Ive got some updates on my engine heating problem. First let me say before I did any testing tonight I took the car out for a 20 mile drive (again the outside air was around the mid 60's.) with the new 2.75 holes in the shroud. Total of 6 of those holes and they were in the dead head area of my shroud. For the first time the temps stayed lower then in the previous drives and it was a much longer drive. The highest that it got during the drive was 215. When I was moving at 45+ mph the temps would actually run at around 205. As soon as my speed dropped the temp would go to 210-215. The best news was that if they went up I could drive faster and they would come down, but not lower then the 205.
I did not idle the car at all tonight just the drive.
Now for the test results.
Engine hot probably a soak of 170*-180*.
Cylinder Compression Cylinder leak%
#1 150 10%
#2 150 9%
#3 150 9%
#4 150 8%
#5 150 9%
#6 150 10%
#7 150 10%
#8 150 9%
Before I did these tests I removed the fan belt and thermostat and filled the intake to the top with coolant. During the cylinder leak test there were no bubbles in any of these cylinder tests which made me feel much better about a blown head gasket possibility.
While I have the plugs out I thought I would put the pics up and let me hear what everyone thinks of them. They now have maybe 30-35 miles on them and all miles are driven under 3k.
The next 2 pics are passenger side in order 2 4 6 8
View attachment 1715328654 View attachment 1715328655
The next 2 photos are the drivers side in cylinder order 1 3 5 7 View attachment 1715328656 View attachment 1715328657
To me they might be slightly lean but they are turning a light tan to brown and again they only have 30-35 miles on them. #2 looks a little dark.
I am running a 750 that has been reworked by Sean Murphy in California. He built this for all the specs that I used during the engine build. Im running a mallory fuel pump and regulator. Gauge says its around 6.5-7 at startup but as temps build the fuel pressure drops to around 5 psi? Is this normal. Could heat be vapor locking the fuel feed causing a lean condition. It will act as tho its vapor locked after it gets hot and has sat for 15 minutes. Seems as tho it may even perkulate the fuel. ???? I will be posting in the carb section about setting up a 4 corner carb as I have no experience with one of them at all.
I still need to do a few more tests, first is the radiator flow test that one member mentioned.
I still pan on trying my original 4 blade fan but i dont know if it had a shroud from factory and I dont have one if it did.
I also will be changing out the pulleys and going to a 5" water pump pulley and 6" crank pulley to make the water pump overdriven.
Let me know your thoughts and i will go back and see if I am missing anything I should do that has been mentioned previously.
One last thing, please keep this thread on track for overheating. Greatly appreciated!
Thanks Rod
