[Bob Parmenter]

Tom,

Re: your question on why "street" gasoline is more volatile than race gasoline; street gaso is formulated to accomplish a variety of things that it will experience in the consumers usage (read, compromises). One of the situations it needs to deal with is cold strarting, where volatility is important (although less so with FI systems). Race gas guys don't much care about cold starts for obvious reasons.
Ditto on the phenolic spacer.