zikizira

Hi,

I have raced my 2008 Evo X GSR this last weekend in a road circuit. I have logged all the first battery (about 20 min) with EvoScan and found that I have reached 108C (226F) at some parts. Is this expected?

Here my mods:
- AMS Test Pipe, Twin Cat Back;
- AMS CAI;
- AMS FMIC + UICP + LIPCP;
- HKS Evc-S EBC;
- Mishimoto Radiator + AMS Hoses + Water Wetter (1 bottle);

During such session, I have peaked 21psi (have tuned for 18 to 25 psi), 11.2-11.5 AFR while WOT'ing and got no noticeable knock, although substancially timing advanced. The outside temp was about 25C (77F). I was shifting at 7500 and did a lot of engine braking (until 8000 rpm, sometimes even more), since the brake pads werent performing well.

Is the thicker FMIC the culprit, as in my DSM Eclipse?
I have already purchased a Race Thermostat. Would this help? What else could I do in order to reduce engine temps?

Thank you,
Ziki

blk-majik

iTrader: (6)

I know it sounds like a band-aid (because it is), but have you added any Red Line Water Wetter to your coolant? They say it can drop coolant temps by 20C, but in my experience it's usually good for about 5C. Every little bit helps!

The thermostat seems like a logical cheap and easy step, so I'd say go for it, but I'd also consider beefing up the brakes. It'll not only save you from having to engine brake (and thus reduce temps), but it'll make you safer and quicker I'm running this brake kit and it freaking rocks: http://thebrakeman.com/evo_kits

turbotaloon95

iTrader: (7)

I'll preface this by saying this is just my opinion, but you are surprised your car got a little hot after driving it hard for 20 minutes? Of course it did. Your stock cooling system wasn't designed to handle intense driving for long periods of time.

Yes, I would consider upgrading your cooling system if you will be tracking the car (especially on hot days). Some smaller/cheaper things to try first are:
1) Cooler thermostat (which it seems like you purchased)
2) Run more water in your coolant mix. Instead of 50/50 try 70/30 (water/coolant)
3) Add some Redline Water Wetter, or similar product.

If it still runs warm, try upgrading your radiator and fans. Good luck.

ugakirk

iTrader: (14)

Are ya'll not reading his initial post? He says he has the Mishimoto radiator and Water Wetter.

With alot of heavy driving like that and the upgraded FMIC I would assume thats about the right temp. I would try like they said and dilute the coolant some and put the new stat in. Have you upgraded anything with the brakes, like.. brake fluid? If not, that will help the brakes on the track because you were prolly boiling the fluid. Get racing fluid.

turbotaloon95

iTrader: (7)

Wow, totally passed that one up..whoops!

Hiboost

iTrader: (9)

The cooler thermostat will delay how fast it warms up to 180* F initially but once either one is full open past that temp it won't make a bit of difference keeping the car cooler. You need to do things that will actually incease your cooling reserve capacity itself once the thermostats are full open. As for engine braking, that should actually help cool the engine if you aren't over revving the engine say past 6k. I would get a better braking setup so that it's adequate for how hard you are trying to drive the car since over revving just once can float a valve and that is no fun. The rev limiter only helps to prevent the car from accelerating past the rev limit, downshifting it and forcing the clutch to engage will make the drivetrain spin past the limiter and ruin your day and is not worth the risk.

1) Redline water wetter - This helps but the ratio of water to coolant makes it quite a bit more effective. Going pure water if it's not freezing in your area would easily double the effective cooling boost you get from the product. Even switching to 60-80% water will help quite a bit.

2) Upgraded radiator - You probably have the standard Mishimoto like I do which should be helping increase your cooling capacity you have in reserve. They did just release a thicker model, I think the stock is 1", the regular is 1.5" and the Mishimoto X line is 2.0" thick.

3) Airflow through radiator - Make sure that every bit of airflow that enters the front of the car reaches the radiator. I've done things such as rotating the stock horn 180* so that it sits right behind the Mitsu symbol. While you might think this is minor it probably allows an extra 5-10% airflow to reach the radiator. Do enough of these small tweaks and it adds up. There are also some gaps on the sides of the front bumper cover where air can flow under and to the side of the intercooler. I actually used zip ties and the corner of a long black plastic wastebasket cut up to force air to move through the intercooler core and radiator, it looks factory!

4) Run the heat during hot laps - Sounds crazy but it's that much more heat that can be removed from the system while hammering on the car. Granted it can make the cabin unbearable but if you have both windows open and aim the vents outside, you really won't feel it and it will help the car. When pulling into the pits after doing a cooldown lap for the brakes, make sure to pop that hood to let that hot air escape once the engine is off as well. A good indication that the car is getting too hot is when you shut it off and the fans stay on. I forgot at what temp that happens at but the first 20-30 min you park the car, temps skyrocket since coolant no longer circulates.

