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Advice on radiator and fan for LS3 swap

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While searching around for fans to cool the LS3 swap I came across two good possibilities.


C7 Corvette 600w fan with integrated pwm controller

2008 Ford Fusion fan and pwm controller


Could not find the exact size/dimensions of these fans so noted the radiator dimensions.  Also got to thinking of just swapping the compete Rad/fan setup from either of these cars.

C7 Corvette is 17.25x18.5x1

Fusion 17x25.75x1

These are single core radiators!  Is it advisable to use a single core in the S30 chassis?  Always thought the more cores the better in radiators.  How times have changed!


CX Racing has a nice 3 core 18.5x25x2.5 for under $200 made for the S30 chassis which very similar in size to the Fusion radiator so it's fan should fit well.


Edited by jsulse
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10 hours ago, jsulse said:

These are single core radiators!  Is it advisable to use a single core in the S30 chassis?  Always thought the more cores the better in radiators.  How times have changed!


Actually, pretty much all modern cars use single core radiators. In most case a single core radiator is going to be better if you are using a electric fan. With a single core radiator a electric fan can more easily draw air through the radiator. Single core radiator also have wider tubes, usually 1"-1.25". The wider tubes provide more surface area which results in better heat transfer and better cooling. People like to fall into the "Bigger is better" mentality and go with bigger radiators. Not only do they weigh more but for every row you add on a radiator the tubes get narrower. Also, one the cooling air has gone past the first row in a radiator, it doesn't draw as much heat from the additional rows. Let's look at what Champion Radiators offers for my 78 280Z... they have a 2 row core and a 3 row core radiator. No single row unfortunately. Anyway, on the 2 row core they claim "cools up to 400hp!". On the 3 row core they say "cools up to 650hp!!". If you look though, the 2 row cores have .75" thick tubes vs the .63" tubes in the 3 row. Now remember, both of the tube widths are much smaller than what would be in a single core radiator. Anyhow though, looking at the two radiators offered by Champion, I would think the 2 row would cool better than the 3 row using a electric fan. This all information based on using a electric fan with a aluminum radiator. Hope that helps


As far as radiators go, if the dimensions are correct that C7 radiator should fit in your car. The 280Z's have a bit more room but I'm not sure what Z you've got. I would definitely go with the complete C7 radiator and fan setup if I were you. Plus that way you can plug your fans right into your fuel injection harness and be good to go! I really wanted to use my single core radiator out of my 94 Z28 with my LT1 swap but it is way too wide and tall to fit. So I ended up going with a Champion 2 Row because everybody seems to be running Champion and they bolt right in. Hopefully it will work out well. I'm going to bolt my Z28 fans and fan shroud onto it since they will fit

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Thanks Wildfire490.


My car is a 1975. 


Your comments are exactly what I have been reading about radiators.  Chinese radiators like Champion use smaller .626-.75" cores while American made typically use the larger cores.  Most C6 and C7 Corvette "upgrade" radiators are two core using 1" or larger cores and the density of cores is higher.


What special connections should LS radiators have installed?  I believe a nipple for head steam hose.  Anything else?

Any recommendations on where upper and lower hose locations should be located on the radiator for a N/A motor,  seems there are few configurations from which to choose.  Sorry for the basic questions, my first LS swap.  Off to study OEM LS cooling system design...


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1 hour ago, mrk3cobra said:

I would not buy the Champion kit that includes  the radiator and 2 electric fans for a 240Z. The fans that come in the kit are not strong enough to pull air through a 2 core radiator. The radiator fits the 240Z perfect with an LS2. I needed to upgrade one of the fans to pull more air.


I hope that my fans from the Z28 are strong enough to pull air through the 2 row Champion radiator!!

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  • 4 weeks later...

I think it all boils down to money. How much are you willing to spend to do it right and have the peace of mind your car will not overheat and damage your engine. You can piece together components from different cars and make it work or you can call radiator builders that have engineers on their staff that will design a radiator for your specific set up. They take all you accessories into account, thickness of the condenser,  hp the car will be producing as well as how you will drive the car and design a radiator for you that will bolt right into the factory location and will cool your engine under any condition. Some people have super expensive turbo or stroker motors and want to cool it down with a $200 radiator but that's their choice. 


 My A/C blows super cold in 100 plus degree weather with the car sitting still. Here are some pictures of it, it was designed by Wizard Cooling. Highly recommend them if you decide to go that route. Here are a couple of pictures, before and after install.



Radiator 1.JPG

Cold Air Intake-2.JPG

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That's a beautiful engine bay!

I have a modest budget so need to "value engineer" a few things.  I get what you are saying about sizing the system properly.  The two fans I listed move massive amounts of air and are OEM durable.  Just need to spec a quality radiator with 1" cores.  Will post what I eventually get in my build thread. 

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  • 3 weeks later...

I have not purchased a fan or radiator yet.  Will most likely go with the C7 fan because if the integrated PWM unit and 600 watt power, it's truly a beast of a fan.  As for radiator that's still undecided.  As I get close to installing will search out a good radiator to match with fan.

Good luck with your build DonH

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  • 1 month later...

Here’s what I ended up getting :

EBay dual pass cross flow with large 1” tubes (most are much smaller!) was advertised as a 24” wide setup.


and a C7 fan from rock auto - took a little trimming to make the C7 fan fit my radiator core but only about 15 minutes worth! 


total in hard parts - $350!!! 




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Also - the C7 fan is a BEAST of a unit. I selected it because I wanted to have PWM capabilities for my setup. Terminator X ECU will be controlling the modulation. Will also be able to kick on higher for my AC system .


also - ITS A BRUSHLESS SPAL fan for $200 - you cannot beat it 

Edited by DonH
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On 8/29/2020 at 6:59 PM, 280Z-LS3 said:

Sweet setup, don't think you will have cooling issues!!!

I have been busy with chassis work and expect the fan/radiator purchase and install will be in a few months off.

Can you post a link to the radiator you purchased?

Thanks for posting.


Absolutely sir - Sadly hindsight being 20/20 I didnt pay attention to the outlet sizes on the dang radiator 😕  Ill need reducers now... 




You may be able to get the 26" size RAD to fit as on each side there is roughly 1/2" of space but could be really tight to the frame rails. it seems the core will do just fine considering the beastly fan! Ive found a radiator is ONLY as good as its fan... Im also going to have  aAC condenser in front of the RAD so the extra pull will be nice. 


The bonus is the petcock... One less thing I need to worry about adding to the universal style units out there. 



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  • 2 weeks later...
On 9/9/2020 at 11:30 AM, Mike Mileski said:

DonH, where did you find information that the C7 fan is actually a brushless Spal motor?


Mike Mileski

Tucson, AZ

A gentleman on Instagram / Holley Forum - "Projectgattago" is his screen name and IG handle. Was either going to use a fusion fan OR a C7 fan - the C7 fan has a "spal" logo on the back - needs to be the AC delco part. Yes its brushless - the key here is its from a 2014 to 2017 C7 Z06 OR Grand Sport. They came wiht this upgraded fan and wholly shit does it  move air! 

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