4-V Heads vs. 2-V Heads

I recently installed 2-v heads on my 72 and a Weiand single plane intake, new hydraulic cam and lifters. What a difference in power! Both bottom and top end. I would recommend this to anyone!!!!!!!!!! Go for it.

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Originally posted by tmoug:
My question is I am getting ready to build my motor in my 74 Pantera. I have a set of 4-V quenched heads that I was going to install. However, I hesitate becuase so many people are talking about the 2-V Aussie Heads. Is there really a difference in performance between the two? If so, what kind of difference? I've heard the Aussie heads have a much better bottom end but runs out of power before 6000rpm? I have also heard the 4-V quenched does not lose any bottom power and pulls up to 7000rpm. I am looking for my motor to pull very strong to between 6000 and 6500 rpm but not lose much bottom end power. Any input would be welcomed. In addition, any thoughts on intake single or dual plane?

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Keep in mind that the "small" 2V valves & ports are, as-stock, larger than the largest ported 350 Chev valves & ports ever built. 4V valves & ports are big-block sized. Quench heads (either 2V or 4V) will jack the compression ratio up to 2 points over your stock open-chamber heads (8:1 up to 10:1) which increases the power but requires premium fuel and much care in setting ignition timing, valve clearances etc. 2V quench heads will increase low end power and throttle response noticably over 4V quench heads since the ports are smaller so fuel/air velocities are higher. Either will pull strongly at 6500 if the cam, springs, carb & compression etc are coreectly chosen & assembled. Dyno tests show that for street engines, the Edelbrock 'Performer' dual plane intake can equal or exceeed power from most open-plenum intakes and may be better mid-range as well.