Hi, so I own a 1973 240z with an l28 in it. I had a question as I I'll be changing the radiator soon. From my understanding a 280z radiator should fit generally alright in a 240z, and I am most likely going to get an aluminum radiator off ebay, as most seem to be ok. I would recore, but I am trying to shed some weight off the car. My question is that what will be better, a 280z 2-core, or 240z 3-core. I would get a 240z 2-core but those seem to not be for sale anymore. I was thinking of a 280z 2-core since I heard some people had trouble getting air through the 3-cores, and 280z 2-cores are available. I would highly prefer not to use an aftermarket fan. My other choice would be a nos 240z radiator/ Any opinions? Thanks for reading and any advice given!

Hi Yoshi, On my '73 2 core radiator the side mounts were coming undone so I thought that instead of having them re-soldered I would get a 3 core radiator from MSA. (The old radiator was 34 years old at the time and somewhat funky-looking on the inside.) It works just fine with plenty of airflow. I have an L28 with an N42 10.5-1 compression head, a stage 2 cam, and a header and the operating temps are normal usually in the center of the guage. I have had no overheating issues (I also have A/C with a condensor mounted in front of the radiator). I live at 5,000' and typically drive at altitudes much higher also with no overheating problems. I even paricipated in the First Annual Iron Butt Challenge drive in late July last year. We drove over 11 mountain passes here in Colorado including several at 10,000' or more 550 miles all told. I had the A/C on the whole time and had no overheating problems at all. I pondered aluminum, but was put off by the price, mounting issues (they have to be isolated from the car), and fragility. I don't think you can go wrong with a three-core radiator fo a 240Z. Just my 2 cents.

Cheers, Mike

3 core.No such thing as "problems" getting air thru a radiator.

If you intend to buy a new radiator, get the 3 core. The difference in weight is negligible, and the difference in cooling is significant.

or would a nos stock 2 core work? just asking regarding cash saved. Otherwise 3 core it is, thanks for your guys' help!

I have a original '72 with my L28.

I did take it to the radiator shop and had them boil and rod it. No issues at all. I believe they charged my $45. I painted the radiator (except for the fins). Got a MSA shroud and all is good (without that big alum. radiator in the front!)

Edited March 7, 201114 yr by Travel'n Man

hmm, I was thinking bout another idea of a stock or aluminum 280z or 280zx radiator? they are cheaper, whether repro or aluminum. I heard that these will fit, although a little lower. I was wondering what the difference is between a radiator for a manual vs auto? I ask because I will be converting from auto to manual soon. Thanks!

Yoshi, when I lived in Texas and was having cooling issues in my '75, I replaced my 2-core with a 3-core, and it made all the difference in the world.

I personally wouldn't put a cheap aluminum radiator in the car. There's a lot of discussion of this on the Miata forums (where I also hang out), and a lot of people buying the Ebay aluminum radiators find that they leak. Quality control is generally pretty bad. The alternative is to install the OEM plastic-tank version, which eventually rots. I did decide to go with an aluminum radiator in that car. CX Racing came well recommended -- economical, and supposedly no leaks. I haven't found time to install mine yet, but I've looked it over. It's not flimsy. The welds are sort of ugly, but I suppose that's understandable.

I looked at cx racing but couldnt find a 240z radiator?? Back to ebay. Thank you for the suggestion though! Some stock 280z radiators are a 3 row correct? and it would be an improvement over the stock 240z 2 core? Also is there a difference between the automatic and manual radiator? Thanks for all the help, I really just want to get this right the first time!

There should be a difference between manual and auto radiators. The auto will have a separate inlet/outlet for the tranny fluid, generally at the bottom of the radiator. I suppose you could use an auto radiator for a manual tranny if you plugged the inlet/outlet connectors on the radiator. Don't know for sure, but it makes a bit 'o sense to me.

hmm, I was thinking bout another idea of a stock or aluminum 280z or 280zx radiator? they are cheaper, whether repro or aluminum. I heard that these will fit, although a little lower. I was wondering what the difference is between a radiator for a manual vs auto? I ask because I will be converting from auto to manual soon. Thanks!

This is what is in my 73 240, holes line up but you must remove the splash pan to make it fit, holds roughly 1 qt to 1.5 qts of extra coolent. P.S. it's an automatic radiator with the tranny cooler ports, no need to plug, just add rubber dust caps and you're set.

Edited March 9, 201114 yr by 5thhorsemann

Awesome, about to purchase a 280z 3 row brass and copper radiator. Hope it works! Thanks for all the help!