Setup: Greddy FMIC, Koyo rad, GT3582R 15-20psi, fuel mods, duel 16row oil coolers, 65c thermostat.

OK the rad is seal off on the side top & bottom but set upright behind the greddy FMIC. Air temps are 22c water injection assisted, water temps are going over 104c after 4 laps. Leave pits on 85c. Cools down quickly after 1lap of slow speed it comes back down to 88c

Iv searched for people with a similer setup & the same problem, cant find any.

On the street it never goes past 86c even in traffic.

What should I do?
Take out the thermostat to get better water flow?
Change to V-mount?

 

Ditch the FMIC

 

is the rad and intercooler ducted in at all?

 

Well the IC sits way out front as the Greddy ones do and then the rad is inside the engine bay. I have stoped air from going around the rad so its seald top bottom & sides. There are some small gaps on the sides of the IC so the air can spill over to the Rad. I dont have an air temp problem.

I need an Oil temp gauge so I can see whats going on with that side of things.
Do you think I need to put some plates on each side joining the back of the IC to the front of the Rad & sealing off the space inbetween?


In the pic I have removed the top rad cover so yo can see its position.

 

Disagree. Just make sure everything is well ducted and the air isnt escaping. Remember air will move along the path of least resistance, so anywhere that there is a hole it's going to escape and not get forced through the radiator. I see in your pic that theres no blockoff at all on the top of your radiator, that would be a good start. It's incredible what ducting alone can do.

I have an FMIC and a gigantic oil cooler sitting in front of my radiator, and it's a 3rotor, and I don't see water temps above 215* and oil temps over 205*.

 

Which FMIC are you using? The reason I ask is that the Greddy FMIC's seem to take up the most frontal area on the FD. I've seen a few guys have heat issues with the Greddy where as similar setups using something like a Blitz, Apexi or smaller custom Spearco setups don't have the same issues.

 

I'm actually on an FC chassis, but I'm using an eBay 32x12x3" intercooler. It's gigantic and basically obstructs the entire front of the car. I'm guessing given that it cost $80 it doesn't flow particularly well either

 

Depending on what front bumper you are using, you may have more airflow coming in overall. It's hard to compare the amount of air getting past the FMIC between different front bumpers let alone different car models.

 

Not a great pic, but you get the idea:

 

Ah, where's that duct go to above the IC?

 

Straight to the radiator/oil cooler; there is a sheetmetal divider so the air entering into the upper opening doesn't go down to the FMIC. I'll take a pic with the bumper off tonight so you can get an idea of how it works.

Additionally plugging the thermostat (or gutting a thermostat) is, imo, a must-do on a track car along with an underdrive waterpump pulley.

 

Yes, that's what I was talking about. FEED did that on some of their bumpers to help out the flow for FMIC setups however his nose does not have that. So his entire airflow is through the FMIC where as you also have direct air to your radiator/oil cooler:

https://www.rx7club.com/attachment.p...2&d=1196923541

That's a big difference in airflow for cooling.

 

Thanks for all the input guys. Greatly appreciated.

I removed to top cover on the Rad so you could see the setup in the pic I posted earlier.

My Feed bumper used to have that little hole in the top like most do but I had it removed by increasing the size of the main hole. AS you can see from the new pics Iv added that my FMIC is so large that it covers the entier front section.

Iv been thinking that due to the gap between the 2 that the air pressure at high speed seems to drop as the air passes through the IC area it opens out to a larger area behinde before passing through the Rad. Now the Rad itself is sealed closed on the sides, bottom & top when the cover is on. I think that I need to fabricate some panels to box in the rad behinde the IC so the air speed & pressure is kept & forced through the Rad.

I have the undertray all setup & it has small sides on it but I think some large alloy panels to decrease the size of the middle gap & keep the air funneled towards the Rad.

The whole black area is the IC.

 

IMO, I would change FMIC's to something a little smaller if you are serious about road racing. Even with ducting the radiator to the FMIC, the airflow velocity is still reduced since it has to travel through the FMIC first; therefore reducing the effectiveness of your radiator. Add in that you have a Koyo which is really thick and you have one huge heat sink in the front.

Or, you could always sell your front bumper, go back to an original FEED and duct the opening straight to the radiator like it should be.

 

Some good advice there but I dont think an original feed pumper would help as that little duct is also blocked by the IC due to it being so tall.

I have seen some japanes track cars with similar setups, I wonder how they deal with it? Dose anyone recomend taking out the thermostat to get max water flow?

 

IMO, that's not going to help this situation. Removing the thermostat will remove the restriction which allows the coolant to stay in the radiator long enough to remove heat from it. Speeding up your coolant flow will have the coolant spending "less" time in your radiator which can cause less heat removal.

 

Haaa true that. Well then I guess I will endevor to try some other things.

 

Is there any way to route air over the top of the IC?

 

Nope dont think so. May be able to from under the IC or the sides but I think it goes to high up to get anything good out of it. There is a nice gap under the Ic between the undertray and the bottom of the IC. I could perhaps build a scoop that sits bleow the ic to catch air and throw it up infront of the Rad.

Thinking about this I came up with and idea. What If I fabricated a vent in the undertray with mesh to stop debries but let fresh cold air into the gap between the IC & Rad? Cut a rectangular hole with a scoop plastic welded into it. Put some mesh in and duct it into the Rad. I have enough clearance under the car for something like this.

Here look at the clearance I have.

 

Errr scratch that idea, I forgot that there will be vacuum under the car causing the air to be sucked out.

 

The old TurboFighter FMIC (IIRC that was the name) used a scoop under the FMIC to bring fresh air directly to the radiator. I don't know exactly how effective it was, but it was one of the more sought after FMIC's when it was around (7-8 years ago).

 

Hey thanks, thats nice to know my idea has been done before. Perhaps I should give it a try. Who knows, could be a winner.

 

IMO, you don't have much to loose but your time. It's not going to make your cooling worse.

 

Yes very true. Just time. Ill have to figure out how to make the intake. Not much space to work with. About 2-3inch in width and hight of the gap.

 

The heat issue wouldant be caused by my Scoot hood would it?
I dont have an original scoot hood as you can see the front scoop is not ducted through to the rear of the engine bay like the originals do.

Mine is fully open. I closed it off for some testing to see if it was creating a high pressure area over the rad & stopping the air from coming out.

Seems to have helped a little. Not sure if it still playing a part in the heat issue. Perhaps I should try a stock hood.