A local tuning shop in my area believes they found the limit of a standard bore 4g63 block -800whp. They knew that was the limit because once attained, they cracked the cylinder wall into the water jacket. Remember that this block was standard bore. While listening to the tech there tooting his horn, he said that once you are around 200hp per bucket, you need to start doing "tricks" to make the block stay together. It is possible to take an engine passed 800whp and over 1000whp.

They said that one of their "tricks" could be that they are going to fill the coolant area with cement except for a small portion below the head. If its going down the track in <9 seconds, does it really have a chance to get hot enough to warrent lots of coolant?