Ben, I think that is dependent upon whether the shell is an XL or XLII. The XLII on a MH has a much greater area for cooling air flow essentially using the space behind the tag all the way to the rear. On the entertainer the XLII loses that 18" due to the longer wheelbase. The XL only has the shorter open area for cooling because on those shells the 18" area behind the tag is usually used for something else, such as the Webasto on my Liberty.

What all POG members should realize is Detroit (and probably Volvo) will certify the engine installation and the amount of horsepower will be dependent upon the ability of the coach to cool as required. At one time owners were getting their HP "turned up" but with no other modification to the coach or the cooling system. When the HP was needed such as climbing a long hill, if the coach could not get rid of the heat produced the computer just started removing HP from the engine which negated the increase in HP.

When a coach is sold by Prevost with a given HP, the cooling system for the engine can remove the heat produced so the HP is always available.