Changed from 2 small fans to one 16 incher...

[Sledge]

....on BDR 168. Also went with a slightly larger all-aluminum radiator as the old one was leaking. Anyway, got the fan shroud from Reg, mounted the new radiator, Spal 2400-something cfm fan, and I'm happy to say, no leaks! But----

Prior to the changeout, while going down the feeway with fan(s) off, the temp would stabilize at about 87 deg C. Now it wants to run at 90 to 92 deg C. If I turn on the fan the temp goes down to 80 to 85 deg C. In stop and go traffic the temp will run about 90 to 95 with the fan on all the time.

None of the hoses are blocked or kinked, the air has been burped from the system, and yet now with a bigger fan and radiator it is running hotter. I have not made any timing changes which is 34 deg total, all in by 2500.

Do I need to cut in some flapper doors in the radiator shroud to allow more air through at speed?

I've got the fan hooked up to one of the original two 30-amp relay/circuit, with a 30 amp fuse. The Spal instructions call for a 30 amp fuse maximum. The fan draws around 22 amps when in operation. Is this system getting the necessary power to the fan? If not, what do I need to change?

Finally, I'm running a 180 thermostat. Would a 160 be better? It gets into the 90s often in summer months and occasionally into the hundreds, but the rest of the year it is mostly in the 70s.

Thanks for any and all help