Subject: M60B40 V8 Cam timing upgrade Author: rick540 : member since April, 2007 : 1785 posts Posted on: 2010-04-05 15:10:42

Attempt this upgrade entirely at your own risk.

Below is my own experience, yours may be totally different.

The cam setup in the M60B30/40 are fairly complex to set, and you need prior knowlege of how everything works as well as the ability to fabricate an acceptable degree wheel for this particular setup. (I printed one of the internet and glued it to cardboard backing)

To cut a very long story short, I just did quite a bit of research into camshaft timing, and the effects it can have. I then proceded to "experiment" with the 540, trying out different combinations of inlet Vs. Exhaust camshaft timing.

The M60B40 has fairly agressive cam timimg with quite long durations (valve opening times) and 28 degrees of overlap between the exhaust and inlet, and it is optimised for mid range power. The intake is fairly advanced and the exhaust retarded compared to the later M62B44 and M62B44TU engines. A lot of overlap improves midrange due to scavenging but reduces both idle quality and high rpm power.

I decided to sacrifice a bit of midrange for improved quality idle and low end torque and topend rev power by retarding the intake 14 (crank) degrees and advancing the exhaust 6 (crank degrees)

The result was really awsome , the midrange power dropped very little, the lumpy idle improved to perfection and it revs to the redline very willingly now, producing heaps more power from 4000rpm.

I still cannot beleive the improvement in behavior of the engine with the modified cam timing. This was the best thing I have ever done to this car. It is now much more refined. I think BMW were a litte over enthusiastic when they did this design, giving it too much overlap and emphasis on mid range power as opposed to driveability.

There is no question the low end and topend power improved significantly through this change, and interestingly the valve timing is now almost identical to the M62B44TU engine with a longer exhaust duration

M60B40 Standard timing

IO/IC 14 BTDC / 52 ABDC
EO/EC 48 BBDC / 14 ATDC

Inlet, Exhaust Overlap is 28.00 degrees

Intake Duration 246.00 degrees.

Exhaust Duration 242.00 degrees.

Inlet Cam Centerline 109.00 degrees ATDC.

Exhaust cam Centerline 107.00 degrees BTDC

___________________________________________________________

M60B40 modified cam timing

NOW IO/IC 0 BTDC / 66 ABDC
NOW EO/EC 54 BBDC / 8 ATDC

Inlet, Exhaust Overlap is 9.00 degrees

Intake Duration 246.00 degrees.

Exhaust Duration 242.00 degrees.

Inlet Cam Centerline 122.00 degrees ATDC.

Exhaust cam Centerline 113.00 degrees BTDC

1994 E34 540iA M60
1997 E39 540iA M62


Capetown South Africa
"The Mother City"

• M60B40 V8 Cam timing upgrade - rick540 2010-04-05 15:10:42 (1912 views)
  • Re: M60B40 V8 Cam timing upgrade - mi530i 2010-04-17 15:50:06 (712 views)
    • Re: M60B40 V8 Cam timing upgrade - rick540 2010-04-18 04:56:05 (498 views)
      • could you just be driving harder? (nt) - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-18 04:59:53 (388 views)
        • Re: could you just be driving harder? - rick540 2010-04-18 17:04:00 (410 views)
  • Re: M60B40 V8 Cam timing upgrade - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-05 23:27:41 (479 views)
  • Re: M60B40 V8 Cam timing upgrade - yaofeng 2010-04-05 20:31:13 (502 views)
  • Re: M60B40 V8 Cam timing upgrade - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-05 17:59:11 (666 views)
    • Re: M60B40 V8 Cam timing upgrade - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-05 18:07:49 (688 views)
      • Re: M60B40 V8 Cam timing upgrade - rick540 2010-04-06 00:27:44 (506 views)
        • according to bmw - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-06 05:53:00 (463 views)
          • Re: according to bmw - rick540 2010-04-06 06:19:34 (476 views)
            • have you got the specs of the m62 cam timing? (nt) - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-09 08:15:41 (752 views)
              • Here you go - rick540 2010-04-09 13:27:43 (477 views)
                • Re: Here you go - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-09 18:35:19 (437 views)
                  • I forgot to mention lift - rick540 2010-04-10 08:19:20 (478 views)
                    • Re: I forgot to mention lift - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-10 17:43:39 (406 views)
                      • i don't suppose you would - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-10 17:49:25 (424 views)
                        • Re: i don't suppose you would - rick540 2010-04-11 05:58:05 (432 views)
                          • only 30.mins work with a dti - explodingbudgie 94 e34 540,95 e31 840ci 2010-04-11 06:55:55 (411 views)
                            • I can, THANKS for the book tip!! (nt) - rv8flyboy 2010-04-20 17:36:38 (390 views)