Now that was very interesting and informative ...

____________________________

Extremely interesting to say the least. Shouldn't there be a fool proof way for those of us that are using custom ground cams to check this? I'm not an expert on the art and science of cam grinding but since #6 in in sync with #1, I would think the valve/push rod movement should duplicate, at the same degrees, as #1?  My cam was ground by Oregon Cam, it's a clone of the stock cam used in 1957. I found the sweet spot is 4* advanced. It seems #1 is the cylinder we always use to dial in a cam. I never thought to back those readings up against a cylinder on the other bank - #6 in this instance. I have never seen anywhere any reference to where the lifter bore is at. Evidently all are not equal.  Good discovery. Any feedback would be very welcome. Thanks in advance, JEFF...................


64F100 57FAIRLANE500

The issue I have now is everything is removed, the Isky field method of determining which side of the fence the overlap falls on needs the balancer and pointer and TDC. I guess I could use a piston stop and mark the crank snout and block or something like that. Not a show stopper to determine TDC though awkward. The chain stretch did exceed limits of 0.5, the new timing set should arrive today.

You can print a degree wheel off the internet and print it on your computer.

  Dennis in Lititz PA

I don't have the capability to print at this time.

I understand now a little bit better the routine Ted mentioned. Determine TDC, and install a pointer. (I guess I could use an old pie plate tin or something for my wheel)

Then rotate engine so #1 valves are perfectly at overlap using a straightedge.

Then check to see what side of the TDC mark on the wheel the pointer falls. If a few degrees BTDC, it would mean the camshaft is advanced. Though crude, it would indicate whether the camshaft is advanced, or "straight up", or retarded.

Checking the original timing set chain using the deflection method outlined in the shop manual seems to show it within spec, though the slop in the chain with respect to rotor movement seems a little sketchy. Seems to allow for about 8° or maybe 9° before the slack is taken up.

OK, rigged up a disposable pie plate and a coat hanger for a pointer and determined TDC. With #1 valves at overlap, it looks to me like the camshaft falls well on the slightly retarded side of the fence, maybe ~ 4 degrees crankshaft or something like that. This translates to 2 camshaft degrees?

Seems to me timing chain stretch plays into this as well.

Late valve timing, any amount of chain stretch just makes things worse. My precision-engineered pie plate & coat hanger assembly should show the new crankshaft/camshaft relationship when a new timing set is installed or whether an offset key might be warranted.

Something I've read on different forums, for a street driver is to simply advance/retard the camshaft phasing as required to achieve the highest static or cranking compression. This an acceptable procedure? In this method would there be something like a definite peak observed that would be found at straight up, or +1 or +2 whatever, and then it would start to drop off?

The old worn timing set chain resulted in the cam timing roughly 2° to 4° retarded or near enough. Given a factory 1964 camshaft and 8-1 compression, what cam timing is optimum? +1, +2, +3 ? I'm not trying to make a hot rod, don't misunderstand, just a smooth running machine.

It seems a 2° advance would compensate for chain stretch. Ford detuned the Y block considerably by 1964 though, I don't believe camshafts and/or timing sets were ground for emissions (retarded phasing) until much later. Basically, I want to do this right, and do it once.

It seems a 2° advance would compensate for chain stretch.

The only way to compensate for chain stretch is replacement with a QUALITY TIMING SET.

Also consider if the block main saddle was ever trued, it may have raised the CL of the crank and therefore needs a specialty shortened chain.

____________________________

Besides the variables involved with manufacturing all the various components, timing chain elasticity and stretch is why you want to initially advance the camshaft.  Over time the chain will stretch which will ultimately retard the camshaft.  Worn gears also contribute to camshaft retard.  Six to eight degrees of camshaft timing retard is not unusual with a worn chain and gears.  New chains will exhibit elasticity and that’s where the chain ‘expands’ with rpm and also retards the camshaft.  This can be seen with a timing light with the vacuum advance disconnected and bringing the rpms up until total timing is achieved.  By going even higher on the rpms, the ignition timing can be seen to actually start retarding.  This is nothing to do with the distributor but instead is the timing chain stretching due to elasticity and further retarding the camshaft which in turn is retarding the ignition timing.  As the rpms come back down, the chain comes back to its original length and camshaft timing falls back to its original position.
 
Advancing the camshaft timing causes all the opening/closing cam events to happen earlier.  Of importance here is the intake closing event.  When advancing the camshaft, the intake valve closes earlier which gives more time for the piston to compress the fuel/air mixture.  This makes for a higher cranking compression number which in turn increases the low end torque of the engine.  There are limits for the amount of camshaft advance so it’s always best to go with the camshaft manufacturers recommendations in lieu of experimenting.
 
Always remember that when changing the camshaft timing, the valve to piston relationship also changes.  When advancing the camshaft, the intake valve gets closer to the piston while retarding the cam creates a scenario where the exhaust valve is closer to the pistons.  For our flat tappet camshafts, changing the camshaft timing 4° typically results in about a 0.025” change in those valve to piston relationships.  If valve to piston relationship is marginally on the close side, then changing the cam timing can force the need for additional depth on the appropriate valve pockets in which to compensate.
 
While four degrees of advance seems to be the industry standard for installing a street camshaft, altering this number can be beneficial in certain applications.  I did a Mopar 360 that was a four wheel drive farm truck and was informed that it would be used on very rough terrain with lots of gulleys.  That camshaft was installed with 8° of cam advance to make the engine more responsive in the very low rpm ranges where it would be driven the majority of the time.  That truck does exactly what it was built to do.

Lorena, Texas (South of Waco)

It sure seems that data for performance stuff is plentiful, though what about OEM stockers? Aftermarket cam grinders build advance into their products. Consequently they usually recommend installing their products "straight up". For us "as advertised" folks, it's a little harder to come by information. Some say a "small" cam doesn't benefit noticeably from advance, others with heavy cars and trucks sure seem to like it. Everyone agrees cam retardation has major problems in a street driven vehicle.

What did Ford do with the Y-block camshaft profile from the high point in '57 era all the way up till the '64 detuned version?

One advantage to stock or non-modified engine enthusiasts like me, it's much more difficult to assemble a selection of parts where stuff starts banging into each other. That is my hope anyway.

There would/should be "no danger" of valve/piston contact running a 4° cam advance, my thinking here is based simply on account of the fact there was no issue in that regard running 4° retarded? Or, maybe it's more complicated than that.

The Rollmaster set is about the only one with an adjustable crank gear for Y-blocks? No-one sells "just" the adjustable crank gear, natch. The Rollmaster timing set would allow for a maximum of 4° advance at the cam itself afaik. To add more camshaft advance would require a new offset key broach.

I'm surprised in a way the OEMs didn't maybe offer provision for an easier, more convenient adjustment method to cam timing, given how important it is.

One thing I noticed last year, was experimenting with valve lash. After tightening it up some below .018" to maybe .015" the manifold vacuum really dropped off. I assumed then a valve was hanging open. Now I'm not so sure, .015" shouldn't cause this - maybe it was more the result of an already excessively retarded camshaft timing? One thing I expect to see is improved engine manifold vacuum throughout its range at the initial (say, 6° BTC) factory settings. I'm not sure how jetting and carburetor calibration will be affected.