[tehdrizzle]

I know that the big blocks take more to cool and I'm hoping that I've got something down that may be able to do the job. This is what I'm thinking;

-trim stock radiator shroud
-Chevelle radiator shroud
-Chevelle "Summit Racing" radiator
-5-blade flex-a-lite fan
-160 degree thermostat

Will this keep the motor in happy temps or do I need something else? It will be a GM Performance 454 H.O.

 

[veno]

ok.. a summit direct replacement aluminum will do just fine... be sure to get a high flow water pump... a 160 stat? I think 180....

a 17" 5 blade fan should move plenty of air.. use the stock Nova shroud...

My son has a much hotter 468 that the ho 454 your looking at...

it has a weiand hiflow aluminum water pump, and a direct fit summit aluminum... with a 180 stat it runs a solid 195 all day even in 100 degree weather

 

[chuckha62]

If that fan is a "flex" fan, I wouldn't do it. I have never seen a flex fan outperform a stock clutch fan keeping a car cool.

 

[tehdrizzle]

ok.. a summit direct replacement aluminum will do just fine... be sure to get a high flow water pump... a 160 stat? I think 180....

a 17" 5 blade fan should move plenty of air.. use the stock Nova shroud...

My son has a much hotter 468 that the ho 454 your looking at...

it has a weiand hiflow aluminum water pump, and a direct fit summit aluminum... with a 180 stat it runs a solid 195 all day even in 100 degree weather

Veno, as in stock do you mean stock shroud for the 396 or stock for the 350 radiator?

 

[veno]

Veno, as in stock do you mean stock shroud for the 396 or stock for the 350 radiator?

350..


what you have to look at is crossectional area of the radiator..a standard 4 core copper and brass radiator has 3/8" tubes and have to be thick to with stand the pressure... 4tubes X .375"= 1.5" of area.. where as a 1" 2 core aluminum the tubes can be thinner allowing faster heat transfer and wider because the aluminum alloy is a stronger metal than the brass...

so 2tubes X 1" = 2" in surface area.... you can see you get 1/2" for surface area with the aluminum and its a thinner tube also....

a SBC shroud and direct replacement radiator will cool the HO 454 just fine... no need to get all fancy here...

 

[tehdrizzle]

350..


what you have to look at is crossectional area of the radiator..a standard 4 core copper and brass radiator has 3/8" tubes and have to be thick to with stand the pressure... 4tubes X .375"= 1.5" of area.. where as a 1" 2 core aluminum the tubes can be thinner allowing faster heat transfer and wider because the aluminum alloy is a stronger metal than the brass...

so 2tubes X 1" = 2" in surface area.... you can see you get 1/2" for surface area with the aluminum and its a thinner tube also....

a SBC shroud and direct replacement radiator will cool the HO 454 just fine... no need to get all fancy here...

Awesome, thanks for the info. Wouldn't the pump that comes on the motor work?

 

[veno]

Awesome, thanks for the info. Wouldn't the pump that comes on the motor work?

should... but just in case keep the high flow pump in the back of your mind

 

[tehdrizzle]

should... but just in case keep the high flow pump in the back of your mind

Okay, just one more question. Should I get the larger 31" long radiator or the smaller 23" long? They have 2 at Summit listed as direct replacement. Should I get the larger one and cut my radiator support or go with the smaller direct replacement and not cut the radiator support?

 

[71SS454]

First off, unless you're using a short waterpump there's no room for a clutch fan in a Nova.

Now, here's my set up. I'm running a pretty healthy BB in my 71. I use a Flow Kooler iron water pump, A solid bladed steel 17" fan bolted directly to the waterpump, no spacer, a Summit universal 19x22 aluminum radiator, stock pulleys, a stock small block fan shroud that I had to modify slightly to fit right, and that's it. I don't have a thermostat in the car right now, but going down the higway at 3100rpm with the outside temps in the 70's the car ran too cool. It was only 140 degrees. Sitting in traffic it only went up to around 170-175, so I need to add a thermostat to mine, but as you can see, it's a very simple cooling system and it works very well. This would cool your engine easilly. Here's the fan I run:
http://www.summitracing.com/parts/DER-17317/

 

[tehdrizzle]

First off, unless you're using a short waterpump there's no room for a clutch fan in a Nova.

Now, here's my set up. I'm running a pretty healthy BB in my 71. I use a Flow Kooler iron water pump, A solid bladed steel 17" fan bolted directly to the waterpump, no spacer, a Summit universal 19x22 aluminum radiator, stock pulleys, a stock small block fan shroud that I had to modify slightly to fit right, and that's it. I don't have a thermostat in the car right now, but going down the higway at 3100rpm with the outside temps in the 70's the car ran too cool. It was only 140 degrees. Sitting in traffic it only went up to around 170-175, so I need to add a thermostat to mine, but as you can see, it's a very simple cooling system and it works very well. This would cool your engine easilly. Here's the fan I run:
http://www.summitracing.com/parts/DER-17317/

So I should be fine with the smaller radiator. I assume you didn't cut the radiator support to fit?

 

[veno]

http://www.summitracing.com/parts/SUM-380458/?image=large

$279.95

Brand Summit
Manufacturer's Part Number SUM-380458
Part Type Radiators
Product Line Summit® Direct Fit Aluminum Radiators
Summit Racing Part Number SUM-380458
Radiator Style Crossflow
Overall Width (in) 25.375 in.
Overall Height (in) 18.625 in.
Overall Thickness (in) 2.250 in.
Row Quantity Dual-row
Radiator Finish Natural
Radiator Material Aluminum
Transmission Cooler Yes
Inlet Location Upper driver side
Outlet Location Lower passenger side
Core Height (in) 18.250 in.
Core Width (in) 20.750 in.
Tube Size 1 in.
Fan Included No
Quantity Sold individually.
Notes Cooler bosses fitted with 1/4 NPT fittings.



Application


Universal No
Make CHEVROLET
Model NOVA
Beginning Year 1968
Ending Year 1974
Engine Type V8
CID 350
Liter 5.7
Engine Size 5.7L/350
Engine Family Chevy small block Gen I
Transmission Automatic

 

[71 Chevy]

get the wider radiator. it fits a lot of dual aftermarket electric fans.

 

[71SS454]

Yep, The radiator Veno posted is it. Didn't have to trim the cradle at all and use the stock upper mounting plate as well. All I had to do was trim the upper rubber isolators a little bit before I bolted the plate down.

As for the fan shroud modifications, those were simple as well. Since I used the correct big block frame mounts, I had to move the shroud over 1/2 inch towards the passenger side of the car. All I did was trim off the lip of the shroud on that side, then trim up the side of the shroud so thst it fit over the tank while allowing the shroud to sit tight against the radiator, then redrilled two new upper mounting holes 1/2 inch over and mounted it. Really simple.

 

[tehdrizzle]

Great info in this thread! Thanks everyone for your help!

 

[Michael]

Cooling...............

Id say you are definatly on the right track as far as knowing the BBC can sometimes be difficult to cool. I'm running a Fluidine ( 1969 Camaro radiator in a 1966 Nova, cooling BBC 402 ci. ) The radiator has " three " rows of 1 inch tubes. ( equaling more that a 4 core with 1/2 tubes ) ( but the fluidine radiators are not cheap ) . A GM five blade " clutch" fan will pull more are that a flex fan. ( if thats not enoght fan you can always go to a seven blade GM fan. ( I probably could have went with a four core brass for alot less money , but wanted an aluminum rad. ) BTW.. I did have to take the bumps out of the radiator support to fit a 1969 Camaro radiator in a 1966 Nova, but it was really worth the effort .

 

[68chevyll]