68 Barracuda 440 getting hot in traffic

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a totally untrue generalization. Some are, some aren’t. Depends entirely on what you’re comparing.

And he already has a 26” radiator, no ones even asked if it’s stock or aftermarket yet.

Glad you guys solved the problem he didn’t have already though.

Are you suggesting the OP to overdrive the fan? A Stock 26” is not possible on a 68 to my knowledge. Please enlighten us.
 
Guys, it's not a stock radiator..the car was restored in 2006.
As far as the car actually boiling over it didn't but the longer I sat there the more the temp creeped up until I shut it down.
I bought the car and didn't get enough info on the engine build.
It definitely has a decent cam in it but I dont know the specs.
When I bring it back tomorrow from the car show I'll let it sit while running and actually see how hot it gets with a temp gun... didn't want to do that at the car show with all the chevys around!

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I'll send better pics tomorrow when I get it home of the actual radiator and shroud set up .

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You can put a electric fan out front on a thermostat that only comes on at 200 if you want use it like a pusher fan when your in traffic lugging around.
 
Guys, it's not a stock radiator..the car was restored in 2006.
As far as the car actually boiling over it didn't but the longer I sat there the more the temp creeped up until I shut it down.
I bought the car and didn't get enough info on the engine build.
It definitely has a decent cam in it but I dont know the specs.
When I bring it back tomorrow from the car show I'll let it sit while running and actually see how hot it gets with a temp gun... didn't want to do that at the car show with all the chevys around!

View attachment 1715454336

View attachment 1715454337
Car is kick a$$ !!^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
For those that say you cant put a bigger rad. in it , I`ve got a 28x19 crossflow in mine , and "haven`t cut the cradle out for the tanks either" , the orig. core opening is the same width as my core. Using a 17" , 6 blade, 2'' pitch fan , with a 2954 clutch set up . My temps are about like yours , hasn`t gone over 212 w/ this set up , Of course mine is more likely built a little hotter and creates more heat , and the 68 barracuda has a small engine bay , especially with raised port heads.
I may go to an 18" fan if a problem pops up next summer , I do have room to trim my custom made shroud a little for it . I pretty much agree w/ what 72bluanndblu and RRR said , I do have a 14'' elec. fan that is set to come on at 200* in front of the rad. too , its comforting to see/hear it kick on at a stop light in the summer , but might be actually blocking a little air flow on the hi way, but hasn`t been a problem--------.
I have a 1 to 1 pulley ratio , and haven`t found a bigger water pump pulley to speed it up ,and not sure if theres enough room to run a bigger on w/o hitting the crank pulley anyway
 
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Check your ignition timing. Maybe a couple more degrees of timing at idle will help keep it cool. What do your plugs look like? Do you have a wide band? A lot of cooling problems are actually engine tuning problems. Have you had the radiator rodded out? Even if it looks nice it could've just been a spray can resto. If you want a solve a problem you have to stop making assumptions and go verify everything yourself.
 
Measure the pulleys. You need to overdrive the water pump.

Just because it has "stock" pulleys doesn't mean it's the correct pulleys.
 
A 26” core does nothing when a 22” opening is all you have. Stay tuned. The OP has gotten what he asked for!

BS. I'll post a picture of exactly how little of the 26" radiator is "covered" by the 22" radiator shroud. It has little to no effect on the cooling abilities of the 26" radiator.

And, that's only if the fan isn't running. If the fan shroud covers the whole radiator, the fan pulls air across the whole radiator. That's why the shroud is there.

Are you suggesting the OP to overdrive the fan? A Stock 26” is not possible on a 68 to my knowledge. Please enlighten us.

No, I am not suggesting the OP overdrive the fan. I'm suggesting he find out if he's underdriving the fan, and whether or not he has the correct water pump for the pulley set up he has. If he has a mismatch of stock pulleys, he may not have the drive ratio he's supposed to.

I have no idea if a 26" radiator was available stock in '68, I don't believe they were. That said, yes, a stock 26" radiator will fit in his '68. 26" radiators were available in all of the later A/C cars, the radiator support is the same except for the opening. And the opening isn't that different.

You can put a electric fan out front on a thermostat that only comes on at 200 if you want use it like a pusher fan when your in traffic lugging around.

