Best Radiator for Track Days?
 

What Radiator do the FD racers run on the track?? I've had mine for 3-4 months and finally got to go to a track day, I could only run 3-4 laps wide open before it started getting hot. When it got hot I started short shifting around 6k which kept the temps down. I've read where Koyo seems to be the favorite but I just wanted to see because I know most people don't take their's for track days.

I'm not sure what the exact temps are because I don't actually have a gauge. The guy I bought it from had the stock gauge mod and it started getting pretty close to the top white line so I backed off. But that is by far the hottest the car has gotten since I've had it, normal driving it only get about half way up at the most, and it only gets that hot setting in traffic with the fans off.

Also my car is mostly stock DP, Catback and I have move the battery behind the passenger seat.

I believe AWR offers a cross flow Ron Davis radiator that is very good. If you are going to track your car regularly, the complete system needs to be considered. There are a ton of threads, but in short, Radiator/AST/Dual oil coolers/proper coolant mix/ a ducted hood/and proper ducting and sealing of all air coming into, and leaving the engine bay. The last is one of the most important, and under acheived parts of the system. Some sheet aluminum, and metal ducting tape, combined with careful planning will make all the difference. Good luck, Carl

Skip the Koyo and drop-in Fluidynes IMO. Look for something that is atleast a two-pass for improved efficiency. That and the rest of Carl's advice is a good place to start.

Thanks for the info. I've already got a different AST, and it is an R1 so I've got those oil coolers.

Fluidyne or griffin...

What kind of intercooler do you have? I have a friend that up until last year he used the OE rad with no cooling problems, he is using an upgraded stock mount, he only got a Fluidyne becasue he got a good deal on a new one. If you have a stock mount IC then you propably have some other kind of cooling system problem. The stocker is good if you have clean air to it, aside from bursting the end tanks.

If you have a front mount and are looking for a drop in replacement, I say go with a triple pass rad, although aside from FEED ($1800) no one makes a triple pass rad. I am working on a triple pass radiator to be used in conjuction with a front mount intercooler, but it probably will not be done with testing until next month.

Oh I saw someone mentioned a Griffin, they are real nice, but you ahve to modify the lower radiator fan pedestals to get the fans to fit properly.

I still have the stock mount IC. The car cools fine daily driving, as well as at the AutoX, mostly because thats only about 60sec of running wide open. It will also cool down quickly from an AutoX run by just turning the fans on.

This was a small track and max speeds were around 95-100mph and it took getting on the brakes pretty hard to get that speed. It was also around 90-95deg outside. And when it did get hot, it started cooling down just from not running the rpms super high. Basically I could stay in 3rd all the way around the track if I went to near redline, but if I shifted and kept the rpm around/below 6000 it didn't get super hot.

I use a very large griffin, you can have them custom made to your specs in terms of flanges, endtanks etc. As I mentioned proper flow is so important. Remove any accessories that interfere with flow and relocate them. Also a sealed "box" will make a huge difference. I do not agree that a stocker is sufficient even for light track duty, unless you have a completely boxed optimized installation. At that point it makes more sence to design it around an upgraded radiator. Even if your temps are "tolerable", engine life is shortened by the higher operating temps seen on the track. Whatever sheet metal work you can do to direct ALL the air coming in to the oil coolers will make a large difference as well. If you have not already done so, you should invest in a quality mechanical oil, and water temp gauge, ones that you will always be looking at, not the display on a PFC for instance.Carl

any of you guys know if AWR's competition radiators for a FC is dual pass? I run a koyo at the moment, and am looking to switch

also carl post that info on your dual oil coolers soon:)

I'll try to post my whole "ccoling thread this week, a couple guys are waiting on it. I just need to take the low resoluion pics, everything is too large to post that I have. The AWR piece(not the mazdacomp), is described as a 2 row cross flow(side to side vs top to bottom= longer ime in the core). I also have drawings for my custom Griffin with an AST that I will post in the thread. The complete system allows me to run 20 psi for 20 minutes on the track with 200 water(at the thermostat), and 210 oil(at the filter). These are two of the two hottest places(right out of the motor), so some may have lower readings if measured at a different location.

i saw the crossflow one, but im wondering how much of a pain that would be to install, since it also needs the kit. And the fitment of the flexalite xtreme fan on it. The radiator i was mentioning was the competition direct replacment. If that one is dual pass

there are a couple of good threads in the 3rd gen Advanced Tech section about radiator ducting. it makes a big difference.

