Originally Posted by 69307/350Chevelle
Same kind of question here. I've taken everything out and cleaned up the whole A/C system, new blower motor, etc. I know the car has a 40 year old design, but is there a more powerful blower motor that might make it match today's late model standards. My friends new Civic A/C feels so nice, are new cars systems just better at sealing in cool air?
Newer cars are just better designed for better airflow and volume.
Back in circa 1970, most GM cars were known to be rather wimpy as far as airflow out of the ducts, except on High Blower (Thus the High Blower Relay to put as much power as possible to the motor). Then they were only "kinda" wimpy. Chrysler products were even worse at that time. Ford was the only one back then that could boast that the output from the dash vents could "blow your hair back". Even they weren't up to todays expectations.
The High line GM cars (big Buicks, Olds, Etc) were better than the Low or Intermediate Line cars for airflow, but even they were not what you would expect today from even a "cheap" car.
Cars of the 40's and 50's had very poorly designed airflow (heater) systems that were just barely better than nothing. The systems of the 60's and 70s were comparatively far superior performers as the years progressed, but surely not even good compared to today. Fast forward to the 80's and they were better yet, but still not up to todays standards. Only in the late 80s and into the 90s did GM produce MVAC systems that compare to today's systems. That same progression held true with the other manufacturers, but GM historically has always had the "wimpyist" airflow systems as compared to the "other guys". Actually, that still seems to hold true even today IMHO. The difference just isn't as noticeable.
There might be ways to improve the airflow of those older cars, but I've never delved into it.
Today, the best you can do is meticulously seal leaks in the ductwork, make sure everything is nice and clean, and make sure the blower motor and it's wiring is up to par on these older cars. They were great performers compared to their predecessors, but you will never get 2009 performance out of them.