I used a horizontal A/C condenser that was mounted under the rear of a 31 Chevy Sedan Street Rod. I did however mount it at a small angle to allow freon to flow from gas to liquid. Id like to see that radiator mounted at a similar angle(20-25 degrees) so there is no chance of an air pocket. What can happen is when the thermostat opens it could drain the block and leave an air pocket in the motor. This is just my opinion, I could be wrong, but that radiator is made to flow top to bottom leaving any air in the top near the cap.
Neat project though, Ilike the idea of big Tide box or maybe even a couple of large 12 packs. Good luck keep us informed.
By the way that A/C unit worked perfect in that drafty street rod, with 2 fans pulling down and out. I vented the running boards with several louvours to allow air. Drove that car from Florida to Syracuse one summer and Springfield the next.
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