Runing Hot

[70MC]

I have a 572 in a 70 Monte with a factory 4 core radiator with dual Spal fans. The temp will continue to climb at a speed over 35mph. The faster you drive, the faster it gets hot. It will stay at 180 at idle or driving slower than 35. Am i asking to much from a factory 4 core with a 572?

[Carnut1]

I was never a fan of electric fans. You have a huge engine on electrics with radiator that works great on a hot small block. Ambient air temp makes a difference and if you run an a/c condenser that makes a difference.

[427dart]

I would look at a better radiator like a Griffin 2 core which has much wider flow tubes,about 1 inch I think, and transfers more heat out of the water.
I have had mine for more than 10 years and it's still cooling well and no leaks.
Of course when it's bumping 100 degrees air temp nowdays hard to keep anything cool much less put out any power!!

[user-612937456]

May be a silly question but the fans make sure they are moving air the right direction? Also if this is an antique copper/brass radiator consider that the core tubes aren't restricted the ends can look good but the tubes can still have corrosion in them. Another thing is coolant flow speed like is your water pump moving the coolant too fast to radiate heat while in the radiator?

[wyrmrider]

copper conducts heat better than al
al is lighter
frontal area makes the biggest difference
#cores also
but also fin count
straight fins 16 fins per inch works great
however something does not compute
fans do not really help above 35 mph
is your core support sealed- all the holes
running a spoiler under the core support?
first follow up on the fans running backward
572 cu inches is not really relevant just cruising down the highway
in only takes so much HP to move a 70 Chevelle down the highway big block or small block
now road racing or towing would be a different problem
BTW work up on your heat transfer knowledge- lots of bs from the radiator mfg out there YOU have to understand

[peejay]

I never met a SPAL fan that I liked. They never seem able to move very much air. If you installed the very crappy shroud that comes with them (flat amuminum that sits maybe an inch from the radiator core) that is also going to be restricting air freeflow, you effectively will only have as much radiator area as the cutouts in the shroud.

An aside, the problem with CFM ratings is they don't tell you how much air it moves with a pressure drop, which is what you'll get with a radiator and A/C condensor and trans cooler in front of the fan. The SPAL fans I have seen/tried do not tolerate very much pressure drop, they had straight blade fans and low power motors so they were no good for actually pulling air through a radiator. But they are expensive and have an impressive-sounding name so people keep buying them.

Buy one of these and make it fit: https://www.summitracing.com/oh/parts/f ... odel/gt500

There is a connector available but you can also just use spade terminals and heavy gauge wire. No smaller than 10 gauge, preferably 8. Heavy duty relays required.

It's engineered to cool down a 600+hp engine in a cramped engine bay, it will be just fine for your Monte. I've used them with HUGE success. The shroud also has flaps in it to allow air to flow through at speed.

[70MC]

May be a silly question but the fans make sure they are moving air the right direction? Also if this is an antique copper/brass radiator consider that the core tubes aren't restricted the ends can look good but the tubes can still have corrosion in them. Another thing is coolant flow speed like is your water pump moving the coolant too fast to radiate heat while in the radiator?

Fans are moving air proper.
Yes, antique radiator. The ends of core look brand new, but could be clogged.
I have tried 3 pumps and 2 ratios, stock and 10% under, none made a differance.

[70MC]

copper conducts heat better than al
al is lighter
frontal area makes the biggest difference
#cores also
but also fin count
straight fins 16 fins per inch works great
however something does not compute
fans do not really help above 35 mph
is your core support sealed- all the holes
running a spoiler under the core support?
first follow up on the fans running backward
572 cu inches is not really relevant just cruising down the highway
in only takes so much HP to move a 70 Chevelle down the highway big block or small block
now road racing or towing would be a different problem
BTW work up on your heat transfer knowledge- lots of bs from the radiator mfg out there YOU have to understand

The reason i think it is related to the larger engine is i had no problem cooling my 420 or 434 in any weather. With the small blocks, if it was 40 out the fans might not ever turn on. When it is 40 out with the 572 the never turn off when 40.
The 572 has a 160 t-stat, timing locked at 34 with adjustable vac. advance set at 10 degres and hooked up.

[lefty o]

it is sort of related to the larger engine, but the engine just showed you a deficiency. more horsepower=more heat, and now youve exceeded what your current equipment can handle.

[user-612937456]

May be a silly question but the fans make sure they are moving air the right direction? Also if this is an antique copper/brass radiator consider that the core tubes aren't restricted the ends can look good but the tubes can still have corrosion in them. Another thing is coolant flow speed like is your water pump moving the coolant too fast to radiate heat while in the radiator?

Fans are moving air proper.
Yes, antique radiator. The ends of core look brand new, but could be clogged.
I have tried 3 pumps and 2 ratios, stock and 10% under, none made a difference.

Are you running a thermostat? If not you need a restricter disk to slow down the coolant
Anyway it sounds like you have either an airflow restriction or a coolant flow problem if it cools sitting still but overheat at 35 MPH

[peejay]

it is sort of related to the larger engine, but the engine just showed you a deficiency. more horsepower=more heat, and now youve exceeded what your current equipment can handle.

Or less airflow through the engine bay due to the larger engine.

What does it have for an airdam under the core support? I had one car that had highway coolant temps go from 175 to 235 after taking that off. Put it RIGHT back on again! The airdam forces air to go through the radiator and also makes a low pressure area behind the radiator to pull it through the other side. Airflow might have been good enough with a smallblock but the bigblock might be increasing underhood air pressure enough that the air doesn't want to flow through the radiator anymore.

[70MC]

it is sort of related to the larger engine, but the engine just showed you a deficiency. more horsepower=more heat, and now youve exceeded what your current equipment can handle.

Or less airflow through the engine bay due to the larger engine.

What does it have for an airdam under the core support? I had one car that had highway coolant temps go from 175 to 235 after taking that off. Put it RIGHT back on again! The airdam forces air to go through the radiator and also makes a low pressure area behind the radiator to pull it through the other side. Airflow might have been good enough with a smallblock but the bigblock might be increasing underhood air pressure enough that the air doesn't want to flow through the radiator anymore.

That is somthing to consider for sure. This car never came with one so i will need to scavenge or make one.

[70MC]

I can say for sure, is this engine produces more heat than my small blocks.
I have a test stand with a much smaller radiator and electric fan.when i started it on the stand, It got up to temp in no time and got to 200 faster than the sbc. Same in the car, it warmes up fast.
I dont think there is anything wrong with the engine.

[Kevin Johnson]

it is sort of related to the larger engine, but the engine just showed you a deficiency. more horsepower=more heat, and now youve exceeded what your current equipment can handle.

Or less airflow through the engine bay due to the larger engine.

What does it have for an airdam under the core support? I had one car that had highway coolant temps go from 175 to 235 after taking that off. Put it RIGHT back on again! The airdam forces air to go through the radiator and also makes a low pressure area behind the radiator to pull it through the other side. Airflow might have been good enough with a smallblock but the bigblock might be increasing underhood air pressure enough that the air doesn't want to flow through the radiator anymore.

That is somthing to consider for sure. This car never came with one so i will need to scavenge or make one.

http://www.firstgenmc.com/forums/index. ... ntry100066

037.jpg

~~~~~~~~~~~~~~~~~~~~~~

http://www.spoilersbyrandy.com/Pages/70 ... oiler.aspx

[70MC]

Thank you for finding that Kevin.