work. What sort of internals are you running, or was the rebuild just stock + the 360 bearings you mentioned elsewhere?

wazzu70

  • Nasty Nick
  • Hero Member
  • *****
  • Thank You
  • -Receive: 18
  • Posts: 671
    • View Profile
Camshaft timing question
« Reply #5 on: March 08, 2013, 12:32:53 PM »
Quote from: Nelson_40;120822
You should just use the gear that has the pin on the exhaust cam and not bother swapping pins. Just for clarification, both gears should have pins, but the intake one is not really necessary.

As far as compression, shaving the head raises compression. Outside of a rebuild using different internals (which is the best way) a MLS gasket will work. What sort of internals are you running, or was the rebuild just stock + the 360 bearings you mentioned elsewhere?


This. Shaving the head raises compression which is opposite what you want.

If you did not get lower compression pistons which is the preferred route, an MLS will work.
-Nick
91 E30 M42 with VEMS