Thread: wiped lobes, new cam

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I've posted this tutorial many, many times to help prevent exactly what has happened here. Fellows, flat tappet cams are technology from the last century that has been relegated to use only as a concourse rebuild, where everything must remain stock in the motor, or in racing venues that require a flat tappet cam. Anyone building a street motor for their hot rod these days simply cannot afford to putz around with flat tappets.
http://www.crankshaftcoalition.com/w...ips_and_tricks

Riley, you said you liked the characteristics of the motor with the Comp cam, so don't change to different characteristics on the cam that you will use next. You've already told us that the brakes are soft, so don't use more cam than you have now. Use the same or very close to the same cam timing with a retro-fit Howards CL250705-10 hydraulic roller cam and lifter kit....
Howards Cams CL250705-10 - Free Shipping on Orders Over $99 at Summit Racing
Advertised duration 272/278
0.050" duration 219/225
Valve lift 0.525"/0.525"
Intake centerline 106
Exhaust centerline 114
Lobe separation angle 110
Use Howards 98611-K312 spring, retainer and lock kit together with adjustable pushrods to set the preload.
Crower Adjustable Pushrods 70000-16 - Free Shipping on Orders Over $99 at Summit Racing
Or you could pop for adjustable rocker arms, but they're pretty pricey.

Here's preload explained by a contributor on another forum....
Preload = compressing the lifter plunger slightly to make up for wear and most importantly, take up the slack as the cam and lifter are racing DOWN the closing ramp. The cam literally pulls the "floor" out from under the lifter and as the valve spring is trying to follow, the preload allows the plunger to extend and take up the slack.

Remove all spark plugs to make the motor easy to turn over.....
Standing at the front of the motor, looking toward the rear of the motor, #1 cylinder will be on your left, the first one, just behind the radiator. The next one to the rear will be #2, then #3, then #4 will be the last one on the passenger's side, next to the firewall. Looking on the other side of the motor, the driver's side, the front cylinder will be #5, the next one to the rear will be #6, then #7, then #8 all the way to the rear against the firewall. Do whatever you have to do to get this all fixed in your mind. You can write the order on the fender wells or make a diagram on a large piece of paper and sit it against the carburetor. Knowing which cylinder is which cannot be over-stated.

Also, knowing which way the crankshaft turns (Clockwise as you face the engine from standing in front of it, looking towards the rear of the engine/vehicle) and which way the distributor rotor turns (Counter-Clockwise) cannot be over-stated. As you are standing at the water pump, the crankshaft turns clockwise, the same way the hands on an analog watch or clock turn. If you were to climb up on top of the motor from the front and look directly down on the distributor with the cap off, you would see the rotor turning clockwise also. See the animation here.....
Ford 352 360 390 406 427 428 V8 Engine Specs | Torque Specs - Cylinder Numbering - Firing Order - Distributor Rotation

Finding TDC on the compression stroke of cylinder #1..... With a socket, extension and a long ratchet attached to the bolt head that holds the harmonic damper onto the front of the crankshaft, turn the crank clockwise while you (or a friend) holds his thumb over the #1 spark plug hole. Using the starter for this operation WILL NOT WORK, it spins the crank too fast. When your friend feels air pressure beginning to build under his thumb, that means that both valves are closed and the piston is coming up on the compression stroke of #1 cylinder. Watch the harmonic damper and you will see the notch that is cut into the outer ring of the damper come up to the Zero or TDC line of the timing tab. The distributor rotor will also be coming up to terminal #1 of the distributor cap. When that notch is at TDC at the crank pulley, STOP. You are now at approximately top dead center on #1 cylinder. It doesn't have to be EXACTLY at top dead center to adjust the valves.

Make a mark on the harmonic damper ring so that you can reference this TDC position again later. Either use a yellow crayon like they use at the tire store or a piece of tape placed at that position or whatever your mind can come up with. Make the mark at the top of the harmonic damper inertia ring. We are going to refer to this position as NORTH, because if you got down on your knees and looked at the harmonic damper from straight on, like you were looking straight through the centerline of the crank, this would be the NORTH position.

Loosen both adjusting nuts on both adjustable pushrods on #1 cylinder until the rockers are loose on the rocker shaft. Have your friend hold his finger on the tip of one of the rocker arms so that he is pinching the rocker arm down onto the tip of the valve, holding it tightly. Now, you grasp the pushrod for the rocker he is holding down and jiggle the pushrod up and down while using two open end wrenches to slowly tighten down the adjusting nut until all the slack is removed and you cannot move the pushrod up or down any longer. Be delicate here. This is not a strong-armed operation. You are simply taking all the slack out of the pushrod. Now, make 1/2 turn more on the adjusting nut.....1/2 turn.....180 degrees......OK, that valve is done. Now, move over to the other valve on #1 cylinder and repeat the operation.

You may have heard that you can rotate the pushrod with your thumb and forefinger until the pushrod gets tight and use that for adjusting the valves. While that may work for someone who builds motors day in and day out for a living, it may not work for someone who has no way of knowing how much resistance they should be feeling. Jiggling the pushrod up and down is BULLETPROOF and can be done successfully by even a first-time builder.

Now, you have both valves adjusted on #1 cylinder. With the socket and ratchet on the harmonic damper retaining bolt head at the crank, turn the crankshaft 1/4 turn clockwise. That will mean that the mark you made on the damper ring will move clockwise from NORTH to EAST.....STOP. Make another mark on the damper ring at the straight-up position. Now, you will have a mark at EAST and a mark at NORTH.

You have moved the crank 90 degrees and into the next cylinder's firing range. There are 720 degrees in a full cycle to fire all 8 cylinders, so turning the crank 90 degrees at a time will allow us to adjust the valves on all 8 cylinders with just 2 full turns of the crank. If you knew that an FE Ford's firing order is 1-5-4-2-6-3-7-8, then you would know that it is #5's turn to fire. Go to #5 and loosen both adjusting nuts, just like you did on #1. Have your buddy hold the rocker down against the valve stem while you jiggle the pushrod up and down to remove all play, all the while slowly turning the adjusting nut on the adjustable pushrod to remove the play. When all the play is removed, tighten the nut another 1/2 turn. Move on to the other valve on #5 and do the same.

Now, you have adjusted the valves on cylinders 1 and 5. Put the socket on the crank nut and turn the crank 1/4 turn to the right (clockwise, just like before). Place a mark at the top of the inertia ring like you did last time. This mark will be at NORTH. The mark you had at EAST will move to SOUTH and the one you had at NORTH will move to EAST. Following the firing order, we will now go to cylinder #4 and adjust both valves. Then we will move the crank 1/4 turn and make another mark and do cylinder #2. Then we will move another 1/4 turn (the crank has marks for each 1/4 turn now) and do cylinder #6. Then we will move the crank another 1/4 turn and do cylinder #3. Then we will move the crank another 1/4 turn and do cylinder #7. Then we will turn the crank another 1/4 turn and do cylinder #8.
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If preload is too much, the valves wont close.
If preload is too little, you will have lash at the valve, which causes noise, wear, and most importantly causes the little hyd lifter assembly clip to bear the pressure of the lifter plunger as it extends to take up the slop, not the pushrod taking the pressure as it should.

You didn't take my advice last time concerning the torque converter, perhaps you will this time......Use a 10", 2500 stall converter with the Howards cam that I recommended here..

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