Newly rebuilt 427 side oiler in a Hurricane. As I have been working through putting a few miles on the car and tuning it I continue to suffer an overheating issue that I can't solve. It runs nice and cool down the highway at 80-85C, but it jumps up to 100-110C at idle. I was at a local car show last weekend and it was suggested I needed a fan shroud to help out at idle. I ordered an aluminum shroud from JEGS and I also purchased a Zirgo 3650 cfm fan in lieu of the 2300 cfm that came from Hurricane. Trimmed up the shroud and installed it and the new fan yesterday, expecting a big improvement. Nope, worse. Headed out about 6PM last night (outside temp was about 90*)and she hit 100C at 50 mph before I got a mile outside the subdivision. I could keep it between 100-110C going down the road (ambient temps were 90and humidity was high) but I was pretty nervous when I finally parked it. The shroud killed the airflow at road speed and didn't help squat at idle. But the fan is clearly moving a tremendous amount of air, I can feel it at the back of the car on the garage floor when its running.
From a cold start it takes the car 7-8 minutes to get up to 85C. Beyond that, idling in the driveway, it will slowly climb to 100C, possibly beyond. I can cool the radiator with the garden hose and drop it back to ~90*C for a couple minutes, then it starts to slowly climb again. With the cap off I can see when the t-stat opens and coolant starts flowing.
Also, I bought this car turn-key minus from a guy that had put 1500 miles on it from new with an all-aluminum 482 KC Pond engine. He says he had zero cooling issues. I am running that same radiator and even using his hoses.
So:
- New engine with 250 miles that ran cool on the dyno and runs 80-85*C down the highway (without that shroud)
- Good
oil pressure, 55-60 at road speed, 25-30 at idle. After 15 minutes of warm-up
oil temps parallel engine temps, max out around 110C.
- New Ebrock water pump on the engine when built, bypass hose installed.
- Expansion tank was vatted, leaks repaired and pressure tested to 20 lbs.
- 180* hi-flow t-stat from Cobra Valley and a 180* electric fan temp switch from BeCool. Its on a 30 amp relay but I have since wired it direct and its starts with the car.
- 70/30 distilled/Dexcool with a bottle of water wetter.
- New Stant 16 lb radiator cap.
- Timing and carb mixture close enough that it seriously doubt it could be causing this.
Ideas? Thanks in advance.