Mishimoto radiator review; good and bad
 

I replaced my leaking stock radiator with a Mishimoto.

The bad first:
1. Top mounting holes on the Mishimoto are too small to fit the stock rubber mounts and are slightly too close together.
The fix was to remove the small top brackets that reach from the frame to the radiator and dremel their holes 1/8 inch allowing the stock brackets to be 1/4 closer together. This does not resolve the fact that you cannot put the nuts on the stock rubber top mounts, wire ties were the solution, the stock rubber mount bolts go through and wire ties hold the rubber tight to the Mishimoto radiator bracket. I consider this a temporary to perm solution until I can make a better top bracket or come up with another idea.

2. The AC mounts do not protrude from the radiator like the stock AC mounts; the fix is to bend the AC condenser bracket, which also moves the AC core further from the radiator than stock. I consider this a permanent fix.

No other negative points.

The good.

The radiator is a work of art to look at, almost a pity it is hidden.

My temps have dropped dramatically, even with NO SECOND RADIATOR!
I drove with the AC full blast, in Orlando's 97 degree heat of the afternoon and my temperature never went over 194, again this is with the second radiator I had installed years ago removed.
Before my stock rad started leaking, when I had the stock rad and the secondary rad, my temps would climb when the AC was on till I chickened out and turned the AC off around 203 to 215 degrees.

The stock fans fit the mounting points perfectly, no fitment issues at all.

The Mishimoto core is two rows of tubes compared to the stock single row, and is more than a half inch thicker than the stock rad core. (Mitishimoto lists it at 1.57 inches thick)

I recommend the Mishimoto radiator for anyone needing a replacement radiator as long as the person doing the replacement has a little fabrication skill.

$277 from Summit racing, I also had mine come with free shipping....

I had a problem with the top mount too which is an easy fix.
Get a 1/2" aluminum angular bar..cut it in length..drill holes..and that's it..cheap fix..
For tha Ac condenser, mine fits well.
For the fan assembly, i drill the mounting hole a little bit wider because its a little off.

I still preferred with mishimoto rad.

Thats pretty impressive it helped knock off that much heat. 194 degrees, was that stop and go city traffic or highway? I'm on the stock rad looking to upgrade and my usual city temps with the A/C on full blast gets to peak to about 207 degrees in stop and go traffic. On the highway I average between 185-195ish degrees. Off topic a bit but does any one happen to know what temp the cooling fans kick on?

Rote8:

When I replaced my OEM radiator at 106,000 miles with another OEM replacement radiator (Koyo brand), I also saw a significant drop in coolant temps (or rather, the radiator was better able to keep the coolant close to my thermostat and fan target temps). The Mishimoto itself is not the reason for the drop. The drop is simply that your radiator is no longer an old, decaying, and possibly clogged radiator. With my 172F thermostat, the Koyo replacement was holding ~175F on the highway, and was holding around my fan temp of 180F in stop and go.

My replacement radiator had zero fitment problems, and was cheaper at $150 + shipping from Mazmart, a forum vendor (for the same net cooling improvement).

Mishimoto has a pretty poor reputation on a number of forums, almost all because they have fitment problems on nearly every model they make, cost more than the OEM replacements, and still retain plastic end-tanks, which are more failure prone than all-aluminum construction. Mishimoto is essentially still an ebay brand company, just they got enough volume/profit to pass themselves off as a "brand name". Their quality is still pretty poor. Not much reason to pay 50% more for something that doesn't even fit properly when the cheaper one does.

I'm glad you got a replacement radiator in there and are seeing your results, but ... well, you could have done it for cheaper without any fitment hassle, so it's hard to applaud the result :) (no offense intended)




GK1707:
207F is when the fans turn on, which is why you are seeing 207F in stop and go traffic :) Under that, the fans aren't running, so the radiator isn't shedding much heat at all. Ideally, you should reduce the fan trigger temp down closer to your thermostat temp. 180F is popular.

The one i got was all aluminum and i think its closer to $300...
I was looking for Koyo(all aluminum) at that time but they were back order..

Mine is all aluminum and has dual rows in the 1.57 inch thick core not a single row 1 inch core like the Kyoto.

And Mishimoto is not an ebay company.
Aluminum Radiator, Performance Radiator, Cooling Products - Mishimoto Automotive

Just because they have their own website doesn't mean that they didn't start out as an ebay only company :)

Still, given the problems you had, I am not sure I would recommend it over one that has better quality (ie, direct fit), and lower cost. For not all that much more, you could have gotten a bigger radiator that also fit perfectly.

Feel free to do some research, you don't have to believe me. Mishimoto has a very very poor reputation, largely because of fitment problems on something that they could have taken a few minutes more to get right. If you want to defend it because it has fitment problems then....:dunno:

Sorry for the fitment issues guys! Product feedback is always welcome and we appreciate the voicing of concerns. We will investigate further and see if we can make any adjustments that will provide improved fitment. Great to hear that the radiator is making such an impact on coolant temperatures.

Thanks guys!

Companies start out in a variety of ways, it is unfair to use that as a determination for their future or present outlook. Mishimoto has grown substantially and rapidly through several years of providing high quality cooling solutions. Yes, we have developed products in the past with fitment issues, but I think you will find that our current line of products are of extremely high quality. We are constantly improving our products and we keep a close eye on warranty returns and complaints to ensure that each of our products have an extremely low warranty rate. Our overall defect rate is well below industry standards. That being said, we are always looking for ways to provide better value for our customers and we will certainly investigate the concerns outlined above. Thanks for the feedback!

