Hey everyone my temps rise alot after crusing for more than 5 minutes. I recently added a Greddy FMIC and thats mostly what has caused high temps. Max temp while driving in city is 86C(186f) but after 5 minutes of crusing on highway temps jump to 94C(201F). It only gets hot like that from crusing not from idle. Max idle temp is 86C. Right now i have no ducting to the radiator because my stock pieces aer torn up adn i am in the process of making my own anyway. But do you guys think i need to upgrade to a koyo or should i just do the ducting and that will do the trick? Oh yea i live in florida adn summer is approaching so temps are rising.

 

What do you mean by ducting? The underbody pan? Or are you talking about the plastic pieces where the relays sit behind the bumper skin and between the rad support? I have a koyo and on the freeway while accelerating it will sometimes hit 87*C but drop back down once the tstat opens some more. I have alot of my bumper cutout, maybe you need to cut more out also? I have a stock clutch fan and shroud with stock underbody pan as well.

 

I mean i haev NONE at all, no top pieces or not belly shroud. But i am going make new ones out of metal. I have a stock s5 bumper with just the grill cut out. I dont like the look when more of the bumper is cut out so im not going to do that. I have a fiero Efan that comes on at 86C.

Basically what im asking is will just the ducting do the trick or do i need the Koyo also? no matter what i am doing the ducting.

 

Ducting will probably solve your problem, make everything feed right to the rad and don't let it escape around it. At high speeds the fins in the rad act like a solid wall if the air isn't forced to go through it once its through the grill area.

 

I cant say if the koyo with ducting will keep your car cool. Even if you force all the air in through the cutout grill area of the bumper there is still alot of surface area that could be used to maximize cooling. Try the ducting without the koyo and see if it helps. If it doesnt upgrade to a koyo. If it still doesnt you gotta do some cutting or your problems are elsewhere in the cooling system.

EDIT: maybe try switching back to a clutch fan after you do the ducting and see if it improves the cooling. I know some people have better luck with clutch fans but there is always an exception.

 

Why spend a bunch of money upgrading the radiator when you already know a lot of the air entering the front of the nose isn't being used for cooling? Fix that first. Use the stock plastic parts, plus seal up all the gaps with a foam rubber and plastic sheet.

 

Thats why i was asking i was wondering if the ducting still wouldn't do it with a stock radiator that way i could order a koyo now and have it get here by the time i finish making my ducting. I am making my own since i dont have stock pieces and building ducts around the side and top and bottom of Greddy FMIC.

 

the under belly pan is absolutely essential for air to enter the radiator. The radiator is installed at an angle so all the air goes right under it instead of thru it without the duct. Duct it and seal it, then you should be good.

 

You will need to replace the underbelly pan, and run proper ducting to the rad. I have seen this problem before with the exact same IC you have. Best to run a duct to the oil cooler, and one to the rad. You need to direct all airflow and prevent it from wrapping around the oil cooler or rad.