Thread: My 460

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D1VE is a block casting number. Please post the head casting number. It is about halfway back on the side of the head just above the exhaust manifold mounting surface.

The cam specs are very mild for a BBF, I thought maybe you had over-cammed the motor, but that doesn't appear to be the case unless the motor is very low static compression ratio. You need at least 8.75:1 SCR to successfully use the cam that you have in the motor now. I'm now leaning toward the use of an '72-up emissions timing set as being at least one of the culprits. Do you have the receipt for the timing set that shows the part number and source of the part? If not, are you prepared to change the timing set to a part that is more inclined to work for you? If you are not prepared to change the timing set, are you prepared to set up a degree wheel on the harmonic damper and a dial indicator on the #1 cylinder intake and exhaust valve retainers and check cam timing? Checking cam timing would also involve using a piston stop to find TDC. Are you willing to do that?

Here is an example of a timing set that I would have spec'd for you in the first place. You'll note that it is for a '68-'71 motor....I'm not saying that I would have used only this specific timing set, I'm saying that I would have used one that is spec'd for the early motor because there would be no retard of the cam timing. This set will be zero or neutral when installed on the dots, neither advanced nor retarded.
http://www.jegs.com/i/Cloyes/220/C3037/10002/-1

What I'm getting at is that the install spec for the Comp cam is 107 degree intake centerline. That means that the intake valve is at its full open position (halfway through its open/close cycle) at 107 degrees after top dead center. I'm betting that the shop used an emissions timing set that has the intake valve fully open at something like 112-114 degrees after top dead center. This would extend the intake closing point and contribute to lazy low rpm performance. If the shop didn't degree the camshaft upon installation, then you have no idea where it is installed at.

So, there are your options.
1. Live with it.
2. Tear into the front of the motor and install an early timing set or advance the camshaft timing with an offset camshaft sprocket dowel or offset key. (not guaranteed to fix the problem, but my best guess).
3. Use a piston stop tool, degree wheel and dial indicator to find the valve timing as installed by the shop, then take appropriate steps to fix the problem by either exchanging the timing set or properly degreeing the camshaft with offset camshaft sprocket dowel or offset key.

CompCams says this is the largest cam they will recommend if using a stock torque converter. Going one step looser on the converter (for instance, a 2000 stall) will bring the rpm's up a little from a standing start and get the motor up on the cam a little sooner, contributing to better performance. You don't want to use too much converter though, if you are towing with the truck. You don't want the converter slipping excessively in the cruising range of rpm's. That would contribute to excessive heat which could shorten transmission and converter life appreciably. A good transmission cooler will help.

You'll want to change the ignition timing curve as well. When you use more cam, you need more initial ignition timing at the crank while keeping the total initial and centrifugal timing at about the same point as called for stock. You'll want to dial in....maybe 16 degrees at the crank, with the remainder of centrifugal timing shortened to equal the same total as the motor wanted before you dialed in more at the crank. There are kits available from any speed shop to accomplish this.

Some of the problem we are facing is not knowing the static compression ratio and how much ignition lead we can use before we encounter detonation on the available fuel.

I would finish off the motor with a good set of long-tube headers using an X or H pipe right after the collectors and a 2 3/4" exhaust system through mufflers of my choice. I'd change intake manifolds to either an Edelbrock RPM or a Weiand Stealth. In my opinion, either one will be worth 40 hp over what you're using. Top off the carburetor with a 14" X 4" air filter. Can't find a 4" filter? Glue two 2" ones together.

techinspector1, Do you think if I were to just change the torque convertor recheck,reset the timming and install an accel distributor (that I could take out of my cleveland)that I would notice any difference at all? As you know,Ford parts are not cheap,just the thought of replacing new and expensive parts is tough. In your opinion would a 2000 stall convertor and a distributor with some curve at least help somewhat?

Thanks,you are appreciated
eht