The 58 has a 454 in it.....regular exhaust manifolds, mild cam, HEI and a quadrojet.......what might an optimum engine temp on the highway be for a big block?
I think it should be around 220! Just kidding, I just want to say, How are you dude? ANd happy 4th. Love Jimmy
My '55 with a 402 big block, stock manifolds, comp 260H and HEI runs 180 on the highway. In really slow traffic it will get up to 195 on a hot day (thats 80 to 90 here) with the air on. It took alot of work to keep it in that range. I built a new bulkhead that will accept a 4 core cross flow radiator from a 70 caprice, built a shroud with a 19 inch steel mechanical fan. I also have 2.73:1 rear ratio which is really easy on the engine at highway speeds. The stock radiator would cool the big block okay. I changed because I figured more cooling capacity wasn't going to hurt anything, especially with a/c. Just make sure you use the biggest fan that you can fit in the area. My current setup with a 15 inch fan and shroud would boil over if I got caught in traffic on a hot day. Dave
we put what we thought would be a big enough radiator with a flex fan and a shroud.....it doesn't boil over but it does get up to around 210-220 degrees. that's on the highway moving.....
I had a 66 chevelle with a 468 and it ran around 200. I put in a griffin alum radiator and an elec 16" fan with a high flow thermostat 160 and it would stay around 180 in traffic. My 2007 GMC with the 6.2L runs 210 so who knows man that's hot I guess if you run good oil it will Handel the high temp.
I've got a 454 in my 41 and it runs at stat temp 190. This is with a mechanical fan and shroud, triple pass 2 core aluminum radiator. For backup when in traffic I have a 16" Spal pusher fan on a rheostat. Temps with this setup in a traffic jam have gotten as high as 210
The 454 that I have in my '88 suburban runs at 210 no matter how hot or how cold it is out. I have had it at the dealer and asked them about it and the mechanic said that it isn't unusual for it to run that way. I run a 195 thermostat in it year round. Larry
Depends on how much the block has been bored out. Core shift played hell with the cylinder wall thickness of the 454's. Bore em out and they run hot cause of thin ass walls. Bad thing is there's no fix. I learned this the HARD WAY>>>>.
200 isn't that bad if your temprature sender is in the head between the exhaust manifolds. If your temp sender is in the water passage by the thermostat it and you are on a 180 degree stat it may indicate annother issue. Typically higher temps on the higway are caused by either a lack of airflow through the radiator or a collapsing lower radiator hose. Also a bad head gasket, cracked block or head could cause this also. Assuming you have pressure tested your system to make sure none of those occur. While in park and the engine up to temp, hold the RPMs up to 2500 and check out the lower hose. Squeeze it a in different places and see if it pinches off anywhere. Other issues, like a later model truck with the smaller crossflow radiators there is an air dam under the core support that creates a low pressure area behind the radiator and a high pressure area in front to promote cooling. When these go missing air passes under the radiator and not through it because the space directly behind the radiator is pretty congested and does not promote good air flow.
I didn't have radiator issues in my '74 454. But the timing was a definite factor. Mine likes mild advance and dwell towards the low end of the range. I did put a new radiator in it right before I drove it 1500 miles in late summer from Texas to Ca. It ran 180 pretty much the whole trip at 55 with a trailer and bed ful of crap. It's also a stock bore with a mild cam. I gave the chasis away but kept the 454 because it ran so good.
One thing I forgot to mention earlier was JUNK the flex fan and get an aftermarket fan with ar least 6 blades. After rereading you second post and seeing the high temps are going down the highway it could also mean a radiator that needs rodding out. You should not be having problems like that with a radiator of sufficent size as you should have all kinds of air flowing through it. As ELpolacko mentioned make sure all air has to go thru the radiator not under, over or around.
thanks for the advice fellers!...... I have a stock mid sixties GM radiator in it now, but I'm replacing it with an aluminum crossflow......bottom hose is good. I also have to make something to keep the air from going under the radiator.......I'll post results later this week.....D
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