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Air condition air intake box mod

TG
tom geiger
Thu, Sep 2, 2021 2:13 PM

I just had a question on the air intake box specific the the cut I make on the air intake area and firewall apparently around the glove box area.  Am
I thinking correct that there will be 2 surfaces that get cut?  1st will be the metal air box and behind it will be the firewall?  And if thats the
case do I need to seal somehow between the two surfaces to make sure it draws air from the box and thus the air passing over the evaporator only?

Thanks,
TG

Tom Geiger
76 Eleganza II
KCMO

I just had a question on the air intake box specific the the cut I make on the air intake area and firewall apparently around the glove box area. Am I thinking correct that there will be 2 surfaces that get cut? 1st will be the metal air box and behind it will be the firewall? And if thats the case do I need to seal somehow between the two surfaces to make sure it draws air from the box and thus the air passing over the evaporator only? Thanks, TG -- Tom Geiger 76 Eleganza II KCMO
JR
John R. Lebetski
Sat, Sep 4, 2021 2:26 PM

My 2 cents is if you have a 76 with add on max lower duct is leave it alone.  If you drill for “recirculate only” you lose fresh air VENT function
for driving in cool weather where you don’t need compressor. This air can also be warmed as needed.  Also heater and DEF will be no fresh air
leading to steamed up windows in rain situation. This means having to run compressor in DEF and fuel waste.  Also outside air positive pressure going
down road is good for not drawing in sewer odors. Wes did a full article on this back when the Cinnabar news letter was in print.
Lastly with recirc only, you lose the “65 MPH free ram air effect” to get more output from the dash vents as the squirrel cage is being force fed
by the frontal area high pressure.

John Lebetski
Woodstock, IL
77 Eleganza II

My 2 cents is if you have a 76 with add on max lower duct is leave it alone. If you drill for “recirculate only” you lose fresh air VENT function for driving in cool weather where you don’t need compressor. This air can also be warmed as needed. Also heater and DEF will be no fresh air leading to steamed up windows in rain situation. This means having to run compressor in DEF and fuel waste. Also outside air positive pressure going down road is good for not drawing in sewer odors. Wes did a full article on this back when the Cinnabar news letter was in print. Lastly with recirc only, you lose the “65 MPH free ram air effect” to get more output from the dash vents as the squirrel cage is being force fed by the frontal area high pressure. -- John Lebetski Woodstock, IL 77 Eleganza II
TG
tom geiger
Tue, Sep 7, 2021 12:46 PM

I guess I could do part of the mod and not the recirculating part and see how that cools.  The recirculation part of the mod seems pretty straight
forward and can be done at a later time if cooling is not enough.

TG

Tom Geiger
76 Eleganza II
KCMO

I guess I could do part of the mod and not the recirculating part and see how that cools. The recirculation part of the mod seems pretty straight forward and can be done at a later time if cooling is not enough. TG -- Tom Geiger 76 Eleganza II KCMO
RK
roy keen
Tue, Sep 7, 2021 4:28 PM

For me opening up a recirculating hole in the firewall and blocking the outside air intake made a huge improvement in the cooling ability in my 1976
coach lots of cold air coming out of the bottom add on ducts. I don’t need to deal with high humidity here in dry nevada we have almost no humidity
but we do have high temperatures as it is mostly desert. I would do the modification then unblock the osa in humid weather .

Roy Keen
Minden,NV
76 X Glenbrook

For me opening up a recirculating hole in the firewall and blocking the outside air intake made a huge improvement in the cooling ability in my 1976 coach lots of cold air coming out of the bottom add on ducts. I don’t need to deal with high humidity here in dry nevada we have almost no humidity but we do have high temperatures as it is mostly desert. I would do the modification then unblock the osa in humid weather . -- Roy Keen Minden,NV 76 X Glenbrook
TG
tom geiger
Wed, Sep 8, 2021 12:13 AM

That was my thought Roy was to put a adjustable intake door on the outside of the box to allow to either completely block off outside air or on humid
conditions adjust the opening as you say.

TG

Tom Geiger
76 Eleganza II
KCMO

That was my thought Roy was to put a adjustable intake door on the outside of the box to allow to either completely block off outside air or on humid conditions adjust the opening as you say. TG -- Tom Geiger 76 Eleganza II KCMO