I'm a stock purist and the PO of my XR7 did not keep the rubber distributor boot. I found a nice one at the local pick-n-pull but a discussion thread on a 3rd gen Mustang forum claims it traps heat and leads to early failure of the TFI module. Any thoughts?
(http://i750.photobucket.com/albums/xx143/kafer79/Boot_zps20b82888.jpg) (http://s750.photobucket.com/user/kafer79/media/Boot_zps20b82888.jpg.html)
My Thunderbird has always had one. It's still running the 26 year old factory TFI, for what it's worth. The TFI sits below the boot. I have no idea how it would trap heat in the TFI when the module sits below the boot.
Did these only come on the multiports? Don't think I've ever seen one on a CFI or Carb.
Mine has one, and it fits above the TFI anyway. I really doubt that as hot as the engine as a whole gets, that rubber cover is going to make the difference. It's never been too hot to touch after bringing the engine up to operating temperature.