swoope

iTrader: (5)

cant wait to read the mods to greedy rad to make it work thread..

beers

mysql

it won't be that bad:

step 1: sell the greddy radiator
step 2: buy the BHR radiator.
step 3: install and enjoy

swoope

iTrader: (5)

and save money.

beers

RevAmp

How about fans with higher speeds?
are there any good after market ones out there?

Brettus

iTrader: (2)

not specifically for the 8 - someone should do this .

Calling CRH !!!!

RevAmp

They seriously should

it'll be a good upgrade until you really need that radiator

ive been looking but no luck, wish they had on though

swoope

iTrader: (5)

note to all.

the CRH rad is done. you can buy it.. send him a pm..

and it does cool..

beers

nycgps

iTrader: (1)

That Radiator came out months ago. not just recently.

I've seen people use it in Hong Kong, its not that bad IMO, after a mountain run the water stay around 98 Celsius, and HK's weather is around 34-37 Celsius most of the year. so its not so bad (performance wise)

but price ... like all Made in Japan parts, they are never cheap.

sauceyI986

i knew BHR has a rad out i was just adding it to the list. But i know i am going to get the BHR for the turbo build im doing. The Greedy is a bunch of bling i think.

Flashwing

For many of us in Phoenix, cooling has been on the front lines of modifications to anyone's RX8. There's been numerous situations of RX8's overheating during moderate or heavy performance so it's clear (to me at least) that the stock cooling system isn't going to hold up under extreme temperatures if you're heavy in the throttle.

I didn't install temperature gauges until after my Koyo Radiator install, so sadly I can't speak to temperatures during that time.

The radiator is only going to be one piece of the puzzle when it comes to cooling. There have been examples of localized cooling issues with the RENESIS based on teardowns we've seen here on 8club, which cannot be solved with just a radiator. Even if you're not a person who tracks your car, spending a few hundred for cooling upgrades might make the difference with your motor.

I've ran the Koyo Radiator for about 30,000 miles and I can't say I've had any complaints about it. I did see some serious temperatures during last weekend's time attack due to the 100+ degrees it was that day.

Honestly, at this point I'd say the best solution for those looking for an upgrade from stock is the BHR radiator. The primary issue with the koyo is the tightly packed cooling fins. This system works well during cruising speeds, but at low speeds when the fans are the only source of airflow, there isn't enough air movement to provide serious cooling.

For those like me who have the Koyo, I'd evaluate your situation before upgrading. I hate spending money on the same stuff twice, and I don't feel right selling the Koyo to someone else because compared to the BHR I feel like it's an inferior product.

If I continue racing heavily, more so during the hot summer months, I'm going to have to look into upgrading.

Run as much distilled water as you can with Redline Water Wetter. This will utilize the full effect of your radiator system.

I'd also look into other items like the Mazmart water pump, greddy oil pan, gauges for monitoring your cooling system and perhaps some new hoses.

swoope

iTrader: (5)

bigger oil coolers??

btw, nice insight.

beers

Flashwing

Thanks swoope, yes bigger oil coolers are really something that's often overlooked and an upgrade I know I'm considering heavily. Another idea has been to add a RX7 oil cooler in series with the 2 other oil coolers.

I know MazdaManiac had been working on trying to outfit the current coolers with a set of high CFM fans but due to there being little clearance behind the coolers, custom brackets would have to be created. It would be easier to just replace the coolers with something better.

Again, all of these are just pieces to a fully working cooling system. Upgrading one piece won't yield many benifits without many others.

sauceyI986

yes i have notice when it is super hot in phoenix the car seems like it runs different like it doesnt have enough get up and go like when the weather is about 70 degrees

Flashwing

Depending on your setup and current flash there are various different reasons. Sucking in super hot air is part of it, but I know the newest flash retards timing when the temperatures get pretty hot. While it saves your motor, it reduces overall performance.

During the hot summer months, unless you have some means of monitoring your temperatures (gauges, scan tool, dash hawk etc.) I would just drive with some caution. The stock cooling system can become heat soaked easily.

As swoope pointed out, your oil system can easily become your bottle neck because even if your water cooling system operates well you still have to deal with soaking your coolers. My oil system takes much longer to become heat soaked but once it does I have no choice but to back off the throttle.

paulmasoner

iTrader: (1)

i recall a very 'in the know' individual saying that the OEM fans flow an ungodly amount of air already. the problem with them is they turn on after the car is way too hot. this can be fixed(AP).

and for the Koyo, like Mysql alluded to, it appears to have no real world improvment over OEM, and very likely is WORSE than OEM

and dont forget the BHR radiator, info is all over the forum

Charles R. Hill

iTrader: (7)

At this time there is a well-known shop who has had notorious issues with other rads. I sent them a BHR rad for flogging and if/when they give me their "thumbs-up" I will be fully satisfied with it.

