1970 26" BB radiator fit in a 1974 Barracuda?

[440_man]

I have a 1974 Cuda that was originally a 318 car, which now has a 440 installed in it. I have fought with slight overheating problem at idle for years, and now would like to buy an aluminum radiator to put an end once and for all to my overheating problems.

Since the car was originally a 318 car, the radiator opening is 22". The radiator came out of a 1970 Chrysler 300 (the 440 donor car). The 440 motor, being a 1970, has the lower water pump port on the driver's side. I am looking at buying a 26" aluminum 2 core radiator with 1.25" core size for a 1970 - 72 BB which comes with a lower radiator hose on the driver's side.

I realize that putting a 26" radiator into a 22" hole is not ideal, but the car is painted already, so I do not want to convert the passenger side radiator mount to make the hole bigger.

My question is this: Do 70 - 74 e body cudas have the same radiator mounting? Put another way, If I purchase a 70-72 BB radiator, will the driver's side of the radiator mount up in the proper place on my 74 (originally 318) car? I realize that the passenger side of the radiator will need an adapter bracket or some spacers.

 

[pschlosser]

Shoe-horning a 26-inch radiator into a 22-inch opening is not ideal for two (or more) reasons.

1. the 22-inch opening blocks some of the airflow to the 26-inch radiator, making it less effective than it would with a full size opening.

2. cutting the sheet metal to expand the opening is fugly. even refitting the correct 26-inch sheet metal can still be observed by the discerning eye.

If you don't really care what it looks like, and want it functional, go ahead and cut the sheet metal wider and drill new mounting holes. From memory, it is the passenger-side sheet metal that varies with radiator width. I do not recommend cutting any of the driver-side sheet metal

Other options:

Upgrade to a four-core 22-inch radiator. These cool better than the OEM 22-inch three-core, and still look pretty much factory OEM.

Add a fan shroud, if missing.

Test and replace the clutch on the fan, if needs be. Seek out and use the correct 440 (7-blade) fan.

There are many 440-4 HP cars with 22-inch radiators.

I know it is summer, right now. But if your car is overheating frequently on the 22-incher, there may be one of the issues, above, you can resolve to make it cool better.

Lastly, under what conditions does it overheat? At idle? Going up long grades? For the most part, the 22-incher can keep the 440 HP cool, but not under extreme conditions.

Edit: Whoops, you DO say "at idle." okay, it's possible you have a correctable issue with cooling, thermostat, clutch fan, wrong fan, no shroud, etc.

 

[Chryco Psycho]

A C body rad is not a direct bolt in but it will add capacity can be made to fit & with a shroud can help a lot .

 

[Xcudame]

Any aluminum radiator (22" or 26") is better than the original brass radiator. Plus I guarantee the 53 year old Chrysler radiator is not 100% of it's original cooling capability. Probably 60% at best. Pschlosser is correct, only the right side yoke changes between the 22" and 26". And there's no sane reason to block off 4" of a 26" radiator.
IMO, get a 22" aluminum radiator, flush the coolant system, make sure your fan clutch is working properly and install an AC/HD water pump. And definitely run a fan shroud. If an automatic transmission, consider an auxiliary trans cooler to help both the engine and transmission.
Oh, and welcome to FEBO from the desert!

 

[440_man]

So a little more info here as to the overheating problem in case we can come to a resolution without buying a new aluminum radiator.

20 years ago, the radiator was brought to the local radiator shop to get checked out. Back then already, the shop said the original radiator was not up to the job anymore, so we used the original tanks, and turned it into a 4 core. Can't say how big the cores are.

We made a sheet metal shroud, and switched to a flex fan 6 blade. I forget the diameter. That helped my idle / slow traffic overheating somewhat, but if its over 90 deg F, the car would still creep up in temp and if stuck in traffic long enough, it would reach 230 deg. Going down the road at hiway speed, however, it would run about 170. My thermostat was a 160 degree good Stant.

I have an automatic transmission, and use the radiator tranny cooler in series with an external aftermarket cooler.

Fast forward to this past year...We took the motor out over the winter for a camshaft change, and ended up tearing it all the way down for a complete rebuild / freshening up with new bearings all the way around, as well as a valve job. Its nice to have a brother that owns a machine shop that specializes in engine machine work...

When torn down, the engine was put through the hot tank and power-washed throughout, so the blocks coolant system is clean.

We also took the radiator back to that same radiator shop, and they flushed it good and proper. I am running a 180 thermostat this time around, and it runs about 190 deg down the road, and creeps up when idling around town.