Hanging a pusher fan out if front just slows airflow the rest of the time. A properly tuned mechanical fan system should work just fine for the OP. If you want an electric fan, the mechanical should be dropped entirely and replaced with an electric to handle all the cooling duties. Running both is just inefficient.

Guys, it's not a stock radiator..the car was restored in 2006.
As far as the car actually boiling over it didn't but the longer I sat there the more the temp creeped up until I shut it down.
I bought the car and didn't get enough info on the engine build.
It definitely has a decent cam in it but I dont know the specs.
When I bring it back tomorrow from the car show I'll let it sit while running and actually see how hot it gets with a temp gun... didn't want to do that at the car show with all the chevys around!

View attachment 1715454336

View attachment 1715454337

That is a great looking car! :thumbsup: I love notch's!

Yes, I would suggest confirming your temp gauge readings are accurate, the little aftermarket gauges can be misleading. My autometer temp gauge reads like 10°F high at 200°. Pictures of the rest of the radiator and shroud set up will help, it doesn't look like you have a stock shroud on there. Also, a picture showing where the fan sits in the shroud would be helpful, as they have to be in the right spot too.

Measure the pulleys. You need to overdrive the water pump.

Just because it has "stock" pulleys doesn't mean it's the correct pulleys.

He doesn't need to overdrive the fan. He just needs to make sure he has the right pulley ratio.
 
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Here are some measurements and pictures of the 22" radiator support with a 26" radiator behind it. Let me first say that if this was even an issue, the loss of cooling efficiency would be at speed. That's when the airflow through the radiator support would have the largest effect. At idle, the fan is moving all the air. If the fan shroud covers the entire radiator, and the core is not directly in contact with something in front of the radiator, then the fan will still pull air across the entire core.

So, here's the opening on a 22" radiator support. Mine actually measures 22 3/4", so right off the bat there's only about 1 5/8" of core on each side of the opening.
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This is what you're "losing", a 26" radiator support would be open back to the red dotted line (in line with the lower reinforcement)
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But you can see from the top that while the radiator support opening is smaller than the core, the core is still surrounded by air. The support does not come in contact with the core, so air still circulates through it
IMG_7832.jpeg

A picture from the side showing the air gap. There's a good 1/2" or more. You can even see some little piece of leaf back there in the corner, wouldn't have blown back in there if there wasn't airflow right?
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Bottom line is you still get more cooling out of a 26" wide core assuming everything else is equal. Yes, at speed you will have better airflow across the middle 22 3/4" than the 1 5/8" down each side, you lose some air speed on the edges and therefore a little efficiency. But if your car isn't cooling at speed that little bit on the outside isn't going to save you, something else is wrong. At idle the fan will pull air across that entire core as long as the fan shroud covers the whole radiator. The fan is pulling air at a much slower speed, and a 1/2" air gap is plenty to pull air around that lip and through the outer edges of the core. The back side of the radiator isn't obstructed at all compared to a smaller 22" core. And even if the outer tubes are slightly less efficient, they're basically bonus compared to a 22". It's all extra cooling that a 22" can't provide because it's not there. Not to mention the increased volume of coolant from the larger tanks and additional tubes.

Regardless, the OP has a 26" radiator already. Buying a 22" would still be a downgrade, and cutting the radiator support isn't necessary at all if the car is cooling at speed.
 
BS. I'll post a picture of exactly how little of the 26" radiator is "covered" by the 22" radiator shroud. It has little to no effect on the cooling abilities of the 26" radiator.

And, that's only if the fan isn't running. If the fan shroud covers the whole radiator, the fan pulls air across the whole radiator. That's why the shroud is there.



No, I am not suggesting the OP overdrive the fan. I'm suggesting he find out if he's underdriving the fan, and whether or not he has the correct water pump for the pulley set up he has. If he has a mismatch of stock pulleys, he may not have the drive ratio he's supposed to.

I have no idea if a 26" radiator was available stock in '68, I don't believe they were. That said, yes, a stock 26" radiator will fit in his '68. 26" radiators were available in all of the later A/C cars, the radiator support is the same except for the opening. And the opening isn't that different.



