Tips for EL XR8 camshaft change (long)
The following might be useful to any of you who are looking to do a cam change on your Falcon. Mine is an EL series, but I’m sure most of this is common.
For what its worth, I chose, the 2031, which was developed in the USA specifically for the Cobra Mustangs, which had 1.7 ratio rockers as standard. After reading a reasonable amount about this cam, and finding out it was a reasonable $390 (compared to some other brands), I decided to go with it. I did not check PVC (piston-to-valve-clearance), as I had read many times that it was acceptable, even with larger valves. This might be an issue if you go with a different profile. I can’t describe how to do this step, as I didn’t do it !
If you didn’t already have valve springs, new ones would be required with this cam (and I’m sure most others, especially if you’ve a few km’s on the motor). I already had new springs, so this was not an issue for me. With roller cams, you are able to re-use the lifters, if they are in an acceptable condition. The crane specifications state that standard length pushrods would be acceptable, so the only other new item that I required (apart from intake, rocker cover and timing cover gaskets, and oil/filter) was a new timing chain set (about $80).
The timing chain set that I purchased was a rollmaster double roll 06b-2 chain, which had an indexible crank sprocket, giving the ability to advance or retard the cam by up to 4 degrees. Generally advancing the cam timing will move the power band lower in the rev range, while retarding it will move it higher. The following describes the process required to change the cam and timing chain.
Begin by removing the bumper bar, remembering to disconnect the cold air duct to the air box (if you’ve fitted an auxillary duct). Note that the XR indicators have one screw holding them in at the front, and a ‘push-in’ ball fitting at the rear. Remove all other bolts and screws before the 4 off main ones in the centre of the bumper bar. Next drain the coolant, and remove the radiator fans and radiator. Put engine at TDC # 1 cylinder. I did this by turning off the crankshaft pulley retaining bolts.
Remove the crane pulley and harmonic balancer. You will need some sort of puller for removal of the harmonic balancer. Begin by removing the (single) bolt in the centre of the crank. As this is very tight, you will need to prevent the engine from rotating as it is removed. I achieved this by screwing 2 off 2” x 3/8”BSW capscrews into 2 of the crank pulley retaining bolt holes. Then use these to put a steel bar through, and brace this against the turning force. You will probably need to spray some WD-40 on the crank bolt, and use a breaker bar and extension bar to loosen it. Once you have the centre bolt loose, do not fully remove it. You will want to leave it in place to push of with the puller, so that you do not damage the threads in the end of the crank.
Remove the upper and lower manifolds (I have already described this in another thread “Tips for installing explorer intake”, or something similar). Remove the rocker covers. Next you will need to remove all the valve gear (except valves and springs). Note that every item must be installed back in its original location and orientation, so label everything carefully. I already had Yella terra 1.7 roller rockers, and as the dual shaft design of the roller rockers meant that they could only go in one way, I simply wrote the cylinder number in marker on the rocker set, and placed them in a clean cardboard box. As I removed the pushrods I wrote the cylinder number, intake/exhaust and ‘top’ on them.
To remove the lifters you must remove the retainer ‘web’ that retains the 8 off lifter guides. I think this only goes on one way, but I marked ‘front’ on it anyway. The guides must go back in their original location and orientation. I wrote the cylinder number on the side of them that was in the middle of the motor. They are marked with ‘up’ on them, so you know which way they go otherwise. Before removing the lifters I put a single dot on each of them to indicate which way pointed to the centre of the motor. This was useful because a couple of times when lifting them out, they spun, which could cause some confusion as to which was way in the middle. I then wrote cylinder number and intake/exhaust on each one, again on the flats that faced the middle of the motor. This is important as they are meant to spin the rollers in the same direction as they originally did.
Next remove the timing chain cover and waterpump. Note that these can be removed together, saving you having to replace the gasket between the two. Just be careful to not undo the bolts with only hold the waterpump to the timing cover. Note that many of these bolts are common between the two, with the central ones generally being only waterpump ones. You can sort of tell by looking for bracing on the cover. There is also 4 off bolts in the timing cover from the oil pan, so don’t forget these. Before you remove this, it says in the repair manual to “cut the oil pan gasket level with the face of the engine block”. I did this, but really it served no purpose, as the oil pan gasket generally stayed stuck to the pan anyway. It will take a bit of removing, as there are 2 off dowels at the bottom of it, which I presume are there to help line up the crank-shaft oil seal. Once the timing cover is off, cover the hole created with a rag or something, so that you don’t get rubbish in the oil pan.