As I said in the original post, I have a high volume aluminum water pump installed as well.

So the variables I can see in this problem yet are the fan, fan clutch (none) home-made shroud (which fits very nice and is seal up good) and the
radiator itself just possibly being too small.

I have heard different opinions on fan and clutch. What combo of fan / clutch works for those of you that have mildly modified 440s?

Any ideas?

 

[440_man]

I am thinking I should go back to the 160 degree thermostat as well...

 

[pschlosser]

I am thinking I should go back to the 160 degree thermostat as well...

A 160 simply opens sooner than a 180. Presuming your radiator and fan can over cool the engine (this does not seem the case, at the moment) there may be little difference between the two if the engine continues to exceed both thermostat thresholds.

 

[Xcudame]

Keep in mind that the boiling point of a 50/50 mix of antifreeze and water at 15psi is 268°F. So 230°F idling for a stout 440 is not terrible. Especially when it cools down. when driving faster. Is the fan between an 1" and 1-1/2" from the radiator? That helps as well with cooling. You may be OK were you're at.

 

[Juan Veldez]

I have had a few friends say the adding Water Wetter to the cooling system helps keep the temp down. Could be a cheap fix.

 

[Katfish]

Put the 26 in, definitely will help.
I did this 15yrs ago, the difference in this 22 and 26 opening is not much different.
Add a couple rubber spacers on the passenger side and you're good to go.

https://postimages.org/][/url]

 

[Challenger RTA]

2 or 3 wrong don't make a right. Myself I would check that the thermostats you have by putting in hot water and there opening and closing completely. Or observe flow in radiator when warming up at idle with cap loose then off. Next check the pump impeller if it's loose on the shaft. If you don't mind 2 small holes as Katfish did do it with the 26". Barrow a radiator from someone to see if it fixes your problem. There have been a lot of 22" radiators installed with no problem.
You put lipstick on a pig it's still a pig. I'm not calling you car a pig it's just a statement.

 

[i_taz]

Maybe the Evan's coolant..? Just watched this the other day and Jay mentions @ 4:52 it's good to over
300 deg.

 

[Ricks72Chlgr440]

So a little more info here as to the overheating problem in case we can come to a resolution without buying a new aluminum radiator.

20 years ago, the radiator was brought to the local radiator shop to get checked out. Back then already, the shop said the original radiator was not up to the job anymore, so we used the original tanks, and turned it into a 4 core. Can't say how big the cores are.

We made a sheet metal shroud, and switched to a flex fan 6 blade. I forget the diameter. That helped my idle / slow traffic overheating somewhat, but if its over 90 deg F, the car would still creep up in temp and if stuck in traffic long enough, it would reach 230 deg. Going down the road at hiway speed, however, it would run about 170. My thermostat was a 160 degree good Stant.

I have an automatic transmission, and use the radiator tranny cooler in series with an external aftermarket cooler.

Fast forward to this past year...We took the motor out over the winter for a camshaft change, and ended up tearing it all the way down for a complete rebuild / freshening up with new bearings all the way around, as well as a valve job. Its nice to have a brother that owns a machine shop that specializes in engine machine work...

When torn down, the engine was put through the hot tank and power-washed throughout, so the blocks coolant system is clean.

We also took the radiator back to that same radiator shop, and they flushed it good and proper. I am running a 180 thermostat this time around, and it runs about 190 deg down the road, and creeps up when idling around town.

As I said in the original post, I have a high volume aluminum water pump installed as well.

So the variables I can see in this problem yet are the fan, fan clutch (none) home-made shroud (which fits very nice and is seal up good) and the
radiator itself just possibly being too small.

I have heard different opinions on fan and clutch. What combo of fan / clutch works for those of you that have mildly modified 440s?

Any ideas?

Pictures of your current radiator/shroud/fan would help. If you still have the flex fan that is a no-go. The OE style fan moves a ton of air, and when mated to the proper shroud worked very well. The fact that it starts getting hot at idle means you likely have minimal airflow through your radiator. Another thing to consider is your timing. Retarded timing can also put a load on your cooling system. Are you running vacuum advance on your distributor?

 

[NoCar340]

Are you using the right thermostat? Your cooling system was engineered to work with a particular thermostat design. It was so important that in some instances Chrysler put a decal in the engine bay to make sure the correct 'stat was used. This style isn't available through regular channels anymore.