Hanging a pusher fan out if front just slows airflow the rest of the time. A properly tuned mechanical fan system should work just fine for the OP. If you want an electric fan, the mechanical should be dropped entirely and replaced with an electric to handle all the cooling duties. Running both is just inefficient.



That is a great looking car! :thumbsup: I love notch's!

Yes, I would suggest confirming your temp gauge readings are accurate, the little aftermarket gauges can be misleading. My autometer temp gauge reads like 10°F high at 200°. Pictures of the rest of the radiator and shroud set up will help, it doesn't look like you have a stock shroud on there. Also, a picture showing where the fan sits in the shroud would be helpful, as they have to be in the right spot too.



He doesn't need to overdrive the fan. He just needs to make sure he has the right pulley ratio.



Why not overdrive the pump? Almost every factory pump was over driven. Flow is everything.

Overdrive the pump.
 
Why not overdrive the pump? Almost every factory pump was over driven. Flow is everything.

Overdrive the pump.
Agree , but finding a pulley w/ the right depth that's bigger than the stock single belt (almost 7'') ones hasn't happened for me , been looking a little tho

Y Rose and blu72 , do u think opening up my cradle to un cover the side tanks would have much benefit ?----------28x19 crossflow--
 
Car is kick a$$ !!^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
For those that say you cant put a bigger rad. in it , I`ve got a 28x19 crossflow in mine , and "haven`t cut the cradle out for the tanks either" , the orig. core opening is the same width as my core. Using a 17" , 6 blade, 2'' pitch fan , with a 2954 clutch set up . My temps are about like yours , hasn`t gone over 212 w/ this set up , Of course mine is more likely built a little hotter and creates more heat , and the 68 barracuda has a small engine bay , especially with raised port heads.
I may go to an 18" fan if a problem pops up next summer , I do have room to trim my custom made shroud a little for it . I pretty much agree w/ what 72bluanndblu and RRR said , I do have a 14'' elec. fan that is set to come on at 200* in front of the rad. too , its comforting to see/hear it kick on at a stop light in the summer , but might be actually blocking a little air flow on the hi way, but hasn`t been a problem--------.
I have a 1 to 1 pulley ratio , and haven`t found a bigger water pump pulley to speed it up ,and not sure if theres enough room to run a bigger on w/o hitting the crank pulley anyway
Famous bob- you want a smaller water pump pulley to go faster not a bigger. -Jed.
 
Very Nice ride!

Anything can be made to fit and work. That said, is it worth it in the long run and right for your car? Think twice and cut once as it can effect many things. These do not grow on trees and once cut is harder to put back. I know this matters to few anymore but to some it does! I ran an oversized radiator for many years and it never panned out.

I resisted the cutting and glad today I did. Find an 033 in new shape and run all the standard BB equipment no exceptions and you will be happy. A little creep is really not an issue! JMO!
 
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Why not overdrive the pump? Almost every factory pump was over driven. Flow is everything.

Overdrive the pump.

Nope. Only factory AC cars were overdriven. Everything else was .95:1. So most factory cars were slightly under driven because “most” of them weren’t AC cars. The ratio’s are in the FSM excerpt I posted on the first page.

We don’t even know his current pulley diameters anyway, so we don’t know if he’s already overdriving the pump or not.

The cooling system isn’t just one part, it’s everything working together. Look at the factory set ups, the overdriven pulley set (1.4:1) on the AC cars ran a water pump with fewer blades (6). The .95:1 pulley set up ran an 8 bladed pump. Just spinning the impeller faster isn’t necessarily better if it wasn’t designed for optimal flow at that speed. Why did the factory reduce the number of blades on the water pump for the cars with the overdriven pulleys?

Air flow is more likely to be his issue anyway with his symptoms. Yes, over driving the pump overdrives the fan too. But the fan blades are also optimized for a specific rpm range, just upping the rpms on the fan does not absolutely guarantee it’ll move more air.

You want the fan and pump spinning at the rpms they were designed for. Arbitrarily overdriving either because you can’t figure out what’s actually wrong isn’t a good solution. Plus, overdriving the fan and pump will steal more horsepower to drive them.

Very Nice ride!

Anything can be made to fit and work. That said, is it worth it in the long run and right for your car? Think twice and cut once as it can effect many things. These do not grow on trees and once cut is harder to put back. I know this matters to few anymore but to some it does! I ran an oversized radiator for many years and it never panned out.