Remove the camshaft retainer bolt. It will be tight, so you will need to just slide the harmonic balancer on far enough to engage the key, and then use the 2 off cap screws again to hold the engine from rotating.
If the engine has a few km’s on it, the chain will have stretched, and thus the timing chain will slide off easily, just ensure you slide it off the crank and cam evenly. Next remove the cam retainer plate. I labeled how it is installed (even though it was a label stamped into it).
Unbolt the power-steering and transmission coolers from the front of the air-conditioner condenser. You do not need to disconnect the actual lines, they will swivel far enough. You will need to remove the air conditioner condenser out of the way to allow enough room to slide the cam out of the block. Fortunately you do not need to disconnect any of the A/C lines, saving you the cost of a re-gas. I was able to rotate it out of the way enough by removing the passenger headlight and undoing all the hard line clamps. A small amount of bending of the steelwork behind the headlight, and at the bumper bar main attachment point was needed, along with unbolting of the A/C and power-steering bracket from the block to allow enough movement. A bit of stuffing around, but worth it for the savings. Note that there are only 2 bolts at the base of the condenser, with the upper half having 2 rubber ‘pins’ to hold it in place.
Screw a 6” long x 3/8” BSW cap screw into the end of the cam. Gently slide the cam out of the block, taking care not to damage or dislodge the cam bearings. The long bolt allows you the leverage necessary to lift the cam once the cam comes out off the bearings, and the lobes hit the cam bearings.
With the cam and timing set out of the engine, put a little oil on the cam, and check that the sprocket slides on freely, on both the cam and crank. Put the dowel pin in the cam. Clean the rust preventative off, and then liberally cover the lobes and bearings with assembly lube.
Slide the cam gently in the block. Refit the cam retaining plate, and torque the bolts to 15 Nm. Put the timing chain on. If its an ‘indexible’ type, ensure that it is installed at the required setting. As the new chain set will be tighter, you will need to be real careful that the two sprockets are aligned as it is slid on. Rotate the cam as required to get the dowel pin to line up. Install the cam retaining bolt with some ‘Loctite’ and torque to 60Nm. You will need to partly refit the harmonic balancer to prevent engine turning.
Clean all the old gasket material off the block and timing cover. Refit, ensuring that the dowel pins are in place. Put a bit of silicone at the junction of the cover and pan/block. Torque bolts to 25Nm.
Put a liberal amount of assembly lube on the roller end of the lifters, oil the body, and refit the lifters in the original holes. Re-fit the guides and ‘web’ plate in original locations. Refit pushrods in correct orientation and locations. I was just able to re-use these and still have the rockers tightened to specification (25 ft/lbs after zero free-play, was around 3/8 of a turn).
Refit rocker covers. I used rubber rocker cover gaskets ($15)., which was much better than the cheap cork ones in some gasket kits. Refit the inlet manifold.
Refit the distributor. As the lobes on the cam will not be in exactly the same location relative to the distributor drive, rotate the engine over by hand and ensure that TDC #1 cylinder, is actually where the rotor is pointing. Remove the distributor and adjust as required.
Change the oil, and add the crane oil fortifier to the new (mineral based) oil before starting. Refill engine with coolant.
Start engine and run between 1500 and 2500 RPM for 30 minutes to break in the cam. Do not let the engine speed get lower than this, as there is insufficient oil pressure at lower engine speeds. Stop after a few minutes and check for leaks. Change the oil after about 100 km.
There was a slight lope to the idle with this cam, at least enough to let you know its not standard. Although a bit rough to start with, I did not need to adjust the idle speed. There was virtually no loss in low end torque, with noticeably more up higher in the rev range. I was able to run more ignition timing with this cam, and it was necessary, as without it, some power loss appeared to be evident. I advanced to 34 degrees with no sign of detonation. This was quite a bit of work (but not too difficult, just time consuming), best done over a full weekend, but worth it for the results.
I found that the fuel economy out on the highway was about the same, but around town was a bit worse, although nothing terrible. The cam change alone dropped quarter mile ET’s from 14.68 to 14.42, and increased MPH from 93 to 97.5.