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did you ever have trouble with your 454 overheating ?

my wife wants a 73 Vette in a bad way (new front end, chrome bumper rear) and I finally found one with stuff on it she wanted, but she passed because someone told her they had overheating problems with 454 cars

just curious

72ragtop

I have a 72 BB, and live in Florida, No overheating issues yet including summer driving and beach traffic

Steve's74

Overheating on a big block (with the possible exception of a '68) is not a problem if everything is correct. This means the right coolant mix, a properly operating fan and fan clutch, the proper size radiator, and a fan shroud installed. All of the seals must be installed between the radiator support, radiator and fan shroud. These seals ensure sufficient airflow through the radiator. I have a '74 LS-4 big block, and while it hasn't had a lot of road time, it has run for as long as 30 minutes and never shown an indication to overheat.

Steve

7T1vette

But the primary reason for "hot-running" engines is that the old radiator is gummed up on the inside of the cooling fins. Remove that 'puppy' and have it cleaned [not just flushed]; that, and the items listed above, will cure any overheating issues. I wouldn't reject a great car like that for an overheating concern.

CheckeredFlag

thanks for the info

427SIXPACK

AND DONT FORGET TO INCLUDE THE THERMOSTAT & WATER PUMP..........
PS.
AND MY 68' BB NEVER OVERHEATS !!!

AAJC

I have a 71 BB 454.

I couldnt keep the temp below 110 (celsius) with the original radiator in it. Slow runs with frequent stops were thee only way I could drive it.

I put in a good quality aluminium radiator, new hoses, & repalced the thermostat. This has been the best money I have ever spent.

I have taken the car on a 1000 km (600 mile) trip on a very hot day & the temp didnt shift over the thermstat rating. ( about 92)

jr9170

My 70 ran a little hot,changed the radiator and water pump,promblem solved.Do Not let what someone says discourage you in buying the 454 you are looking at.

jim2527

I installed new seals between the radiator and support and shroud and radiator. The radiator/support sealing was OK but there were massive gaps between the shroud and radiator. I wouldn't doubt that more air was coming through the gaps than through the radiator. I picked up some pipe insulation foam from Home Depot and filled the gaps.

Like everyone has said, if all components are working properly you'll be OK with a BB.

danthony

Kap142

I too have a 72 BB. I run a Dewitt radiator and have no cooling problems, ever. As 72Ragtop mentioned I also live in Florida so the summer lets itself be known.

Ironcross

A bubba free BBC or any other Chevy engine never overheats beyond OEM replacement parts. It`s only where one believes incorrectly that they are better at developing a cooling system than the Generals staff that merely engineers and makes the Vettes. .

427SIXPACK

WELL PUT !!

carbster09

My LS-5 has had alot of time and effort put into the cooling system. I have a DeWitts Rad, etc ... etc. It runs "ok", in HOT Houston weather. Just ok..... until I get stuck in traffic. I basicly avoid areas and times when I even think traffic will be bad. And, before everyone tells me that these cars are just fine with stock parts, I have replaced everything. The DeWitts Radiator helped, as did a new fan shroud and all new seals. The Stewart water pump and running an 80/20 helped too. Just be prepared as they don't run cool.!

Still I wouldn't trade my 454 for any Small Block!

carbster09

Ironcross

Well heres one I know dont overheat. People that never owned a Vette from new for some reason go overboard and spread rumors about Vettes for whatever reason it relates too. This year does this and that year does something else and so on. This one didn`t get hot when new and there isnt any reason for it to suddenly get a reputation of overheating as it approaches a certain age. Thats a bunch of Oh, and this one hasn`t had any problems because we have had it since new. No smart *** ever got his hands on it to screw it up...

rjm65

I used to own a '73 LS-4 with A/C. I lived in south-east California, 120 degree temps in the day during the summer.

The car would run fine on the highway, but would get to about 210-220 in city driving, with the A/C on. .

Heat soak seemed to be a bigger issue. After shutting it down, the temp would be almost in the red when you came back to start it up (such as stopping at 7/11 for a Slurpy).

It is very important that the fan shroud, fan clutch, and every seal and gasket that forces air through the radiator be in place.

The LS-4 never overheated, but it also never ran as cool as the other two small block Corvettes I've owned.

HamadUP

I just cant believe the big block corvettes would survive in a hot place (like my place, where we get 100F+ during summer) with all stock cooling system, its just not sufficient (I am talking here about big block with A/C on, it must be on since its a hot place!). In my humble experience, I cant even find it sufficient with A/C off!. I now have a Dewitt aluminum radiator and dual spals, and I don't have any cooling issues.

Bottom line : If you live in a hot place, upgrade your cooling system, otherwise, just enjoy the raw power and muscular sound of a big block!

7T1vette

Unless you are "putting the pedal down" [more than you need to], a BB won't generate much more heat than a SB. Some additional friction due to the difference in part sizes.... At idle, it will generate about 10-15% more than SB, just due to cylinder volume. If the [stock] radiator is in good shape and there are no problems with water pump, etc., there should be no problem....with the possible exception of sitting idle for a significant amount of time, A/C turned on (MAX), sitting in the sun on a summer day in Phoenix (110F+). But, I think that would be a problem for the SB engine, too. Have the radiator professionally cleaned--and repaired, if necessary--and there should be no problem. If you live in a hot environment, I would also recommend going to a 160F thermostat. {Your car will likely stabilize at about 180F, but might run a bit cooler than that at cruising speed.}

jim2527

I think most people dont have a clue as to what 'normal operating temperature' is. Low 200's is normal.

7T1vette

Jim....

You are obviously a young fellow. Low 200's is a 'normal' operating temperature....for US autos built after 1973. That is when the thermostats were changed from 180F to 195F for emissions control reasons. Prior to that, GM V8 engines (1955 thru 1972, at least) had 180F thermostats specified...because that is what GM determined to be the best average operating temperature during their development activities. Operating any Chevy V8 at higher than that temp is less than optimum...but it is likely required for computer controlled cars which won't leave their "start-up" mode unless the engine temp is above 190F.