Pontiac Firebird 455 Cooling Upgrades | How to Stop Overheating in Classic Muscle Cars

In this video, I walk through the complete cooling setup on my 1967 Pontiac Firebird Convertible with a 469ci Pontiac 455 engine and Chevy 700R4 transmission. Keeping these big Pontiac motors cool isn’t about one “magic bullet” fix—it’s about a combination of upgrades that work together.
I cover every detail of my Firebird’s cooling system, including:
Open hood scoops & Mustang hood vents for better airflow
Aluminum Cold Case radiator & Lincoln Mark VIII electric fan with DC Controls
Mishimoto transmission cooler with dedicated fan (big drop in temps!)
Radiator hose spring, high-amp alternator, and GM water pump setup
Edelbrock 180° thermostat vs. other thermostat options I’ve tested
Undersized pulley to increase coolant flow
421 mod for improved coolant routing in Pontiac engines
Timing setup and how it impacts engine temps
Coolant mix, radiator cap pressure, and additives like Water Wetter
You’ll see real-world driving results in Michigan summer heat, with the Firebird holding around 180–190°F under most conditions—but pushing higher on hot days in traffic. I also preview my next upgrade: switching from the Lincoln Mark VIII electric fan to a heavy-duty GM 7-blade clutch fan.
If you’re building or tuning a classic Pontiac V8—whether it’s a Firebird, GTO, Grand Prix, or any 455-powered car—this video will give you proven cooling tips and mods that really work.
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Chapters:
0:00 Intro – Firebird Cooling System Overview
1:20 Hood Vents & Airflow Mods
3:00 Radiator, Electric Fan & Controller Setup
6:30 Mishimoto Transmission Cooler
9:15 Water Pump, Pulley & Radiator Hose Tips
12:40 Thermostat Testing & Best Results
16:00 Internal Mods – 421 Coolant Passage Mod
20:00 Timing Setup for Cooler Temps
24:00 Real-World Driving Test & Temps
30:00 Electric vs. Clutch Fan Preview