We just picked up a 2005 MCS with the dealer installed JCW kit, including the diff from the original owner. Car wasn't running properly but otherwise is in nice shape with everything else working properly. Has about 120000 miles on it. I did a compression check and 1,3 &4 are all at 130 psi which strikes me as a bit low, but the car has not been driven in quite some time. Cylinder 2 has zero compression. A quick look with a cheap bore camera doesn't show any obvious piston top issue.

Are there any common issues with hole number 2 or that cause one cylinder to drop and the others are fine? Or valve issues that might be found by just pulling cam cover? No signs of coolant in oil or coolant loss reported by the previous owner, he said it rather suddenly started running poorly. Ideas and experience of other is appreciated.

 

Potential burnt valve. Leak down test should be your next task.

 

I only change the exhaust valve on them and they are back on the road again

 

Well tonight I got around to the leak down test, as Black Forest suggested. And a nice breeze flowed out the tail pipe. Which would tend to confirm perhaps the same issue as Tuercas noted with his cars.

So to those with vastly more experience with these critters, should I pull motor and go thru everything, or is the bottom end stout enough to not worry about at 120k miles, and just pull the head, maybe doing timing chain and tensioner while I'm at it???

 

I would pull the head as the bottom ends are fairly solid. Not a tough job to pull the head and would also replace the head bolts with a set of ARP’s. Hope this helps.

 

Thanks for the replies. I planned to do the ARP head stud set at some point. Guess now is the time. As it turns out clutch is original at 12ok miles, I'm going to pull motor and do that while tending to head. Good excuse to learn the ins 7 outs of taking one of these cars apart!

 

Doing that job you will most definitely. Get ready to replace lots of gaskets/o rings, rear main, input shaft seal and may as well service the supercharger. Will be nice and fresh after.

 

I just went through this in June when a bearing spun on Cylinder #2 also (most common cylinder from my knowledge). When I rebuilt mine I did the following and am extremely happy.

Wiseco pistons, k1 tech rods, king rod bearings, OEM main bearings and ARP cam, rod and head bolts. I already had a very aggressive cam and BVHead. I also had the crank balanced and of course the block gone through.

Food for thought while the motor is out the Valeo clutch and Wavetrac LSD.

Best of luck in the build and please feel free to ask me anything.

 

Joshua, Thanks for the input. going to a single mass flywheel and clutch is on my to-do list. Any thoughts on valves as it appears from the leak down test exhaust side in #2 has a problem. ARP head fasteners were on my list as well and for bottom end if I drive in there. Car already has the Quaife diff in it. What special tools are really necessary for this critter? And which just make the process easier and are truly nice to have?

Curious, are there know rod issues that prompted the K1 rods, or just going for more power and playing it safe when running it hard?

Cheers,

Ken

 

Ken

I used the K1 rods because I am planning on keeping the car forever, and the minimal cost increase was worth it. I still have my original block that I am thinking of building back to stock configuration as I have all the pieces. As for valves...its Supertech. They are the only brand to really put out a kit for the W011 . Motor.

Josh