CAPS OFF.
"In this Special Series, during VANOS bulletproofing of my S54, we took a slight detour in internal performance upgrades: let's cam it!
On this entry, we fit one cam, and we wait [...] and wait [...]. I document the little things we did while in there including the notorious valve adjustments. "
-Matt
Out & about.
With the engine out, the process of getting to, and removing the OEM cams was a simple process.
I filmed and edited a reel as a trailer to this entry here.
I can't underline enough how planning these upgrades and services will save you a lot of headaches, and money! If you're planning a similar package to mine with cams, VANOS and bearings, it is worthwhile to consider pulling the engine.
We had already taken the VANOS system apart in the previous entry here which meant the cams were essentially a few bolts away.
The cam caps come off by removing nuts from the threaded studs.
Each cap has a specific position and is numbered.
Once the caps are off, the OEM cams come out.
We removed the rear camshaft gears as they will be re-used on the Schricks. These are used to make camshaft position with sensors located at the back of the S54's head.
You then gain access to the rockers, all 24x of them come out.
The OEM rockers were in pretty good shape for a 190,000km engine. There was little wear, showing the engine had been well maintained.
As we removed the OEM cams and placed them next to the OEM cams, little could be discerned from my untrained mind.
Can you make out the differences? The duration increase is barely noticeable.
Time for the main event.
With the OEM cams and rockers removed, we transferred over the rear cam gear and went to work starting with the new rocker arms.
We first started with installed the 24x new DLC coated rocker arms from Schrick. There is no specific order to them.
With the rockers positioned, the 280 exhaust cams went in without any issues, and got bolted them with the caps in their proper order.
You'll notice the outer studs are slightly longer than the inward studs. Some of these are use to install the valve cover.
Unplanned intermission.
We then had to stop, and stop we did for months. The first half of this entry took place during April, while the second half is current as this is published: July.
Here's the backstory to this unplanned intermission: I received 2x 280 exhaust cams earlier in the Winter.
Notice any differences yet? There aren't any from my unboxing entry.
I could have avoided this by confirming the SKUs were correct. AH! Trust but verify, we're at that stage.
We received another replacement camshaft that was in stock, only for it to be yet another exhaust cam. We ended up receiving the correct 288 intake cam later on but it was too late, the hiatus was on.
Unfortunately, it was Spring now - the shop was busy and the ship had sailed. We'd have to revisit this in the Summer's slowdown.
The S54 went back to its corner and the valve cover got put in temporarily.
Resume.
The main event resumed abruptly when I receive a picture from Phil showing off the installed cams with a smiley face. I'll be damned - hopped in the M3 V8 and dashed to the shop.
There it was - sitting by the garage door, we were seeing the light again. Both cams were in, it went in without hiccups - and I had a little surprise awaiting.
Valve adjustments.
Phil had already adjusted all 24x valves! He ran me through the process on a single valve to better understand what it entailed.
The S54 uses rocker arms instead of hydraulic lifters found on the newer S65 and S85 engines which do not require this. It auto adjusts using oil over the life of the engine.
On the S54, valve adjustments are required every 50,000 or so depending on your driving style due to the constant slamming of the valve causes it to recede into the head. Without adjustments, the tip of the valve stem eventually will contact the piece that actuates it: our previous cams.
The adjustments is done with shims located between the rocker arm and the valve spring.
The valve spring upper retainer has a section machined to insert the shims.
Here's a shim! Removing using a specific magnetic tool. Don't drop them into the engine, you'll hate yourself.
The valve adjustment is done by inserting a specific shim thickness s and measuring the distance below the rocker arm to achieve the target clearance.
The clearance is measured using the gauge set pictured below. The target intake and exhaust valve clearance is 0.25mm on the 288/280 Schrick cams.
While they do tend to be similar - don't be a robot, and do it right across all 24x valves. Once the measurements are validated, the rocker arms get locked into position afterwards using this metal clip that was re-used from the original set.
With all valves adjusted, we rechecked torque specs on all bolts.
While we were in there, we also swapped o-rings on a few difficult to reach areas of the S54 when mounted. This particular bolt by the back of the engine has a o-ring that tends to leak.
Up next: we get back to the VANOS.
We finalize its bulletproofing with Beisan parts, and flip the engine to service the infamous rod bearings.
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