My car is a Hi-Tech with a big block. Since I began driving it, excessive engine bay heat had been an ongoing challenge for many years. These are most of the heat management steps I've made that have cumulatively worked to resolve the issue.
1. Glued two small rubber blocks under the rear edge of the hood. They measure 7/16" square by 3" long. They allow some underhood heat to escape.
2. Wrapped the primary header pipes from the engine block to the fender, with Thermo Tec 2" wide heat barrier. The pipes are mild steel and were Jet Hot coated, inside and out, in 1994. They've been wrapped for 24 years. I've had to re-wrap them several times, most recently last year. The pipes show no sign of any rust. The wrap reduced a significant amount of heat.
3. Installed a double insulated barrier between the master cylinders and the primary headers.
cobrakiwi makes these.
4. Several years ago I added 2 screens to each front inner fender panel.