Resurecting this thread since I'm in the same boat as the thread starter, but it's 2 years later, so maybe there's some other radiator choices.

A search shows that the Koyo N might be a good choice:

http://cgi.ebay.com/ebaymotors/KOYO-...em140112266050

But is there one that will have fewer fitment issues? Will a fluidyne be adequate for "light" track use (is there such a thing?)?

I've been to the track once and had to do 2 slow laps after every 2-3 fast ones. I'm not currently planning to get into any serious racing; just informal track days maybe 2-3 times a year.

edit: I've read lots of threads about ducting and plan to do some of that too.

A fluidyne, in my experience, is perfectly adequete for even hard track use. I've never seen north of 99C in 30 min. runs in Virginia heat... and my car is still a twin turbo running 12 psi, and I lean on it QUITE hard.

I'm not sure you need a multiple pass raditor (there's a diminishing return there anyway, most of the cooling will happen half-way through the first pass).

Dual upgraded oil coolers with ducting (on the rad too!) are en excellent idea though.

I have a Fluidyne now and it is fine. I haven't seen above 95C on the track with ducting, lowered AC condenser, and a vented hood.

Don't skip the ducting and sealing. Be thorough. The importance of complete ducting cannot be overstated.

Regarding the "lowered AC condenser" - did you just pull it down/forward from the radiator? If that helps I'm definitely going to do it.

Thanks for the feedback!

I've got the dual pass Koyo in my FC, just some minor trimming was needed for the fan shroud, no other fittment issues. YMMV.

I run a AWR comp rad, and black magic xtreme fan that is shroud, and the fit is perfect, and temps are always solid. Ducting is a HUGE part of my temps, when some of my ducting comes loose, I can see a increase in temps during highway driving. Now I just need to upgrade my oil cooler, and Ill be good

I got the idea from someone on here, might be on this site http://reganrotaryracing.tripod.com/rx7main.htm. I do know there is alot of good info/how to's on there if you want to track your car. Its under the Engine & Control section. His is alot prettier than mine.

As for what I did, I basically unbolted it from the brackets, pulled it down, and made some more brackets out of some thin sheet metal I had laying around. I just bent the sheet metal into either and "S" or a "C", can't remember, just takes some time. There is an AC hose on the drivers side, I believe, that doesn't really want to come down. Might be something in the way or just didn't reach very good, it's been a while, but with a little work it either stretched around what was in the way or I got it pushed past it with some old fashioned elbow grease.

No idea if it actually helped temps, because I did it and the ducting at the same time. But I would think just from having a clear path for the air to go through the radiator it would help. It does however make the AC not work very good if you are in stop and go traffic.

on a side note if your car seems to be running hotter it could be your cats if there cloged

I see, thanks.

I actually did a similar thing because my condenser had been bent from a previous off-road excursion. It was pushed in very close to the radiator. After removing the bumper, I pulled it straight. In fact I bent it a little bit further and now my condenser stands further from the radiator in the middle. Another thing to consider; they all add up.

Dave

Agreed.. Proper sealing and ducting can make a huge difference. Also efficiency can be increased by using different pullies and higher water to coolant concentrations.

Agreed I did go to about a 20/80-30/70 coolant/water ratio plus some water wetter.

Now if I could keep my oil temps down around what the water temps are I'll be ok, but I don't know if that is possible with twins and the stock dual coolers. They hit 230-240F at the filler neck if I get 15+min of open track to run in, if not they stay around 210-220F. I'm planning cutting the inner fender well and put a louver or just a screen and see if that helps(if anyone has done this and has some feedback I'd be more than happy to hear if it helped. If not I guess I'm just going to run it like it is for now. I don't see me paying $1000 for oil coolers any time soon, or going single. I'd actually probably go single before I went with oil coolers, but I'd like to have a little more experience tuning before I did that.