Downflow VS Crossflow Radiators

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Richie

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Hi everybody:

I'm thinking of getting a crossflow radiator next year. I was told they're more efficient than the regular downflow type. Are they any better? I've looked and looked but I can't find any A-Bodies with any crossflows so maybe that is saying something.
 
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More efficient? Interesting....I'm no scientist but I would bet gravity downward flow is more efficient than gravity horizontal flow. I believe a horizontal flow requires the coolant to be "pushed" slightly, which would be less efficient. As for cooling the coolant, that is dependent on the radiator core, not the flow direction.
 
Okay well like I said I've been looking for days to find an A-Body with one in it and nothing so I'll skip on that one.
 
Its an effort to mount a crossflow in an A-Body and other folks have done it. I had one long before the inexpensive drop in Champion and Cold Case Radiators. You need to fabricate Ford or GM type mounts to make it work and as stated, you're not going to gain much if anything over readily available drop ins.
 
What makes a crossflow better is that it is usually bigger. In the case of your vehicle, to put a crossflow in the stock location would not gain any size. Therefore it would not be any better. If you wanted to shoehorn in a wider crossflow, then you'd have more volume and therefore better cooling. However, most owners don't want nor need to do that. The best way for an A body owner to get increased capacity is to increase the thickness of the core to add more volume. Mopars never had 4 row copper/brass units originally. So your upgrade would need to be (in ascending order of capacity) from a company like US Radiator with a 4 row copper brass unit or if you wanted to go aluminum, you want a 'big' 2 row radiator of dual 1" or 1 1/4" tubes for maximum capacity. Any other upgrade options would likely be a lateral move for you and therefore you'd be better off staying with the original 3 row (or restored version) that was in there to start with.
 
I measured the all-out space I had between the frame rails and from the bottom to the hood and which side the inlet came in on and the outlet went out of. I then went to the summit racing site and punched in all those dimensions.. I opted for the side tanks as they would not benefit being in the air window as much as fins would.. now the entire window opening in my a body is filled with radiator fins..
As far as mounting it just making two little stirrups and bolting them to the bottom of the radiator core support with little rubber grommets in them and then buying the Chevy style radiator cap that just bolts to the front of the radiator and to the top of your course support holder. I think they're like under 30 bucks in your choice of black or Chrome... I was pissed because I missed the sale and didn't pull the trigger on about $139 I think I ended up paying like $159... Never even close to a overheating problems since.. and that's a large two core with side tanks...
 
There are pluses & minuses. In terms of cooling ability, no difference for same core area. With high mileage, cross flow cores can get silt build up in the lower tubes, as the stuff 'settles' when the engine is switched off & left for a period of time. Much like the crapola that settles in the bottom of the oil pan.
With an upright rad, the exiting coolant from the engine is on the high pressure side. At high rpms, pressure can force coolant past the cap.

More here: www.stewartcomponents.com
 
The crossflow radiators look like crap in our MoPar’s.

Just being honest.
 
Hi everybody:

I'm thinking of getting a crossflow radiator next year. I was told they're more efficient than the regular downflow type. Are they any better? I've looked and looked but I can't find any A-Bodies with any crossflows so maybe that is saying something.

I have a 28x19 crossflow in my 68 fastback, but cant answer ur question , but am interested .
 
What makes a crossflow better is that it is usually bigger. In the case of your vehicle, to put a crossflow in the stock location would not gain any size. Therefore it would not be any better. If you wanted to shoehorn in a wider crossflow, then you'd have more volume and therefore better cooling. However, most owners don't want nor need to do that. The best way for an A body owner to get increased capacity is to increase the thickness of the core to add more volume. Mopars never had 4 row copper/brass units originally. So your upgrade would need to be (in ascending order of capacity) from a company like US Radiator with a 4 row copper brass unit or if you wanted to go aluminum, you want a 'big' 2 row radiator of dual 1" or 1 1/4" tubes for maximum capacity. Any other upgrade options would likely be a lateral move for you and therefore you'd be better off staying with the original 3 row (or restored version) that was in there to start with.

big block A body cars dont have room for thicker radiators !
 
The big move to crossflow radiators has more to do with the height of front ends on modern cars when they tried to improve aerodynamics
 
I have a cheap jegs 2 pass cross flow with a high flow water pump with a diffuser plate built into it,run a 180 deg stat,a pusher fan behind the grill,never hit 200 degs in 105 degree weather,thats with 440 and 6-71 dyers blower, that radiator and try y headers were the best mods done in my 33yrs of abuseing this car,
 
My understanding is that a crossflow radiator causes the coolant to take more time to reach the bottom, therefore exposing it to more time in the airflow of the cooling fins.

The design of the crossflow on my Dakota perplexes me because the outlet is almost 1/2 way up the core, causing quite a bit of water to remain in the radiator when draining it to do work.

Why?
 
My understanding is that a crossflow radiator causes the coolant to take more time to reach the bottom, therefore exposing it to more time in the airflow of the cooling fins.

The design of the crossflow on my Dakota perplexes me because the outlet is almost 1/2 way up the core, causing quite a bit of water to remain in the radiator when draining it to do work.

Why?

...and if that's true, that means it's also slowing the coolant down getting out of the engine, which you do not want. Best case is get the coolant out as quickly as possible so it doesn't have time to heat up. So it sounds like the cross flow isn't conducive in doing that. ........if that's true.
 
before i switched to the cross flow i had a decent size down flow alum radiator,on a 100 deg day i could hit 215-220 and boil my brake fluid,watch a bug land on my hood at a traffic light then curl up and die from the heat, This mod worked great for my 68 gts convert,your results may differ,
 
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