Brassworks heater core

Has anyone tried these BRASS heater cores. Seems like it’d be the way to go? Don’t need one yet, because t I’m sure that day is coming.
https://www.thebrassworks.net/search?q=Jeep+2004

I have read through countless threads on this forum about them and the general consensus is they do not put out much heat. They offer a newer version with more rows, but I do not know anyone that has taken the dive to find out if it's work it or not.
 
I have the old version and the heat is very very weak. High 90s to low 100’s at best with a fully warmed up engine. And this is on a 50 degree day, so not very cold out.


anyways, the other day I noticed the AC condenser condensation line leaking coolant, so it looks I will be doing this job again.

Call me stupid, but I may get another brass works as now they have a larger core, more find and more rows.

I have had 50 year old brass heater cores in classic cars without issue. I hoped this one would go longer than a year and 8000mi… 😬
 
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I have the old version and the heat is very very weak. High 90s to low 100’s at best with a fully warmed up engine. And this is on a 50 degree day, so not very cold out.


anyways, the other day I noticed the AC condenser condensation line leaking coolant, so it looks I will be doing this job again.

Call me stupid, but I may get another brass works as now they have a larger core, more find and more rows.

I have had 50 year old brass heater cores in classic cars without issue. I hoped this one would go longer than a year and 8000mi… 😬

I'm following closely. I picked up a rust fre fairly well preserved 2004 X on Sept 1. At first it was the little things; dirty interior, rough ride, oily looking engine, spark plug change, etc.. Within 5 weeks it was all control arms, panhard bars, front and rear shocks and springs, sway bar bushings, front main seal, rear main seal, oil pan gasket, oil pump, timing chain and gear, water pump, thermostat, thermostat housing, coolant temperature sensor, rusted coolant galley so a full cooling flush, valve cover gasket, radiator, all hoses, serpentine belt, harmonic balancer, motor mounts, transmission mount, SYE, front and rear drive shafts, brake calipers, brake rotors, brake hoses, seat cushion foam... and all interior carpet.

I've had the rear carpet pulled out for weeks now, and just last night I finally got around to installing the rear bedrug portion. I had a few minutes before bed so I pulled the front carpet out. Low and behold, there is a wet spot on the passenger foot well. Lucky me! At this point, the entire Jeep is going to be new. Like you, I'm not looking forward to the job, and I don't want to put cheap garbage in only to do the job again a short while later. I've been following the Brassworks argument, and I'm interested in what you find with the new model. I'd absolutely be willing to give up a slight amount of heat for peace of mind, but I don't think it would be worth a gentle warm breeze in place of actual heat.
 
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Thoughts on the redesigned BrassWorks core?

Ha! We're all wondering. I think the BrassWorks design is ignoring an important part, and that's flow rate. They go into detail about thermal efficiency, core capacity, etc, but honestly the most important thing is dwell time. They knock turbulators and claim they're not needed, which maybe they're not, but the effect of their use is longer dwell time of the coolant in the core. I think if they can slow the coolant flow through the core, it will allow the thermal efficiency to actually work. I don't care if the thing is made of diamond or silver, if the coolant isn't spending enough time in the core it won't be transferring the heat.

I'm currently thinking my leak is a clogged cowl drain, but the heater core is at the very top of the list nonetheless. I'm still liking the brassworks, but I wish there was less drama and just a touch more R&D to get it across the finish line.
 
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So maybe a restriction in the return line would help? An old ragtag vehicle I had years ago had the temp control valve on one of the heater lines to control temp. Just a thought.
 
So maybe a restriction in the return line would help? An old ragtag vehicle I had years ago had the temp control valve on one of the heater lines to control temp. Just a thought.

Exactly. Reducing flow will increase time allowed for air to extract the heat energy. It's a commonly used technique in engine radiators. It's probably the case that the flow rate is simply not being accounted for by BrassWorks. Not saying they don't know what they're doing, but I think they're just designing their replacement to fit the offset hoses and container of the TJ using their standard construction techniques. I'd like to hear if an in-line flow restrictor works with the existing BrassWorks units that people have complained about.
I think the restrictor should probably go on the feed side, as it won't reduce the temperature of the incoming coolant, but it will reduce the flow rate through the core. I think a restrictor after the core will increase pressure in the core.

There is an OEM part for 96-04 Mustang that may work. Maybe start here for a cheap option.

http://gojeep.willyshotrod.com/HowtoRadiatorRestrictor.htm
 
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Exactly. Reducing flow will increase time allowed for air to extract the heat energy. It's a commonly used technique in engine radiators. It's probably the case that the flow rate is simply not being accounted for by BrassWorks. Not saying they don't know what they're doing, but I think they're just designing their replacement to fit the offset hoses and container of the TJ using their standard construction techniques. I'd like to hear if an in-line flow restrictor works with the existing BrassWorks units that people have complained about.
I think the restrictor should probably go on the feed side, as it won't reduce the temperature of the incoming coolant, but it will reduce the flow rate through the core. I think a restrictor after the core will increase pressure in the core.

There is an OEM part for 96-04 Mustang that may work. Maybe start here for a cheap option.

http://gojeep.willyshotrod.com/HowtoRadiatorRestrictor.htm

https://lmr.com/item/LRS-18599A/79-04-Mustang-Heater-Core-Flow-Restrictor

Is this the Mustang part?
 
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So maybe a restriction in the return line would help? An old ragtag vehicle I had years ago had the temp control valve on one of the heater lines to control temp. Just a thought.

No, it's nonsense.

"dwell time" isn't a thing, except that it's the reciprocal to mass flow. If you cut the mass flow in half then yes, you double the temperature difference, but the overall amount of heat transferred hasn't increased, it's actually gotten worse.

If you slow down the water, you'll get cooler water coming out because you've transferred the heat into a smaller mass of fluid, you'll decrease the mean temperature difference which will reduce the total heat transfer and your air will come out even colder.

If you slow down the air, you'll get more temperature rise and hotter air at the outlet because you're transferred the heat into a smaller mass of air, but the air volume will be reduced; so you might still singe your toe hair but it may not keep up with the heat loss through the tub and top and the interior may never warm up.
 
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No, it's nonsense.

"dwell time" isn't a thing, except that it's the reciprocal to mass flow. If you cut the mass flow in half then yes, you double the temperature difference, but the overall amount of heat transferred hasn't increased, it's actually gotten worse.

If you slow down the water, you'll get cooler water coming out because you've transferred the heat into a smaller mass of fluid, you'll decrease the mean temperature difference which will reduce the total heat transfer and your air will come out even colder.

If you slow down the air, you'll get more temperature rise and hotter air at the outlet because you're transferred the heat into a smaller mass of air, but the air volume will be reduced; so you might still singe your toe hair but it may not keep up with the heat loss through the tub and top and the interior may never warm up.
I think a restrictor would work if the coolant flow was on/off via a thermostat, but I think the coolant flow is just continuous on the heater core. What in your estimation is the cause of the reduced output of the BrassWorks? They gladly list all of the technically superior specs, yet the units make less heat. Somewhere, the heat transfer is not occurring.
 
So what is the purpose of the turbulators they put in the coils? Exposes the coolant to the outside edge of the tubes? Slows the flow down? I’ve been in this discussion before on here and it’s still not clear in my head how slowing the flow doesn’t increase the temp exchange.
In my beer making days I was able to remove more heat from the wort by slowing the flow through the tubes. Engineering I’m no good at understanding, but experience tells me different.
 
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