I resisted the cutting and glad today I did. Find an 033 in new shape and run all the standard BB equipment no exceptions and you will be happy. A little creep is really not an issue! JMO!

There’s no need for the OP to cut anything, already covered that. Just because you couldn’t figure it out doesn’t mean it won’t work.

And a larger radiator is only one part of the cooling system. A big radiator won’t solve every cooling problem, everything has to work together. The OP’s system is working well everywhere but idle. That points more to an airflow problem, not a radiator issue.

The OP’s fan shroud has large gaps, and all the air pulled around the shroud and through those gaps is air that’s not going through the core.
 
You can put a electric fan out front on a thermostat that only comes on at 200 if you want use it like a pusher fan when your in traffic lugging around.

careful doing this as it impedes air flow through the radiator and can lead to other issues.

I prefer twin electric pullers over all other setups, especially on a BB Abody because the distance between the pump snout and the radiator is limited. With twin electrics the pump snout and pulley fit in between the fans and you can't beat the CFM flow at idle you get with electric fans as well as the ability to run them after the car is shut off.
 
careful doing this as it impedes air flow through the radiator and can lead to other issues.

I prefer twin electric pullers over all other setups, especially on a BB Abody because the distance between the pump snout and the radiator is limited. With twin electrics the pump snout and pulley fit in between the fans and you can't beat the CFM flow at idle you get with electric fans as well as the ability to run them after the car is shut off.

That being said , two 14" elec pullers wouldn`t keep mine cool --------------------
 
Anyway you shake the dice, it takes air flow to keep them cool, you either have to fab a good shroud or get the electric fans for when your in slow traffic.
 
That being said , two 14" elec pullers wouldn`t keep mine cool --------------------

If they're not pulling at least 3,000 cfm they're not gonna cut it. Guys buy fancy, expensive electric fans all the time without knowing what they actually flow. Just like a mechanical fan the electric fans benefit from a good shroud, which many aftermarket electric fans don't come with but are often part of how they're rated at their maximum cfm. The Ford Contour fans I use are rated at 3,500+ cfm on the low speed and over 5,000 cfm on the high speed. They come with a built in shroud that was designed for them. Just buying an expensive aftermarket electric fan doesn't guarantee anything, some are only capable of 1,000 cfm. Even two of those won't even begin to work as a standalone replacement for a mechanical fan.
 
I have Contour fans wired for full-speed only, and when they kick on the temp gauge starts dropping quickly. It remains to be seen if I have enough radiator for a hot summer day but it does great in 60 deg weather :)

I did note that if the fans are turned off, the blades and the shroud does demonstrate some restriction (temps slowly climb even at a steady 30 mph cruise). It doesn't have "flaps" that can be opened by the incoming airstream.
 
I have Contour fans wired for full-speed only, and when they kick on the temp gauge starts dropping quickly. It remains to be seen if I have enough radiator for a hot summer day but it does great in 60 deg weather :)

I did note that if the fans are turned off, the blades and the shroud does demonstrate some restriction (temps slowly climb even at a steady 30 mph cruise). It doesn't have "flaps" that can be opened by the incoming airstream.

Interesting! What does the rest of your cooling system look like- radiator, water pump, thermostat?

My car runs right at the thermostat temp (180) if I’m doing 30 or more and it’s under 90 degrees out. Never had an issue with the temp climbing if I’m moving at speed unless it’s pretty hot out. My fans pretty much only run if I’m stopped or stuck in traffic. And wired with both speeds I run almost exclusively on the low speed. I’ve only had the high speed kick on when it was 105 or better and I was in the city catching all the lights.
 
Interesting! What does the rest of your cooling system look like- radiator, water pump, thermostat?

My car runs right at the thermostat temp (180) if I’m doing 30 or more and it’s under 90 degrees out. Never had an issue with the temp climbing if I’m moving at speed unless it’s pretty hot out. My fans pretty much only run if I’m stopped or stuck in traffic. And wired with both speeds I run almost exclusively on the low speed. I’ve only had the high speed kick on when it was 105 or better and I was in the city catching all the lights.

Out of curiosity , what are the outside mounting dementions of contour fans ?
 
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