I have an eBay honda half radiator in my car at the moment. And it seems to work just fine cruising and doing street pulls and what not.

But when I went to the dyno. We could only do a pull or two and the car would start to overheat.

So my question is. What is a good half radiator? Anyone have any luck? Or is it just simply that a half radiator is just to small. I've seen some thicker ones. But tthey don't seem much thicker

 

The Ebay radiators are trash in most cases. Because the car only overheats on the dyno, inadequate airflow is the first thing I would think to address. Do you have a shrouded fan setup on there? And a legit fan as well? Those two will make a huge difference, not to mention getting rid of the oem fan controller because it operates at two different speeds. Also were you guys running the dyno fan? If these things dont help, I would recommend a Koyo/CBRD/ToxicFab/Buschur unit to replace the ebay one.

In response to your question about half radiators being too small in general, I've got multiple guys running my FF AC kit on their cars with Koyo rads and have not had any reports of them overheating. Not to mention there are a lot of people running ff cars without complaints. Thickness is not necessarily going to make the difference as much as a quality core design will. Because the half-rads have so much less coolant volume and surface area, its possible that a thicker core will get heat soaked and remain heat soaked longer than its thinner-cored counter part.

Toxic's rads are dope and i believe he uses cores no larger than 1.75" thick, while recording the same if not cooler operating temps than cars running stock rads. Buschurs are also very nice, built by fluidyne and I want to say they are triple core. I dont have any experience with CBRD but if you've seen any of their stuff, you know the quality is top notch.

 

thanks for the help! yeah i have a legit fan, the only thing is its on the front of the radiator and its setup to push air (cleaner look) i was wondering if it would be better to be on the inside setup to pull? and yes i also use the factory controller... you think i should just wire it up to run constant?

i will definitely have to look into a better radiator. just wondering on the specifics of fan placement and controller

 

I had a mishimoto half size with a mishimoto 12" fan pulling from the inside ran off the stock fan controller and never had a problem with overheating. A shrouded fan should work even better because you're then using more of the surface area to cool when the fan kicks on. I just replaced mine today because I didn't like the big gaping hole on the passenger side left when I deleted my ac. You can check out my posting in the for sale section if you interested. Other than that the radiators listed above are great options.

 

oh yes, definitely. I know its not as clean, but all electric fans are rated for puller configuration. If the fan claims to flow 1500 cfm, I imagine it flows at least 300 cfm less when its pushing. Try flipping the fan to the other side (dont forget to flip the blade and the polarity so its pulling correctly, I almost always forget) and add a shroud if you can. I would do this first since its easiest and you wont have to mess with the controller wiring, not to mention its pretty annoying when the fan comes on with the key IMO haha. Just wondering, you have the oem thermostat in there still right?

I actually have an aluminum shroud that I built for a Koyo that never got used, it hasnt been cut in the center for the fan yet but if you need it let me know, id sell it cheap.

 

Hey guys,

Just chiming in here to let you know we are working on a bolt-in half rad for the Evo 7/8/9.

We have a build thread going on at the link below if interested!

https://www.evolutionm.net/forums/vendor-announcements/681667-mishimoto-build-thread-evolution-7-8-9-half-size-radiator.html

Thanks

 

Looks really nice, the only thing that concerns me is the "short spring racing events" usage part. With ff setups becoming more and more popular and many of these guys running them on their street cars and daily drivers, I worry that this rad won't keep the car cool in those conditions? Or do you guys just have to say that to cover yourselves against potential issues, the same as koyo? Not trying to be negative, just curious. Thanks

 

And I know it's tough to cut the cooling capacity this much and expect oem results, it's a lot to ask considering the scenario

 

Just out of curiosity, does anybody have experience with a full filled block and using a half rad? I am looking into a rad setup for my car which has a filled block and I am concerned if an off the shelf half rad will be efficient enough?

 

my honda half radiator cools just fine to DD in extreme heat and your average pull here and there all day. but if its 85-90* and i do a few back to back pulls or on the dyno(even with like 4 cooling fans blowing on it) itll overheat quick.

i was just wondering how your guyses koyo buschur, fluidyne, half radiators are performing on that aspect, and if they cool that much better to be worth the 500+ dollars.

and also was wondering where you guys mount your fans? mine is on the front setup to push air thru(mainly for aesthetics/cleaner bay), would it be more efficient if it was on the back setup to pull so more air could contact the radiator surface directly from the front?

thanks

 

Yes, moving it to the back would definitely help. All of these electric fans that are rated for "X" CFM were rated for a puller configuration.

 

Hello Alex,

Sorry for the delayed response! Although it can be done, we do not recommend this for a daily driven vehicle. Despite a very efficient radiator core, the reduced capacity has quite an effect on the radiators ability to recover from temperature. If you are in an extremely warm climate and plan to make numerous successive pulls, temperatures may rise to an unsafe levels. If you are driving normally or allow the coolant temperature to recover before the next pull (short road course, autocross, rallycross, drag, etc.), this radiator will perform perfectly. All of this depends on your vehicles power, boost and actual heat generated, so results will certainly vary.

Let me know if that adequately answers your questions!

Thanks