aknight_sa

Good day Guys,

i just have a question here regarding the above subject, i have long tube headers installed on my 97 Camaro with stock LT1 engine from the previous owner..

i was working on restoring most of what he did back to factory stocks.. and as i was looking for a manifold a mechanic told me that if i put the exhaust manifold on the engine will over heat as headers are better to release heat.. but i recall reading in a performance book that its the other way around as the exhaust manifold works as a heat sink on the engine which pulls off lots of the heat off the engine.


what do you think??

Wild Willy

Headers *may* lower your underhood temps, getting the hot gases out of there faster. Especially if they are ceramic covered. Manifolds being big chunks of cast iron hold lots of heat. Not sure how either will affect the engine temps, unless the headers increase flow so much that the engine leans out. It shouldn't, with O2 sensors and such, but it theoretically could happen.

bobdec

Agree w/above, however I'm pretty sure there are a lot of 'stock' F-Body's out there w/original manifolds that there not overheating. Is there something your mechanic saw that made him think you would have problems.

Injuneer

Headers generally increase under hood temperatures. A 1/4" to 3/8" of cast iron has higher heat transfer resistance than a 16-gage steel tube. Using cera-metallic coatings both inside and outside the header tubes will minimize the heat loss to the engine compartment, probably making them comparable to the stock cast iron manifolds.

There is no underhood temperature reduction from "getting the hot gasses out of there faster"..... typically a header tube has a larger cross sectional area than the corresponding header primary, so the velocity at any given HP level will be lower in the header primary.