Hey guys, like the title says, I've got a couple questions about milling heads. ....whether it be AFR, Brodix IK's, Etecs, whatever, most have "about" a 64cc chamber.

Right now I've got a stock F body L98 shortblock, but eventually I'd like to step up to a flat top piston/zz4 shortblock. They were 10:1 CR with 58cc 113/zz4 heads. ....is it as simple as droppin 'em off at the machinist and saying that you want a 58 cc chamber? Do I need to CC the chamber FIRST, and confirm what they are, then figure out the thousandths to have milled?

I don't wanna have a 64cc alum. head chamber with 9.3 to 1 CR, but I don't wanna hack up $1000+ dollars worth of new aluminum either.

Combo is gonna be a 350 with a heavily ported TPI, a relatively smaller head (180 ish) and a hotcam or similar. Still researching of course.

 

Most head companies tells you the conversion factor. Most are .006" flat mill = 1 cc.

Brodix says this for the IK heads...
• Angle Milling:
.0078 in per cc
• Flat Milling:
.0060 in per cc

What buy a zz4 shortblock? You already have a roller cam 350 block. Just build yours.

 

OK cool. I'll just check with whoever I buy the heads from. My plan was to aim for about 10:1 with flat tops, and since my pistons are the stock dished, It'll probably be a touch lower, but i'm not worried too much.

....Hard to go wrong with a GM/factory built shortblock like the zz4, but yeah, you're right, I could certainly build mine cheaper. I just have to trust the shop that I end up choosing, which sometimes is easier said than done.

 

That be ideal to be exact but not necessary. Just verify your intake port alignment before and after milling. Make sure you can seal the china wall and dont have big gaps

And 9.3 to 1 aluminum motor can still run well. Just run a warm thermostat. 200-220 deg to keep heat in there

 

Yeah, I've been reading up on lower compression alum head motors. I'll probably aim for compression with my "eventual" flat tops, and just run a few points lower for now with my current dished L98s.

 

Building the short block yourself is not very hard. You should look into that, atleast read up on it.

Have block machined (bored, honed, hot tank cleaned, etc) buy all new crank, rods, pistons, etc. Measure your parts and clearances and put it together. Most name brand companies are very close if not spot on with finish machining so that should not be much of a prob.

Scat crank and rods, speed pro/sealed power/KB/ Wisco, etc pistons