Aluminum Radiators in 2024
- Thread starter Sweet_Johnny
- Start date
I forget what size the original nipple was but it wasn't what one would expect for a 3/8" nipple. Like I said I had to use a threaded reducer cause I didn't feel froggy enough to bore the neck out to the right size & tap. I'll suggest boring out the reducer for better flow. I know the OE rad nipples had better flow than any screw on one.
My solution for the overflow nipple was to use a 3/8" fitting with 1/8" NPT because it's compact.
I cut the threads off and probed the inside with a 5/16- 24 tap. I cut the end off the aluminum fitting and it also received 5/16- 24 threads.
The two were joined with thread sealant and the o-ring is just for looks. It fills a small gap that I found ugly.
The radiator has been installed, checked for leaks, and pushed at 2,800 rpm for MILES without going over 210°. It stays as low or lower than my previous radiator during normal driving but weather changes make an apples to apples comparison impossible at this time. I should note that my radiator is missing the inserts that direct airflow to it as opposed to under/ out the sides so the temps could likely be about 15° cooler with them.
I also upgraded the petcock but need to shorten the 1/4" line so it clears the frame.
So far I'm pleased with my budget minded purchase, time will tell me if it was a mistake.
I cut the threads off and probed the inside with a 5/16- 24 tap. I cut the end off the aluminum fitting and it also received 5/16- 24 threads.
The two were joined with thread sealant and the o-ring is just for looks. It fills a small gap that I found ugly.
The radiator has been installed, checked for leaks, and pushed at 2,800 rpm for MILES without going over 210°. It stays as low or lower than my previous radiator during normal driving but weather changes make an apples to apples comparison impossible at this time. I should note that my radiator is missing the inserts that direct airflow to it as opposed to under/ out the sides so the temps could likely be about 15° cooler with them.
I also upgraded the petcock but need to shorten the 1/4" line so it clears the frame.
So far I'm pleased with my budget minded purchase, time will tell me if it was a mistake.
Excellent research and follow through. I have been using a Spectra for over 20 years and have had no problems. But I only use distilled water mixed with anti-freeze. I also cringe at seeing brass in aluminum. That is because of my boating experience. In a conductive or corrosive environment, brass and aluminum are death to each other. I only use stainless steel fittings in aluminum. If you never see road salt, carry on.
do you run an anode because of this?i put one in this last radiator..
I do run anodes on boats and outboard motors. But they spend all summer in saltwater. They wear out very slowly even in that environment. I have never used an anode on a car radiator. I have never had any corrosion or other problems as long as I stick to the distilled water/coolant. I like plastic drain valves- they never leak- but you can't be rough on them.
Thank you sir, I sure milked it though didn't I? Great advice on using distilled water, stainless/plastic petcocks, or even an anode. You're absolutely correct about brass/aluminum or dissimilar metals in general: I don't think I've ever removed a brass prop without damaging it. Somehow I completely forgot that information, so thanks again for reminding me! I may (probably not) replace the brass petcock adapter bushing with stainless so they're not touching.
As I promised Sweet_Johnny during our DM conversation, I've ordered, received and installed this same Blackhorse radiator and am quite impressed so far.
I have been working on completing my A/C upgrade on my LS3/4L80e swapped '86 442, and as such replaced the OE condenser with a new parallel flow Spectra unit. I re-assembled everything and found that my OE rad was now leaking. It was showing signs of age anyway, so I decided to pull the trigger on this as well while I was already wrenching on stuff. My research took me to this thread which was a huge help.
Pretty happy with how this install went.
- The different 2" upper hose connection wasn't an issue as my 1.5" upper hose easily stretched to fit. Looks fine.
- The bottom 2" hose was perfect.
- mine also has the brass drain petcock (not pictured in the product listing), and wasn't installed with thread sealer, so I reinstalled with some thread tape. I'm not concerned about the dissimilar metals here.
- The 1/2-20 trans line connections worked great with the OE setup.
- The overflow nipple is indeed smaller than the 3/8" OE nipple, but my flexible hose easily clamps down to fit. No pressure here so no worries.
- I like my OE cap better than the rather thin metal cap that came with the new rad. Maybe I'll look for something better aftermarket, maybe splurge for a billet one?
- My major concern was fit as I wanted to keep the OE look at the top of the core support. I was very pleased that I could still use the OE rad isolators (top and bottom) and core support rad top mounting bracket without any modifications.
- ...and my custom electric cooling fan setup mounted right up without any changes needed.
My install is complete. I've filled the coolant and so far no leaks. I'm waiting on some warmer weather to fire it up and get it hot, but I may not be able to wait long....maybe later today ;-)
Thanks again to Sweet_Johnny for posting this great detailed information. Very helpful.
EDIT - I fired up the 442 today and got it hot. No leaks and cools like a champ. Stoked!
I have been working on completing my A/C upgrade on my LS3/4L80e swapped '86 442, and as such replaced the OE condenser with a new parallel flow Spectra unit. I re-assembled everything and found that my OE rad was now leaking. It was showing signs of age anyway, so I decided to pull the trigger on this as well while I was already wrenching on stuff. My research took me to this thread which was a huge help.
Pretty happy with how this install went.
- The different 2" upper hose connection wasn't an issue as my 1.5" upper hose easily stretched to fit. Looks fine.
- The bottom 2" hose was perfect.
- mine also has the brass drain petcock (not pictured in the product listing), and wasn't installed with thread sealer, so I reinstalled with some thread tape. I'm not concerned about the dissimilar metals here.
- The 1/2-20 trans line connections worked great with the OE setup.
- The overflow nipple is indeed smaller than the 3/8" OE nipple, but my flexible hose easily clamps down to fit. No pressure here so no worries.
- I like my OE cap better than the rather thin metal cap that came with the new rad. Maybe I'll look for something better aftermarket, maybe splurge for a billet one?
- My major concern was fit as I wanted to keep the OE look at the top of the core support. I was very pleased that I could still use the OE rad isolators (top and bottom) and core support rad top mounting bracket without any modifications.
- ...and my custom electric cooling fan setup mounted right up without any changes needed.
My install is complete. I've filled the coolant and so far no leaks. I'm waiting on some warmer weather to fire it up and get it hot, but I may not be able to wait long....maybe later today ;-)
Thanks again to Sweet_Johnny for posting this great detailed information. Very helpful.
EDIT - I fired up the 442 today and got it hot. No leaks and cools like a champ. Stoked!
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