Head hurts, reading soo much info! It seems the best option for my base rsx is to get a k24a1 block and a k20a2 (type s) head. So, like the hottie marsvoltafan (great band), I am wondering how the 'numbers' and install would go with a k24a1? Ack! I am so confused. I thought that the k_ _ was the block and the a_ was the head for the k series?? Sigh, if I get k24a1 block it goes together with k20a2 head yes?? What would be the benefit of using a k24a4 block?