The "Robertshaw" design shown, now called a "high-flow" unit, is what came new in every single Chrysler V8 built during the musclecar era. It was a part of the system design. They're still available NOS (break out the parts books!) and through EMP/Stewart Water Pumps (although NOS are cheaper). The orifice area is at least twice as large as the junk we sell at auto parts stores. If it doesn't look the like one on the decal, it's not the right one no matter what the supersession or parts person says.

I have a 10.5:1 iron-head W2 340 in a '69 Valiant with a factory-style 22" radiator, a stock water pump, clutch fan (no shroud) and an NOS Mopar 2808631 (180°) thermostat. The engine bay is more cramped (less airflow) than an E-body. It stays right at 180° even on days in the high 90s. Traffic, idle, racing? It doesn't matter, the needle doesn't move.

Don't underestimate what the right thermostat can do. Always try the right thermostat before wasting money on anything else.

 

[Xcudame]

I think people are misguided thinking a 160°F thermostat and flex fan or electric fans will make their engine run cooler. As several here have mentioned, the correct temperature thermostat, a clutch fan with matching shroud and proper radiator cap is the best bet to keeping the engine cool at idle and low speeds. Especially when the engine is pumping out more horsepower than when it left the factory.

 

[pschlosser]

a 160°F thermostat may actually help the engine produce more power. But if the cooling system cant cool the engine when using a 180°F thermostat, a 160 wont help it run cooler.

It seems only when the cooling system is efficient enough to over cool the engine, the thermostat plays a larger role

 

[440_man]

Are you using the right thermostat? Your cooling system was engineered to work with a particular thermostat design. It was so important that in some instances Chrysler put a decal in the engine bay to make sure the correct 'stat was used. This style isn't available through regular channels anymore.

View attachment 109770


The "Robertshaw" design shown, now called a "high-flow" unit, is what came new in every single Chrysler V8 built during the musclecar era. It was a part of the system design. They're still available NOS (break out the parts books!) and through EMP/Stewart Water Pumps (although NOS are cheaper). The orifice area is at least twice as large as the junk we sell at auto parts stores. If it doesn't look the like one on the decal, it's not the right one no matter what the supersession or parts person says.

I have a 10.5:1 iron-head W2 340 in a '69 Valiant with a factory-style 22" radiator, a stock water pump, clutch fan (no shroud) and an NOS Mopar 2808631 (180°) thermostat. The engine bay is more cramped (less airflow) than an E-body. It stays right at 180° even on days in the high 90s. Traffic, idle, racing? It doesn't matter, the needle doesn't move.

Don't underestimate what the right thermostat can do. Always try the right thermostat before wasting money on anything else.

The thermostat I installed this time around is a Stant 10231. Any idea if that is the correct style?

 

[440_man]

The thermostat I installed this time around is a Stant 10231. Any idea if that is the correct style?

My mistake - The cap is Stant 10231 16 PSI. Trying to find the paperwork on the thermostat yet to know exactly what brand of 180 deg it is.

 

[440_man]

The thermostat I installed this time around is a Stant 10231. Any idea if that is the correct style?

Are you using the right thermostat? Your cooling system was engineered to work with a particular thermostat design. It was so important that in some instances Chrysler put a decal in the engine bay to make sure the correct 'stat was used. This style isn't available through regular channels anymore.

View attachment 109770


The "Robertshaw" design shown, now called a "high-flow" unit, is what came new in every single Chrysler V8 built during the musclecar era. It was a part of the system design. They're still available NOS (break out the parts books!) and through EMP/Stewart Water Pumps (although NOS are cheaper). The orifice area is at least twice as large as the junk we sell at auto parts stores. If it doesn't look the like one on the decal, it's not the right one no matter what the supersession or parts person says.

I have a 10.5:1 iron-head W2 340 in a '69 Valiant with a factory-style 22" radiator, a stock water pump, clutch fan (no shroud) and an NOS Mopar 2808631 (180°) thermostat. The engine bay is more cramped (less airflow) than an E-body. It stays right at 180° even on days in the high 90s. Traffic, idle, racing? It doesn't matter, the needle doesn't move.

Don't underestimate what the right thermostat can do. Always try the right thermostat before wasting money on anything else.

Ok I found it - its a Napa THM 191 180 deg thermostat. I would say it does NOT look like the picture above. Where does one find the actual correct thermostat for the 440?

 

[MoparCarGuy]

Napa shows this Holley thermostat (Balkamp) part #4364 with Napa Part #: BK 8251007. Link: https://www.napaonline.com/en/p/BK_8251007
Looks like the originals.