new 3/18/02, updated 4/01/02,updated 3/27/2004
Instructions per Doug Lewis' e-mail to me:
"Have them use very high heat when welding and only weld a 1/4" spot at a time. Put three spots on all 4 cams one at a time (i.e., weld on cam, then the next, then the next. Rotate the engine a third of the way around and repeat. Do this three times so that you've got three spot welds equally spaced around the cam and done with enough time in between as to let the cams cool. Too much heat on one cam will twist it out of shape). "
FYI - Doug recommends TIG or MIG welding and uses MIG, purely because that's what he has... I had mine TIG welded per these instructions and had the welds break (on an already very loose sprocket, responsible for major "ticking" in the engine) after only 50 miles! I do believe that a tight sprocket will be PERMANENTLY affixed by spot welds. Anyway, the offending sprocket has now been affixed with a complete bead around both sides and better not come off!
Got the car back today and am looking forward to many more enjoyable miles. It's really nice to enjoy the V8 SHO after the Focus loaner...
96 ES w/heavily welded mthafgn sprockets
I looked up on the web page to see what is all involved in welding the cam. I am at a loss. I talked to my brother-in-law and asked him if he could weld it for me. I would like to know about the cam and the tube. At this time I cannot get the funds to driver to GA to get them done. If he can do this I said I would let the list know. He has been a mechanic for over 14 years. He also wants to know what it takes to do this. Please let me know. Is the tube hollow? How many cams have to be welded? Help on this would be very much appreciated.
Doug is not a prick, he understands not everyone will drive to GA to get the
job done. Doug did a article about this for SHO CLUB last issue but if you call
him at 770-949-7191 & I think he will give you (or your B-I-L) ample details
to either do it yourselves or conclude you don't want to try.
Performance Plus is in Madison, Wi. (608) 277 8161 might also be a good place to call. They also specialize in working on SHOs.
I do know this, Doug makes (3) 1/2" long welds on each sprocket. The cam tubes are hollow and a lot of car must be made to not to warp the tubes. There are no cam bearings. A plain steel tube turn on the aluminum head cutouts. Cam bearing clearance is only .0008-.0024" so if you put a bend in the tube you can seize a cam real fast.
It take a very good welder to do the job, Doug uses a MIG welder but I am told a TIG weld would be preferred. You must also take extra care that no small bead goes down an intake runner or splatters any wear surface.
The cam tubes are hollow and a lot of car must be made to not to warp the tubes
Tim, the tubes are not hollow directly under the slave sprocket area. The
primary sprocket mount (though not utilized on two of the four cams is none the
less still there) is pressed into the tube and extends about an inch past where
the slave sprocket is mounted. You can verify this by inserting a rod at least
18" long into the hollow end.
As Tim, said, the process is fairly simple. One big note to add though. On
one of the cams on the front head (exhaust cam I think), the sprocket is
shielded on one side by something, and the other side by a six sided nut that is
used to turn things during some repairs. What Doug at FPS does is first weld the
cam to the nut, then weld the nut to the shaft.
The shaft is fairly thick metal, kind of like a cast water pipe, NOT like a copper pipe. The procedure is to put an approx 1/2" weld on the area visible on all four cams. Turn the motor with the key (bump it) and then do four more welds. Do this one more time. Not super important that they be exactly 1/3 of the way around, the diameter and amount of metal isn't going to take things out of balance, close is good enough.
Doug does not clean the cams of oil, depending on the heat of the welding process to clear the way. Not being a welder, I would guess this is OK.
Cover the entire area with cloths, I would soak them in water and wring them out to prevent fires. Carefully wipe up the area around the welded portion since you can't get rags in there very easy. I would do an oil change within a few miles of doing the procedure, just to be safe.
You can re-use all the gaskets if they are not damaged.
Remember you are bolting into aluminum, so go easy when tightening things up!