I've seen several TRs with a heat shield as you describe and the
>owners said they worked fine. I decided on the header wrap because it
>keeps the heat in the header tubes which keeps exhaust gas velocity
>high, theoretically increasing flow. It also gets the heat out of
>engine compartment completely, rather than simply redirecting it. The
>disadvantages include faster deteriation of the header due to more heat
>and the wrap's potential to hold moisture, and possibly hotter feet for
>my passenger.
With no malice towards the orginal author, I a not sure about having high
temperature increasing the gas velocity. Isn't it true that for the same
mass flow rate highter temperature will CAUSE higer velocites due to the
greater VOLUME flowing through the exhaust. With the greater volume you
will have more back pressure. Less back pressure is what you really want.
The use of heat wrap is most likely for the protection of other equipment
mounted near the exhaust?
Flame suit on, Flame away
Dave Simpson
61TR3B
76 Spitfire, now reassmebling after new paint, lots of FUN!!
can't wait to drive it now!!
|