As for airflow issues and performance in the "Real World", feel free to ask anyone who is currently using a BHR rad, A/T or M/T.

nycgps

iTrader: (1)

Where did speeddaemon go anyway? need him to add BHR's rad to the list

olddragger

iTrader: (3)

if you add more oil cooling capacity i would recommend an oil thermostat. you dont want the oil to take too long to warm up. i like the oil to be at 160f before i even take her over 4K.
there are several nascar type of coolers that could be hooked up easily.
olddragger

EricMeyer

You can have a custom racing radiator made for about $550 that is cool enough to keep your beer cold. We have worked with HOWE and had excellent results.

Mazda resells a Ron Davis that has very good fitment. I have owned several and can share this: Look at the distance of the path the water takes through the radiator. The longer the distance, the longer the exposure to cooling. Several RX8 radiators (no need to mention them) have a single pass path from the top to the bottom. You can see this by where the reservoir tanks are located. One tank on top. One on bottom. Let's call this distance X.

Now make/request/find a radiator with a dual pass (water travels one direction and then does a U turn and heads back the other. This is 2X.

Now change the path of the water from vertical to lateral and you have 1.5X for each direction. Add in the U turn and you have 3X over a simple single pass top to bottom.

This works. Tough fitment but it works.

Also, if you have a BIG *** air intake/K&N as big as a house setup in front of your radiator, you are not getting the maximum air to your radiator.

E

One thing to keep in mind

Charles R. Hill

iTrader: (7)

One can theorize design and crunch numbers all day, Eric, but I have yet to have anybody with cooling issues, whether boosted or not, with those $550 radiators of mine. I also back my products with the best warranty in the business.

To date, I am not aware of anybody who has bothered to even provide the A/T guys with a decent upgrade, either.

EricMeyer

The $550 number is for the custom radiators I HAVE purchased. I know nothing of your products and have made no mention of them.

My point is that there are custom options available to John Q. Public RX8 owner. I'm sure that's how you came up with your products. People should know and understand that every good product may have several design iterations and revisions and essentially starts out as a custom product. We typically have several items custom made which never become marketed. In fact (and this is for the purpose of sharing information with those interested in this post) the majority of custom high performance racing parts are purposely not shared or marketed because I don't want my competitors (and they don't want me) to gain an advantage. I would suggest to anyone interested to check out the Koni Challenge RX8 cars in person if you have the opportunity. Look closely and you'll find some custom parts. You'll also find many off the shelf stock Mazda and several wonderful aftermarket produts (like yours). The purpose of this forum is to provide an avenue to exchange information and unfortunately there are uninformed people posting what they think is factual. You and I know this. Everyone should know this.

Tell us more about your radiator since we're on the subject. Please provide as much information as possible. I think this would benefit everyone subscribing to this post.

Respectfully,

E

EricMeyer

Great question. I know of none. The custom ones we use (with big giant Setrab oil coolers that look like pizza boxes) allow us to easily operate at 180F. The SpeedSource cars use stock radiators and stock hoses. If you want to upgrade to larger oil coolers, you'll have to get new hoses and the installation is much easier when you drop the motor. We often have to tape up our oil coolers on cool days to RAISE the oil temps. Good question. Also, our water always runs hotter than our oil (most likely due to the massive oil coolers). Remember to MAKE THE AIR RUN THROUGH THE OIL COOLERS AND RADIATOR. An old racer trick is to take inexpensive window insulation you can buy at the hardware store and wedge it into any air gaps adjacent to your water radiator. This limits air escaping through the gaps around the radiator. Zip ties through the plastic belly tray can help keep the foam in place. We use the 2" x 2" foam. It's gray in color and about $5 for 6 feet or so. Don't forget the top of the front core support (where your hood prop goes). Air can escape UP too. If you go down this road do us all a favor and track your before and after temps. If running an aftermarket nose, make sure the air to the oil cooler and radiator HAS TO go through them.

Side note that hopefully will avoid any arguments: Some people will say that too much exposed radiators without air escaping will cause drag. I don't think this is an issue for the normal joe. Cooler operating temps are more important than lower drag. No response needed to this last comment please---it could be argued either way.

Side note #2---take a closer look at what the NASCAR guys do to tape up their tiny, tiny radiator openings to reduce drag--pretty cool. -http://www.beckersbakeryanddeli.com/images/Cakes/Car%20Nascar.JPG

Charles R. Hill

iTrader: (7)

There is a good reason why radiator manufacturers have little of the data you are seeking. Do your homework and find out why. Mac11 and I have been through this argument before.

As to your mentioning/slighting of $550 radiators, I knew you weren't talking about mine but most readers wouldn't have.

speeddemon32

First post updated! Sorry guys, this thread does not always get my attention. if something new comes up on any of my threads, please jsut send me a PM and tell me to update.


anyone have a link to the Gredy?

Mazmart

iTrader: (12)

Please, let's not forget the RE-medy radiator either which compliments our water pump. I don't mind sharing a little info about it:

RE-medy radiators by Ron Davis Racing: which is the highest quality competition type radiator available in the US. They are all aluminum with furnace brazed cores,the highest fin count in the industry. The cores are annealed and the tubes are welded seam. The core is 1.25" vs 1" stock. We've calculated about 5% more suface area and about 31% greater core volume. I may need to verify the numbers. It's direct fitment and costs $525 at our introductory price prior to shipping.

Here's a nice pic of a unit we have in stock now.

Paul.