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

Now that was very interesting and informative ...

____________________________

I was told that I was the first to bring up the issue, and yes, the owner of this company is now aware, and is also reworking two more camshafts that they custom ground for me earlier this year.  That makes three custom camshafts that he will personally make sure gets done correctly.  Can't ask for better customer service than that.  The listings in Howards Cams, Comp Cams, and several others is wrong, and unless someone goes to the trouble of degreeing all the lobes as Ted and I just did, they will never know that the camshafts are actually ground wrong.  Straight up is ok, but anything else will be off bank to bank.  Joe-JDC


JDC

Interesting.  I know it will probably fall on def ears, but did you tell those companies that they are doing it wrong?  If they don't know, they can't fix it.


Lawrenceville, GA

Camshaft phasing as you call it can create problems with aftermarket camshafts.  Ted and I recently found out that there is a problem with the industry standard for grinding camshafts for the Y Block Ford engine in that they are using the wrong lifter angle from bank to bank when custom grinding a camshaft.  If you use a camshaft from any company other than Isky, then they are using the industry manuals that list the degree for the Y Block, and it is wrong.  If you install the camshafts straight up, then the engine will run fine, but if you advance or retard the camshaft, then you run into problems (think phasing) with the bank angle causing one bank to be several degrees wrong, and will not perform as expected.  Last year I had a custom Comp Cam given to me for the EMC engine as a sponsorship, but we could not use the cam due to trying to advance it as suggested.  The lobes were all over the place in the 2* and 4* advanced position, causing us to go back to the Isky.  I recently had this confirmed when another brand of camshaft was custom ground for our EMC entry for this year, and straight up, it was Ok, but when we went to advance it, one bank was retarded, and the other was advanced, making it unusable.  I sent the camshaft back, and it was put on the Cam Doctor machine and confirmed that it had been ground wrong according to the industry standard information.  After obtaining the correct specifications for lifter bore angles, the camshaft has been reground and parkerized, and in on its way back to us for dyno testing.  Anything other than stock Ford or Iskendarian camshafts should be degreed if you are serious about performance gains without valve to piston, valve to cylinder wall, interference issues or degraded performance.  I am sure Ted will have enough material for a magazine article after we get through with this EMC dyno session dealing with double checking your performance camshaft installation.  Joe-JDC


JDC

That's a good point, altitude particularly plays a big role. Someone who lives in Denver won't see 20", and it would be interesting to know the best an engine in Leadville could pull.

Can't recall what ignition timing setting I found achieves good manifold vacuum but I'm pretty sure it exceeds 12°, it shouldn't be required to advance the timing much beyond this to get in the zone? See where I'm goin' with that?

Engine starts reasonably well cold though I think not as snappy as it should. Could be way off base on this chain stretch, it shouldn't hurt anything.

The manual shows the 12 pins and dits oriented on the fuel pump side. I takenit this is with #1 at overlap and #6 at TDC?

Tedster [and others],

" I can get a nice steady 18" to 20" Hg. and smooth idle..."

We should all remember that gauge-measured vacuum will also generally vary depending on altitude (will show less with higher altitude); and, specifically can vary from time-to-time (hours, days, weeks, season) due to changing atmospheric pressure/weather/temperature/season: Our Atm. Press. ["Hg] here at my home, 1,200' Above Mean Sea Level, has varied from lows of 27" to highs of 31"; and, summer temps can be +100*F or more (rare) with winter down to -45*F or more (also rare) - this will affect "vacuum" readings similarly; so, if you keep records, also note the atmospheric pressure and other conditions at the time you take your reading - for comparison.  Just another little "tidbit" to keep in mind.

Regards, JLB

55 Ford Crown Victoria Steel Top

In your article on camshaft degreeing I think you mentioned the relationship between #1 and #6 cylinders, I took it to mean that when #1 piston is at TDC compression, if the #6 valves are at overlap the camshaft and timing set is installed "straight up". It isn't that simple?

I'm a little unclear on this straightedge business, remember ya hafta dumb it down for us dummies. What do think of the Isky method using feeler gauges? If I can get this centerline business decidedly on the advanced side a little that would probably work for me and my OCD.

Yeah no like I said I didn't want to get tooinvolved. Too late for that, ha ha! It looks to me that there is 8° or 9° of stretch in this example, by carefull turning crank and observing rotor movement. Forgetting any potential stackup errors for the moment, that seems like a lot to retard to the cam? So I was looking to see that the centerline is at least on the "advanced" side of the crankshaft.

Does camshaft phasing affect cylinder compression testing? This engine measures 145-150 pounds cold across all cylinders, burns no oil, doesn't smoke etc. Heck it doesn't even leak, much. I see from reading forums some people advocate advancing or retarding a cam for best compression. This sounded promising to me, but I don't think it works that way. Is there a definite peak that is found as the cam phasing advances, and then it starts to fall off?

I assume, maybe wrongly, that engine manifold vacuum specifications listed in the manual are to be observed at factory idle ignition timing. In this instance say, 6° BTDC. TDC has been verified. I can get a nice steady 18" to 20" Hg. and smooth idle, but only by advancing the distributor timing by quite a lot. This has had me puzzled a bit, which isn't difficult. So that and other symptoms kind of led me to chain stretch. It kind of fits. I've played around with the mechanical advance and springs and such and it just seems to be a little anemic. When I replaced a fuel pump I noticed the chain looked old and was awfully loosey goosey on the slack side. I've heard the Cloyes sets are supplied with tighter tolerances, and the imported el-cheapos are to be avoided, but that's not news.

You degree in the camshafts due to machining variances in the various parts.  Stack ups are your enemy as that's when all the variances align with all being positive or all being negative.  In many instances those stack ups cancel each other out but like playing the lottery, sometimes you have a winner.  In this case, you have a loser.  I've found several engines now (all makes and brands) with the cam timing off as much as 18 degrees.  They all crank and run.  Some have detonation issues from being too far advanced while others are just sluggish due to being too far retarded.  As a general rule, it takes about a four degree change to be noticeable in the seat of the pants.  On the dyno, I can pick up differences with two degrees of change.  If the camshaft has symmetrical lobes, then measuring the lifter rise off of the base circle of the camshaft at overlap can give a good idea of advance or retard at TDC,   When being installed 'straight up', the exhaust and intake lifters will be the same distance off of the base circle of the camshaft.  This is an easy check on an assembled engine as a straight edge can be put across both the intake and exhaust valve retainers or roller rocker arms and when they are both level with each other, then look at the damper and see how many degrees from TDC you are at.  This is not as exact as doing the degree wheel method but it is close enough when looking for some serious discrepancies.  If the camshaft is simply being installed with the link count or alignment of the timing marks, that is not necessarily being installed straight up.  In those instances, the camshaft is simply installed and you do not know exactly where the lobes are in relation to TDC.

Lorena, Texas (South of Waco)