5) Underhood temps and hood vents - You can modify the main hood scoop aluminum heat shield and remove the slats on the two smaller vents to to increase airflow as well. The exhaust manifold area should be fine assuming you have the stock heat shield in place, get it covered with something if that is removed. I've read people placing DEI Cooltape or other heat reflectant on the coolant pipe that runs on the back side of the block, no reason to let all that radiating heat soak into your cooling system if it doesn't need to! Coolant/oil lines leading into and out of the turbo can also be covered so that the exhaust manifold heat isn't adding to the problem.

6) Conservative Tune - Make sure you aren't knocking at all as even minor knock can really incease head temps over time. Timing advance down 1-2* and boost kept 2 psi lower than normal should help ensure there is some safety margin when you hammer on the car. If you are unsure, you can add some 100 unleaded race fuel and compare knock and resulting temps on back to back runs. The car should run cooler if no timing is pulled with a higher octane mixture of fuel.

7) Increase Oil Cooling - If all of that doesn't keep you in check then look at upgrading your oil cooler in some manner. The more heat that it can shed, the less load it will have on your entire cooling system. More oil capacity will also help since it will take longer for it to all heat soak. There are also some gaps in the air ducts around the stock fog light that can be closed up as well to force more air through the stock cooler.

There may be things I'm forgetting at the moment but I'll come back and edit this if they come to mind or someone chimes in. No one mod will be the cure all but do enough of them and it will really make a difference.

Xtremist

iTrader: (1)

Buy a 160 thermostat, that will solve the issue lol. I'd really watch overheating these alum. blocks though!

zikizira

Hiboost,

Thank you very much for your tips. I have read all your posts related to your track experiences. As a DSM owner myself I have tried every kind of tricks for keeping temps low, but there is always new tips to learn.

Actually, my concerns are:

- Is there something wrong with my car, since I havent raced it too hard this time, had just bolt-ons and max 21psi? I wouldnt expect overheating problems so soon.
- Is 108C (226F) normal/acceptable for the Evo X?

If such supposedly overheating wasnt expected, what could be possibly causing it?

Regarding the brakes, that was my bad. I shouldnt have chosen Hawk HPS. I only use DTC-70 in other cars, but this Evo is also used as a d.d. car and I wanted to keep noise at a minimum. Now I am ordering a separate set of brake discs and pads for track abuse.

Thank you,
Best regards,
Ziki

Hiboost

iTrader: (9)

You wouldn't think that low boost would cause issues, even if the timing was somewhat more aggressive. Usually 1 psi is roughly equal to 1* of timing advance from a HP production perspective so they go hand in hand. The only trouble is when revving the car between 5500 and 7500 rpm's you are in the area where the stock turbo tapers boost anways so the difference between higher boost levels actually isn't as large of a factor.

5500 - 25 psi - 21 psi
6000 - 23 psi - 21 psi
6500 - 21 psi - 21 psi
7000 - 19 psi - 19 psi
7500 - 17 psi - 17 psi

So perhaps from 5500-6500 you are running slightly lower boost which helps, but from 6500-7500 it's likely going to be the same as someone running higher base boost at lower RPM's. Couple that with aggressive timing and you might actually be knocking up top when the car gets really hot on the track after 15+ minutes.

The only thing to watch out for is if you are pushing coolant into the overflow bottle. It's possible that with enough knock and high temps that you can stretch the head bolts slightly in extreme conditions lifting the head and weaken the headgasket in a few places. Once compression gasses force themselves into the cooling system it all goes downhill from there when trying to keep the engine cool. It was much easier to do this to the DSM engines on the track but I think Dave Buschur overheated his Evo X at the track once with a larger FMIC and no upgraded radiator, although he was still running a bit more power than stock with the Dom2 turbo at the time.

gizmotoy

Is overheating with a FMIC and no upgraded radiator a common problem? Your comments make it seem like that may be the case, but I haven't see that mentioned here before. If so, ... maybe I should cancel my upcoming track day.

dreamerak

I dont think a water temp of 226F is over heating your engine. 240+ then you can start being concerned. The more important question is what are your oil temps?

Hiboost

iTrader: (9)

It really depends on how hard you push the car and for how long. If you don't upgrade the radiator you can still do some of the other low cost tweaks on that list and you should be fine. Also driving for a cooldown lap every 10 minutes of hammering on the car is a good idea for the brakes anyways and that should let your cooling system catch up again to close to normal temps. I wouldn't cancel it, just plan accordingly if it's really hot out.

turbotaloon95

iTrader: (7)

Typically I've seen large front mount intercoolers becoming an issue in 1g and 2g DSMs where they block about 90% of the airflow to the radiator and therefore reducing it's efficiency.

skyseer

Is it ok to use additives such as water wetter with coolant/water 50:50 mix ? I thought it can be used only in straight water cooling systems.
Any opinions about Motul MoCool ? Since I don't have access to Redline products.

HxllxMan

iTrader: (6)

Have you check if you thermostat is not stuck closed?
Might be dumb, but can happen...

And also what type of viscosity do you use?
If you do use 10w40, try 10w50 especially in hot tropical place.