As far as the header wrap goes...
Header wrap traps moisture inside the wrap, and will corrode/rust uncoated headers. The heating/cooling actions creates condensation... not good on painted steel headers.
Now, if the headers are jethot coated (or simmilar ceramic) and it's a good coat job, then you should be fine running the wrap. It does reduce temps a lot, but don't wrap uncoated headers (coated inside and out is the only way to fly!). Generaly... I don't wrap headers unless it's going to be a purely track car.. they look gross and reduce the life of the header...
Are the borla headers stainless?
