I went out to ECR this weekend for the toy run. I took some advice form a few of you, Hustler in particular, and taped off the hood vent on my car and the bumper vent.

the first two session in the morning were ~40 and the car overheated in a few laps at a slow pace and didn't cool down until I dropped to about 40mph and then it cooled very slow.

In the third session I removed the covering off the hood exhaust vent and went back out on track. It was warmer then, ~60 but the car still rapidly got too hot and took forever to cool down. For the fourth session i pulled the cover back off the bumper vent, conditions were roughly the same as session 3 and went back out. the car stayed at excellent temps the whole session. You can see the temp gauge in the video below of the last session. Note that on the later laps it starts inching over 230 at the end of long straights, however it quickly drops back to ~220 as soon as I lift to enter a corner.

With the bumper vent open the car simply stayed cool and cooled off much much faster when it did get hot than with that bumper opening closed, and did so in warmer temps with me beating the crap out of the car to a new personal best time.

I also ran into the guy that owns trackdog racing at the event and had him look over the car. His advice was get a reroute, he said he saw about a 20 degree reduction in temps with his installed (if 20 degrees is right i would be golden, the car likes to run 245 if id let it). He also suggested moving my oil cooler out of the stack and into the passenger fender well area. He also suggested going from the single factory fan the car has to a dual spal set up.

the reasoning was if you need more flow you can either force air into the rad or pull it through with fans. he said the reroute and other work would take about 8 hours labor (about $1000 total for the work). I don't have the tools, time or inclination to install it myself. what say you guys on how long it takes to install the reroute?

he also said that getting a thicker radiator wouldn't fix the problems, only delay them. while that is true is I am thinking that if (for arguments sake) the narrow 37mm koyo heatsoaks in 5 minutes at speed and the fat TSE rad heatsoaks in 25 min, that is as good as fixed as i see it since i can effectively run a full session ***** out. Am i missing something?

 

Just fyi, I don't have a reroute and my temps don't move from 195. I had my car back on my lift last night and I took some pics of my ductwork for you if you are interested. Also, can you take a pic of one of those fasteners on your turbo/downpipe? I am trying to get the numbers off of the head of the bolt so I can source some. Nice meeting you btw, did you know the guy that I was arguing with? Kind of interesting that he was an aerospace engineer, the pressure zone profile on the wing is much like a miata so that was odd that we disagreed so much.

 

for $1000 I'd fly out to TX, (if you put me up for the night) and I'll do the reroute for you for free.

And I'd still make out well...

 

LOL, that was parts, moving the oil cooler, labor and for a pair of fans too

Mach1, was nice to meet you too. i dont know that guy you were talking too. i was fighitng the worlds strongest duct tape to get the bumper cover off and he walked up and started lending a hand. He was one of the instructors, but i forget his name.

I'll get out there and try and take some pics of those weird bolts, the ones that hold the turbo to the manifold are the same ones that hold the downpipe to the exhaust system. that was the third hard track day in that car and they have held with no issues at all. that said, i do have an exhaust leak at the downpipe/exhaust junction that has always been there. it was there when i picked the car up. i suspect the surfaces of the DIY 3-inch exhaust and downpipe from FM don't line up exactly.

Yeah id like to see your ductwork.

 

Sure, if the fans are 18" in diameter and crank-driven. Twin 12" Spals aren't even going to come close to providing the necessary airflow through the radiator to effectively cool a track car. I know because I've tried.

Fans are for A/C equipped street cars. If your track car is overheating, you need to duct it from the front - no electric fan will come close to being as effective as a little bit of ABS ducting.

Yep, you (and TDR) are missing something big: Thicker radiators do more than simply add water to the system. Thicker radiators add heat rejection ability which drops the equilibrium (operating) temperature of the system. Dual-row radiators do an even better job of this by significantly increasing the amount of transfer area between the incoming air and the coolant in the cores. A car that runs 230+*F with a Koyo 37 or a Koyo 55 will run <200*F with our radiator, because our radiator sheds more heat than the single-row Koyos do.

I don't know when this idea of "bigger radiators delay the problem" became popular, but it's total bullshit.

 

I want some of that action then, if your rad does what you say it will fix my issues. I also need to fix my ducting, but the tiny rad i have needs to go.

Question for you though, i know from reading the description that your rad mounts in the stock place. My oil cooler is mounted to the spots where a second fan would go on the koyo. I assume with your much thicker radiator, that oil cooler will need to move, correct? the oil cooler is no thicker than the stock fan that is in place on my car.

 

Our rad is set up to use a single stock fan, so you may need to move the oil cooler.

 

Savinton knows best here without a doubt.

I'll just add my 2c. My first turbo motor had a Koyo 50mm and would still overheat at high revs on track (at no other times). With a re route (949's one) it would not overheat on track.

Strange thing is my new higher spec motor package with some after market aluminium RX7 rad doesn't overheat at all WITHOUT the re route. The new rad is very similar to the old one, maybe slightly thicker but not crossflow or anything. It must be a magic one.....

I would recommend the re route from my experience. It worked, you can fit it yourself and it doesn't cost anywhere near $1000.00......you may not have to relocate your oil cooler and you may be able to retain your eisting fan setup.....

 

A reroute should be an integral part of any car that sees a lot of track time. We keep M-Tuned reroutes in stock.

 

oh wow, this is exactly what i've been telling you all along!!!

 

You've been mulling over this **** for half a year. You need a 55mm radiator, sealed ducting on the front of the rad, belly pan, reroute, your hood vent sucks.

No one ever email me questions again, it's not worth my time anymore.

 

If the ducting is not right, nothing works. You need to duct every heat exchanger.

 

Dude lol, i know what you have been telling me. i was relaying what someone else suggested at the track. and pointing out that closing the bumper made overheating worse. don't be hatein'

 

What do you mean closing the bumper?

Ahh I now see that you have a hole cut in the upper section of your bumper. Why is that? It seems like that would make things extremely hard to duct.

I would also trust Hustler and Savington over the TDR owner.

 

It has a big hole in the front bumper for cooling, see attachment. After many recommendations that it was hurting cooling, i used abs and racer tape to seal it up at the track, it made cooling much worse with the hole sealed.

 

Well without proper ducting of the radiator I could see how that second hole could help with cooling. Just because it helps some when the rest of the system is not optimized, does not mean it is actually effective. I would follow the advice given and do TSE radiator, coolant reroute, proper ducting of the lower opening, and then close the upper hole in the radiator. If you were to put your oil cooler there and then completely duct around the oil cooler into the radiator the upper hole will still help, but I think doing that would be next to impossible.

 

Wait, so ducting forces air into a space and is directed through the heat exchanger not around it?

 

Ssshhhh, Brain, that information is Top Secret, I have reducted it for you.

 

Agreed with everyone else. Your ghetto bumber vent only helps because the rest of your setup is so fail. Do not purchase one freakin thing for that car until you duct it correctly from nose to radiator, seal the retarded vent, and run a splitter under the motor or the factory under tray.

 

i plan to fix things, and fWIW i didnt cut the bumper it was like that when I bought the car.

the problem for people new to miatas like me is that half the people you talk too or that look at the car say one thing, the other half says something else entirely and then people want to get pissy when you ask more questions and bring up something that was recommended by that other half.