When you installed your cam did you do it straight up or did you degree it? If straight up, does the cam make good power and respond well? If you degreed it in was it very far out or on the money?
I degreed mine, needed a couple degrees from 0. It's not the cam that is inaccurate, there's a lot of slop in the tolerance for the crank keyway. If you're willing to pony up for a custom cam, seems only natural you'd pony up for the degree kit to do it right.
Helped a buddy degree his - it was 4 degrees off at 'dot to dot'. Whether custom or off the shelf - they should always be degreed unless you're willing to just guess at the cam timing.
Edit - just to clarify - it's not just a cam manufacture issue -- the cam gear pin location, crank gear key location, the 'dot' stamp on the gear(s), crank key location, and block alignment between cam bore, lifter bores, crank alignment all have a bearing on how accurate a 'dot to dot' installation actually is.
You can degree the cam with the heads on or off. As for your other question "What ford does the motor need to be in?" - it doesn't need to be in a Ford at all. Mine is in a Volvo, and it degree'd in just fine.
Ditto Stangfreak - many cams (customs) have assymetrical lobes, and finding the lobe centerline is extremely difficult; also, be sure to use a positive stop to find tdc - don't trust the timing pointer or use a dial indicator to simply ID when the piston seems to be at the top.
If your gonna spend the money to get a "Custom Grind Cam" then you should degree it and follow the spec's to every number....If your off a degree or 2 could cost you HP.
Red 5.0 - it's not that complex. Instead of setting the cam so that the intake centerline hits at a certain degree, you simply set the cam so that the intake is open .050" at whatever degree the cam card says that lift should occur at. For example, on the E303 cam, the cam card calls for the intake to be open .050" at 0 degrees TDC. So you use your dial indicator and degree wheel to measure, and then pick the slot on the indexed gear set such that at TDC, the intake is open to .050".
Sounds simple enough. So all I need is a dial indicator, degree wheel, and something to mark the degree wheel. How should I go about finding exact TDC?
Positive stop – obtain an old spark plug for the Ford engine – most of us have at least one laying around. Put it in your vice, and with tool of destruction you deem appropriate – cut off the ground tip and bust up the ceramic around the center electrode. Keep pounding to get the ceramic and center electrode removed so you’ve got a good ¾” or so of hollow space inside what used to be the ‘business’ end of the spark plug. If you happen to break the ceramic on the part that is exposed when the spark plug is installed, don’t worry about it. Once you’ve got a nice hollow space in the tip of the plug, take a 5/16” tap, and cut threads inside that end of the plug. I found that diameter to go right in without any drilling required. Once you’ve cut threads, insert a bolt about 1.5” to 2” long, and screw it into the threads you just cut. Then take your hack saw and cut the head off the bolt. Wouldn’t hurt to take your file and dress up the freshly cut surface so no sharp edges or shrapnel enter the combustion chamber. Also clean up the threads on the plug so that it easily screws into and out of the plug hole.
Determining TDC with head on – assumes new cam is in place with gear set 'dot to dot', all rockers are off. Place socket/wrench on the harmonic balancer bolt and rotate engine so that the piston will be slightly down in the bore. Unscrew the spark plug in that cylinder, and replace it with the positive stop you just made. Only screw the positive stop in hand tight – be sure your bolt isn't too long, you don’t want to jam it into the cylinder wall on the opposite side. Install your cam degree wheel and pointer. You may want to remove all spark plugs at this point because it will make it easier to smoothly turn the engine over in small increments. GENTLY rotate the engine clockwise until the piston comes to rest against the stop. Note the degree wheel reading. GENTLY rotate the engine in the opposite direction until the piston comes to rest against the stop again. Note the degree wheel reading. TDC is exactly half way between these readings. Calculate where that position is on the degree wheel, remove the piston stop from the cylinder, and rotate the engine to TDC as you calculated it. Make note of the reading as this is the base from which you will take all your readings.
Now simply set up your dial indicator on the number 1 intake lifter or pushrod, and see where (crankshaft degrees relative to TDC) .050" lift actually occurs. For example, if the cam card says .050" lift should happen at 5 degrees BTDC, and your measurements indicate that it's occurring at 7 degrees BTDC installed dot to dot, then you're 2 degrees off - in the advanced direction (the intake is opening 2 degrees earlier than the cam card says it should). So you'll have to retard the cam by 2 degrees to move it from 7 to 5. You'd pull the gearset off, and re-install using the "2R" slot, and then re-measure to be certain you've hit .050" lift at 5 degrees BTDC as the cam card calls for.
Zacly.... the @ .050 ( from max lift and after max lift) is the way to do BOTH.. it will tell you the Open and close degrees and then you add both of those numbers and divide by 2 and that is the centerline !! Or you can read .050 off the seat, add 180, and that will give you the duration!! Did you buy the cam used??? just a thought cause you said " no Paper work" ??
Thumper (mike!) - some custom cams, and more cams in general, are showing up with assymetrical lobes - that is, the ramp/lobe shape is different on opening than on closing. If that's the case, then your method of calculating the centerline won't work. That's the reason degreeing one based on the opening .050" lift degree point is preferred - it totally does away with any need to worry/wonder/figure out exactly where lobe center is. In any event, if the .050" opening point is set where it's supposed to be, the centerline will end up where it's supposed to be too.
Mike right on... the opening .050 lift is the way we used to do it in the 60's and 70's. then the Center line method became the choice as it is easyer to figure. and also your right on the center line after the base .050 is done. I really havent noticed any lobe profiles being so different at .050 before and after max lift to NOT show the centerline?? The next custom grind I set up I will ( for my info) check both ways!! and compare the numbers. I do know there are a few circle track cams and the old Superstock and pure stock cams that the lobes were radical so they would pass tech ( at the lift the inspection was) and make un-real HP and torque... those cams you had to check at the specs on the cam card... but the .050 before and after max lift still found the center line !! ??? HHHhhhmmmmmmmmmmmmmmmm.................
Just me.....................
Thumper
PS... hey NeQX... so your in at 0* at TDC?? or does that mean your in at dot to dot ( no advance or retard from the grind??)?? Or does that mean your ICL is 0* ?? I cant see how that helps with out the full tech and what you mean.. But it looks like your Stock with a FTI cam and are making 308 at the rear wheels... or is there Heads, Induction, gears, fuel...?? But then again I think Buddy said they can make over 400 HP on a 125CC stock head with his cams???HHmmmmmmmm..................
NeQX - not sure what you're trying to say; elaborate a bit. What does "0* TDC " mean? All that anyone is saying in this thread is that if you didn't degree the cam on install, then you've just hoped and guessed that the dot to dot install is gonna put the cam timing where it's supposed to be. And as often as not, the dot to dot install results in the timing being anywhere from 2 to 6 degrees off.