Fire brick area

[Diesel Pro]

I have a Wes Fab 2x4 evaporator that is kind of an entry level typical arch. The unit came with insulation "board" to line the entire inside. There is enough firebrick to do the main firebox area but not up the tapered section. When I asked my dealer if I should add brick up the taper he said not worth it. Curious if others agree or if I should look to add more brick?

[wmick]

Went through the same decision recently... and I decided to just go ahead and do it because it cant hurt...
I've always understood the purpose of fire-brick was, not only to insulate, but primarily to "reflect" the heat back at the fire... promoting the efficient and complete combustion of all the un-burnt gasses. Theoretically I would think that most of the burning should happen right in the firebox, but I've read lots on here about flames coming out the stack... so there's obviously some burning still happening under the pans.... I think the fire-brick would definite do some good... Just not sure how much.

[wiam]

When I burned wood my concern was damaging my blanket. I had brick over anywhere wood could hit. This included sides of firebox and ramp. There was only blanket under back pan. Seemed to make heat up/cool down faster white less brick. At first it was all brick.