As a rule of thumb, expect 20F below ambient on the worst days (humidity counts more than temp).
Your problem needs to be diagnosed by an independent shop with a stellar rep in HVAC work.
Above 95F here in Dallas, it is practically normal to have to run recirc in stop-and-go traffic. Usually takes us 4-5 miles to cool car (even the new one, the JEEP replacement, a LEXUS GS 330), and that is consistent with even the monster compressor cars of the 1950's (capacity to cool a house in the Imperial and Cadillacs until the work was taken over by the factorys from outside vendors whose regular clientele was rail and truck reefers. The difference with them was that, once cooled, you could pull the temps down into the 40's, a 50-60F change).
The late 1960's through mid 1970s Cadillacs were pretty impressive though, one of ours kept the car at 65F in 110F+ ambient on the highway [non-desert]).
Your problem could be a low charge (slow leak; shoot they all leak, only a matter of how much), or even a simple blend-air door problem/vacuum control problem.
UV tint helps, windshield screens REALLY help (my old Chrysler had an accurate aftermarket dash temp gauge to measure the interior, and it would pass max reading of 160F in fifteen minutes when stopped even with windows opened in July/August), and parking with the windshield away from the sun as the back window is usually smaller and only heats up the rear deck/seat in disproportion.
Helps, too, to open doors on both sides of car before getting in and starting, and then not turning on recirc getting underway until a minute or so has passed so as to expel all that superheated air.
Your problem needs to be diagnosed by an independent shop with a stellar rep in HVAC work.
Above 95F here in Dallas, it is practically normal to have to run recirc in stop-and-go traffic. Usually takes us 4-5 miles to cool car (even the new one, the JEEP replacement, a LEXUS GS 330), and that is consistent with even the monster compressor cars of the 1950's (capacity to cool a house in the Imperial and Cadillacs until the work was taken over by the factorys from outside vendors whose regular clientele was rail and truck reefers. The difference with them was that, once cooled, you could pull the temps down into the 40's, a 50-60F change).
The late 1960's through mid 1970s Cadillacs were pretty impressive though, one of ours kept the car at 65F in 110F+ ambient on the highway [non-desert]).
Your problem could be a low charge (slow leak; shoot they all leak, only a matter of how much), or even a simple blend-air door problem/vacuum control problem.
UV tint helps, windshield screens REALLY help (my old Chrysler had an accurate aftermarket dash temp gauge to measure the interior, and it would pass max reading of 160F in fifteen minutes when stopped even with windows opened in July/August), and parking with the windshield away from the sun as the back window is usually smaller and only heats up the rear deck/seat in disproportion.
Helps, too, to open doors on both sides of car before getting in and starting, and then not turning on recirc getting underway until a minute or so has passed so as to expel all that superheated air.
