Running hot.BBC 454 30 over,new 3 core rad.water pump all new hoses,180 thermostat,timming around 8-10 degrees new fan and fan clutch,with a electric fan in front,running a fan shroud,gauge reads 220 degress,its a auto gauge can it be off that much? can't see why this motor is running so hot and thats on a 75 degree day.  

even though you have a new water pump your water pump could have problems with its berrings they dont allways leak as far as my experience goes they dont have to, if it was a remanufactured waterpump the blades do spin but not as fast as the pulley, they sometimes can have enough pressure to keep the engine cooled a little but not enough to keep it from running hot, not letting it seem like a problem. thats my best guess but i'm not really experienced i have only built one engine  

Thanks for your thought's  

My buddy built a 454 a few years ago and had overheating problems. He ended up putting a smaller drive pulley on the water pump to drive the pump faster. I think it was part of  a performance pulley kit. Don't know which one. I know it solved his overheating problems.  

I'd also confirm/ensure that the radiator is designed for a big-block.  Being a 3-core, it may not be. 

You can spin the pump faster, install a lower temp thermostat, etc.  Yet, if you have a radiator designed for something smaller than a big-block you're barking at a tree.

What's this in?

Bogie

i also have a 454 (thats .060 over) built for the street/strip.  i had a 180 thermostat and it would run a little hot an my upper rad hose would look like it was about to explode with pressure, so my next move was to put a .625 restrictor plate intstead of a thermostat, it runs at about 160-170 cruising and never goes above 190 in traffic.  i also have a four core alum rad, alum mech water pump, and an electric fan behind the rad.  i have the fan mounted about .125 away from the radiator on some aluminum strips from the hardware store.  dont use the through-the-radiator way.  i have the march v belt pulleys, not sure what the ratio does to the water pump though.  i actually took the bypass hose off from the water pump to the intake and it seems to run a little hotter, so i will be putting that back on.  i just did this for expermentation.  one mistake i made when i built my other engine was i had the fan turning the wrong way.  i know its a rookie mistake, but i am a rookie!  but check that.  jetting and timing will also make it run hot.  i have a 750 holley dp and actually felt a difference in headers radiant heat after jetting it correctly (they get cooler).  i run about 14-16 init and 34-36 total timing, no vaccum adv.   hope this helps!  

I would not run a thermostat and instead run a restrictor.  The thermostat can fail at the worst of times.  Unless you have computer issues.  If the Thermostat is not a high flow unit this will also cause problems.  There should be a great deal of hot air from behind the fan shroud.  Check your electric fan to be sure it is pushing air from front to back.  Should be enough air without it, if not fan clutch. Good Luck!  

just a p.s.....i got a cylinder head temperature guage and my heads actually run at about 220 degrees without the bypass from the water pump to the intake.  they run about 195 degress with the bypass installed and the regular temp guage reads about 170-180 in both cases.  i have the regular temp probe in the intake by the water neck and the cyl head temp probe in the side of the head where the 1/2 pipe thread is (big block).  just thought someone would like to know because i looked everywhere and couldnt find info on it.