I have a 312 standard bore and pistons, Mummert aluminum heads and his 270 cam. Sanderson headers, MSD ignition, currently running 3 94's on an Edelbrock 573 with a Fordomatic but have a new low riser Tbird 4bbl intake and Summit 4bbl ready also. Can I safely advance the cam timing to bring the torque lower in the RPM range? I installed the cam originally straight up using the standard index on the gears. Will this change flirt with piston/valve clearance?

57 Black Tbird 312/auto

There shouldn't be any danger. Did you degree the cam when you originally installed it? Do you have the adjustable timing set or are you going to use offset keys?


Lawrenceville, GA

I would be using an adjustable timing set if possible. I did degree the cam when I installed it but it was my first time using a degree wheel with the dial indicator was never real confident about the outcome. I was pushed for time getting the engine back together and in the car as I had to take a year away from it for medical stuff. Is it possible to accurately degree the cam with the heads installed? I used a Comp Cams degree wheel but I had to "finesse" the set up to the crankshaft. Is there a more Yblock compatible degree wheel and setup? The cam seems to "come in" about 4200rpm or higher and I wonder if I could lower the torque rpm range.

57 Black Tbird 312/auto

That cam should come in a lot sooner than that. It sounds like you have a tuning issue, carb, ignition timing, too tall a gear, something that is not the cam.



You can degree the cam with the heads installed. You'll need a piston stop. It threads into the plug hole. It should be pretty easy to find. It will probably be best to remove the rocker shaft for a more direct shot to the lifter. Extensions are available for dial indicators to reach all the way down to the lifter.

I don't believe there is a wheel with a bushing that will work for a Y-block. I had one made.

You will definitely want to degree it before you install the adjustable timing set so that you are sure of where it is before you change it.





Lawrenceville, GA

It may well have to do with the progressive linkage and the 94's. 3x2's are great and I love the look but as usual, they are hard to get right and stay right. The tachometer is the original stock cable drive and is unreliable. I have a new Sunpro to install after I finish this disc brake swap I am doing this weekend and then going to put the Mummert intake and Summit carb to see what is up. I could take the valley pan off then to do the cam degree. The Fordo probably doesn't help and I hold my breath each time I wind out the motor. The rear ratio is supposed to be a 3.10. I need to go through the ignition timing then also. Ran with no vacuum advance and high initial added to the mechanical and now have the vacuum advance hooked up. With Mummert heads Ted ballparked the compression ratio at 10:1 and I need to be careful with detonation using the crappy gas here in California. I would like to know where the cam is just to be sure I got it right the first time.

57 Black Tbird 312/auto

Look at the other things first. The cam timing a good bit of unnecessary work if something else is causing the problem. And I bet that something else is to blame.



I don't think there is enough room in the valley for a dial indicator but you can certainly check.


Lawrenceville, GA

Charlie, Better I stick the disc brake thing and quit thinking the cam timing. If it still is a question when I do the T5 conversion, I could do it when the motor is out for that. You're right about the dial indicator, I remember trying to set it up and it wouldn't fit correctly. It would a good thing if some company could make a degree wheel that could fit a Yblock. Cleaning up the firewall today and just touched the hood release cable end. !@#$% 55 year old cable broke and it fell on the floor. Ordered another. Thanks for the advice.

57 Black Tbird 312/auto

Assuming you have a symmetrical camshaft and your harmonic damper is reading TDC correctly, an estimate of where the camshaft is installed can be performed doing the following check.  Rotate the engine so that both the intake and exhaust rocker arms on either the #1 or the #6 cylinder are exactly level or parallel with each other on the overlap cycle.  The exhaust will be closing and the intake will be opening.  I use a small straight edge on the roller rocker arms.  Doing a straight edge check across the top of the valve spring retainers will also work for this.

Once the rocker arms are level with each other, then look at the damper and take notice of the number of degrees from TDC the damper zero mark is resting.  If the zero mark is before TDC, the cam is that number of degrees advanced.  If the zero mark is sitting after TDC, then the camshaft is that number of degrees retarded.  If the damper zero aligns with the timing pointer, then the camshaft is sitting straight up or zero degrees retarded or advanced.  While this is not exact, it is a quick check to see if the camshaft is in the neighborhood of where it belongs.

Lorena, Texas (South of Waco)

Mark, a degree wheel is pretty easy to make, use one of those drafters protractors and transfer the degrees to a sheet of plastic, aluminum,cardboard whatever, Use a large set of dividers to make the circle size you want, drill the correct hole pattern in the center and presto, you have a degree wheel.

55 Vicky & customline

58 Rack Dump, 55 F350 yard truck, 57 F100

59 & 61 P 400's, 58 F100 custom cab, 69 F100, 79 F150, 82 F600 ramp truck, 90 mustang conv 7 up, 94 Mustang, Should I continue?

Ted, thanks for explaining a way to check the cam timing. If that method comes up correct, I can probably quit thinking about it. I bought some timing tape to put on the damper to make timing a little more visible to these aged eyeballs. Making a degree wheel like Billy describes is on the list as well. Need to make something that will fit on the crank pulley or behind the dampener bolt and still allow a socket to fit over the bolt to turn the motor.

57 Black Tbird 312/auto