I plan on taking my C heads in for freshening up. They have less than 75K on them. I planned on using block off plates for the cross over (if needed) I have a new Performer manifold I will be using. The 455 is re-done with 1970 internals and a Lunati Voodoo .224/232@50 .488/.510 with High Rev hyd.lifters. I am using the stock exhaust manifolds (W/Z) with 2 1/2" pipes and race pro mufflers.

I would like to keep it economical yet maximize performance on the machine work that will be done. For instance I want to mill the heads to make up for the Felpro gasket thickness that I will be using. I would like to know how much I can have the heads milled w/o needing the intake milled (taking into acc.the factory head gaskets vs Felpro). Also at what point would I have to change push rods. Any other economical recommendations you can make would be appreciated. Ebrock heads are not in the cards.

Thanks,
Randy

 

Keep in mind using the block offs will render the heat riser in op. This will make it a bear (at times) to warm up when cold. You can convert the carb to electric choke fairly painfully to solve this. I chose to install the iron blocks-offs into my intake verses the heads. It was simpler for me to weld the plugs into it verses the heads. Plus I figured Id rather sacrifice the intake rather than the C heads should something crack or if I ever wanted to go back OEM. I tweaked the divorced choke coil to work acceptably. So mines a bit cold blooded, preferably, but its not driven in the cold and I always let my engines come up to op temp for many reasons and to provide enough heat to actuate the lightly set choke pull off bi-metal coil. Dont forget to eliminate the stove flap in the drivers side exhaust manifold. I removed mine and welded the shaft holes shut. I realize your going with an Ebrock intake. Consider having it aluminum welded then milled. I prefer the welding method as the drop-ins tend to rattle after a while.
Its a great performance enhancement. Less restriction on the exhaust mani...Cooler running carb = denser fuel charge on hot days. My plight was to rid the car of the heat soak hot starts I couldn't rid. This mod along with the heat isolator carb base gasket solved it.

 

Some great tips, much appreciated. Hopefully someone will also chime in on the milling and push rod/ spring details as well.

Thanks,
Randy

 

If you're doing just to keep the intake a few degrees cooler then you're missing the boat.
The better reason to do that, along with welding up the center divider, is for better scavenging of the center four cyl when using headers. Otherwise they essentially share the same cavity, which is detrimental to good/equal ex pulses.