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[C1] 56/57 blower motor air flow

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Old May 19, 2026 | 04:49 PM
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Default 56/57 blower motor air flow

Working some kinks out on my ‘56. When I run the heater/defroster blower I can hear and feel both the low and high speed airflow; however, both do not move a lot of air. The motor is in great shape and the duct work under the dash is pretty tight meaning not a lot of air leaked. Has anyone switched to a better motor, squirrel cage, etc. to improve their airflow. If so what did you use? Thanks.
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Old May 19, 2026 | 05:06 PM
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Does the 56 have a **** that says "air" that you pull out to open the flapper to allow air in under the hood like the 58-60? If so, it needs to be pulled out to allow air into the fan housing.
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Old May 19, 2026 | 05:06 PM
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Is the air valve (on front side of firewall) open to allow air to flow from the fresh air hose?
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Old May 19, 2026 | 05:08 PM
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Google says it does have one. So should the owner's manual if you have one.

For a 1956 Corvette, you can choose between two main components commonly referred to as the "air ****": the fresh air cowl vent **** or the "AIR" dash pull cable. You can find exact reproduction parts at specialized retailers like Zip Corvette or Top Flight Automotive. [
, 2]
Specific details for both parts include:
  • Cowl Vent / Fresh Air ****: This chrome-plated die-cast **** mounts to the cowl vent opening lever. Reproductions generally cost between $15.00 and $25.00.
  • "AIR" Dash Cable & ****: This is the control cable located on the dashboard that regulates the fresh air intake. Original, clean, used examples often sell for around $250.00.


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Old May 19, 2026 | 06:03 PM
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hold on a second
This may be new to me, First off i come from aback ground of old VW beetles.
so when we talk heater systems they can be pretty much the wort out there.
I have evrything working with new hoses and i can here the fan but no airflow, do i have to open the flap (Air) in order for it to fully work?
If so i was completely clueless and some one just made my day if that's the case
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Old May 19, 2026 | 06:32 PM
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Good advice. I thought air valve was open, but will go out to garage in next day or so and confirm
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Old May 19, 2026 | 07:18 PM
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'56 Corvettes before VIN #200 (1200) had a recirculating heater like the '55. If your '56 is one off these, it will not have an Air pull cable, or a fresh air hose in the engine compartment. These heaters do have a lower air flow rate, especially at speed.
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Old May 19, 2026 | 11:27 PM
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Originally Posted by rusty60
--------------------------------------------------------------------- do i have to open the flap (air) in order for it to fully work?
-----------------------------------------------------------------------------------------

yes, ABSOLUTELY!!!!!!!!!!!!!!!!!!!!!!!!!!!

Last edited by DZAUTO; May 19, 2026 at 11:28 PM.
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Old May 20, 2026 | 04:35 PM
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VIN around 1500. Wasn’t aware of the earlier recirculating heaters - thanks
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Old May 20, 2026 | 06:08 PM
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Default Picture of 1956 VIN #10 Blower

Originally Posted by Todd H.
'56 Corvettes before VIN #200 (1200) had a recirculating heater like the '55. If your '56 is one off these, it will not have an Air pull cable, or a fresh air hose in the engine compartment. These heaters do have a lower air flow rate, especially at speed.
I saw 1956 VIN #10 at an NCRS meet on Saturday. Here is a picture of that early recirculating blower.

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Old May 20, 2026 | 07:12 PM
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Nice find Charles. Which event?

Looks like it had power windows and power top.

All early 56's had mandatory power tops and 2x4 bbl carbs.

Just noticed.... I wonder why the tan power top feed wire at the circuit breaker isn't attached.


Last edited by rich5962; May 20, 2026 at 07:35 PM.
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Old May 21, 2026 | 08:49 AM
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The fresh air heaters in solid axle Corvettes are really great heaters. I drove a '56 with a fresh air heater and a '62 through some very cold Minnesota winters many years ago. They work so well that I didn't even need the fan when I was driving over about 35mph. The old cars have various shortcomings, of course, but least you don't have to be cold in one.
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Old May 22, 2026 | 10:40 AM
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Originally Posted by rich5962
Nice find Charles. Which event?

Looks like it had power windows and power top.

All early 56's had mandatory power tops and 2x4 bbl carbs.

Just noticed.... I wonder why the tan power top feed wire at the circuit breaker isn't attached.
NCRS So Cal Chapter spring meet.

Yes, Rich, it had power top and power windows. The top equipment was there but the top was not functional so the owner presented it as a hard-top car. First time he had it judged and it scored TopFlight!





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