Our facility in New Castle, DE houses our corporate HQ as well as our engineering facility. We design and test all of our products in-house. Our garage features an array of fabrication equipment as well as a Dynojet dyno. Check out the link to our engineering blog below which shows our processes and projects going on at the moment!

Mishimoto Engineering Blog | An inside look at the engineering of Mishimoto products.

http://engineering.mishimoto.com/wp-...-Cooler-31.jpg

http://engineering.mishimoto.com/wp-...0-1024x768.jpg

http://i60.tinypic.com/htbi1k.png

Thanks

While I applaud your initiative to come here and respond directly, you won't make me a convert until I stop seeing threads complaining about the fitment problems of your radiators.

RX8Club.com
Miata.net
Mazda-speed.com
TurboMiata.net
Mazdas247.com
...are just for starters where I have seen complaints.

I also easily turn up complaint threads on many other non-Mazda forums.

This isn't a 1-off complaint from even just 1 model. It's a pervasive problem across a huge range of models that you produce for. If you are really as serious as your message would have us believe, you would be ensuring that your radiators all actually fit, and yes, I expect that it would be a significant undertaking to resolve it all. IF you do, then good for you and I will be the first to praise you for doing so. Otherwise, it will be the same story, and I will have the same recommendation that I posted earlier.



Your actions will speak louder than any words you can post. :) :icon_tup:


Moderator Note, aside from any personal opinion:
You aren't a paying vendor here, and while we welcome your involvement in the community, be very careful of what links/info you post and ensure that it doesn't violate the forum rules regarding advertisement from non-paying vendors. Just a friendly note calling your attention to it.

Unfortunately I share the same sentiment as RIWWP. One search of Mishimoto radiators on google brings up numerous threads, all of which contain one post or another about fitment issues. I am very hard pressed to ever recommend one of their radiators based on the feedback and the lack of problem resolution that I have seen.

Again, it is nice that a product vendor took the time to respond to the thread, but it would be nice to see some physical action performed to bring the products up to the quality and fitment standards that we expect when we spend our hard earned money

I have installed Mishimoto rads in both an EVO and an RX-8 and both fit very poorly. This was over a course of quite a few years so it is obvious that neither fitment or QC is a high priority for Mishimoto despite what they say. I also know of a few RX-8 owners who had fitment issues with this rad as well so it is not an isolated issue.

Also, Mishimoto offers no data what so ever on the RX-8 unit (or really on any of their coolers). Just because a radiator has dual cores (not to be confused with dual pass), doesn't make it better than the stock rad (which is very good BTW). Good look up coolers from the likes of Fluidyne, etc. you will see a data sheet for each cooler showing you how efficient it is.

Rote8, as RIWWP pointed out, you replaced and old radiator with a new one, so of course you will see an improvement :duh:. That does not make it better because had you installed a new stock rad you would have seen an improvement as well, and spent less money.

Wow, I never expected a large thread, I too had heard of fitment issues, but the Radiator is much thicker than stock, and has two rows of tubes to the single row of the stock Mazda radiator and most replacements, fitment was not my deciding point!!!!

I have modded my cars mods before....

Yes, the top aluminum top mounts tabs on the RX8 Mishimoto radiator could be 1/4 farther apart, and slightly longer tabs would make it easier to attach the top mounts. That is not bad.

~ not an issue for me, the cooling for the price was my deciding factor.

I would like to express my delight at a well made product, not complain because a radiator doesn't match the smaller stock radiator...

Sometimes I have no wonder why few companies make products for the 8 anymore, too many whiners are not blower whine....

Rote8, so what do you think sheds heat quicker, a thinner single core with a rather good fin density or a thick dual core with a rather less than ideal fin density? And what do you think happens to the factory fans ability to pull air thru when you slap them on a thick dual core?

The typical Ron Davis racing radiator is a 3" thick 2-row core. Don't believe all the BS you read on this forum about being too thick etc.

... but ...


If it was well made then it would fit properly, like every other well made radiator...

Subjective opinions on what performance of the product is without a single shred of performance evidence isn't proof of a "well made product", where as substantial proof of pervasive bad fitment from a company that ignores complaints about fitment is pretty big proof against calling it a "well made product".

You know what's worse than people "whining" about poor fitment?

People giving good reviews to sub-par products.

don't worry, you get used to the gushing koolaid guzzlers over time

I don't mean to be overly redundant with what has been stated previously, but fitment was consistently an issue with mishimoto for the 5+ years I visited the miata.net forums on a daily basis (and specifically why I did not opt for a mishimoto radiator when I replaced the radiator in my miata). I hope the aforementioned post by the mishimoto representative is sincere in its intentions to improve product quality by listening to its customers. Until then mitshimoto remains on my "no-dice" list while I look for ways to increase my cooling capabilities.

TL:DR - Make the damn things fit! Rote8 gave a pretty detailed outline as to where to start....

i thought that I'd update this thread. I just installed (or almost installed) a Mishimoto radiator in my 2004 RX8 (manual). Everything went fine until I started connecting the upper radiator brackets. I had the same issue as Rote8 described. The upper bracket tabs on the radiator simply aren't long enough. The result is that you cannot get the nut into the bracket to install the OEM threaded bushing (this connects to the bracket that bolts to the frame). It also means that the bracket alignment won't meet the frame holes. I've attached photos. It's a shame because the right solution is to make the tabs longer (and weaker) or to simply move them closer to the top of the radiator like in the OEM radiator. Photos should help folks to understand.
https://cimg3.ibsrv.net/gimg/www.rx8...1951083fc9.jpg
https://cimg4.ibsrv.net/gimg/www.rx8...d839e5837c.jpg