Boost Lee

iTrader: (3)

Ok guys, I suspect many of you have had the same issues in the past and I need to know how you've resolved it.

Over the past few years, I seem to have always had an issue with overheating in my FC. Whether it's Rotary powered or piston powered, there's always a heat issue going on. My current setup is a Nissan Ca18Det in the FC. The stock bumper is in place and there's a bar/plate intercooler filling it up. There is nothing between the intercooler and the radiator except for the power steering line and the OE support structure. I've built a box out of ABS plastic that basically connects the back of the intercooler to the front face of the radiator. No air escapes!!!!

At my last track day, I managed to get up to 210F which is way warmer than I'd like to be running. I've got a 160F thermostat (not that it matters once everything is hot).

Here are the questions I've got for y'all.

Did anyone notice a difference when switching from a bar / plate setup to a Tube/Fin?
How much of an impact did/does a drop vent in the hood have?
Which radiator(s) are you using / made a difference?

Thanks

nofords

iTrader: (9)

1) Lots. We dropped 30deg water temps in our race car by adding a vent in the hood. we had to put a thermostat back in.

2) I am using an ebay knockoff aluminum rad with a single 17" fan

In your ducting, it might be wise to duct some fresh air between the intercooler and rad.

But in all honesty, the key is to re-arrange your rad setup. I had no more cooling issues when i went to a modified "v" setup on my race car. FMIC just block too much air.

Make sure you have three 3/16" holes in that thermostat. Should it fail due to overheating, you will loose all coolant flow.

Valkyrie

Cut a hole in the bumper for the intercooler.

Get a vented hood.

Lift the hood hinges to let a little air out the back. I think spacers or a kit of some sort can do this.

Are you using a stock radiator? Upgrade to...anything you can afford, really... as long as it's bigger.

What coolant are you using?

RockLobster

iTrader: (7)

Dump the FMIC...go v-mount.

I always take crap for saying this but a TMIC is better than a FMIC for a road course FC.

BLUE TII

iTrader: (9)

I have horizontal mount and love it, but FMIC can work.

The real problem with most the FMIC in the FC/FD is they put the intercooler way in the front of the bumper so there is a huge gap between the intercooler and radiator.

The proper way to run stacked heat exchangers is to have them right up against each other so it is easier for air to penetrate the cores. Look at any oem set up and the majority of FMIC cars.

The gap between FMIC and radiator causes air to slow and become turbulent after exiting the FMIC and it is really hard to get it to penetrate the radiator and oil cooler cores.

Additionally, having the the FMIC right in the front of the bumper causes air to hit the face of the FMIC, meet the resistance of the core and flow off the side with the rest of the air going around the bumper instead.

It is advantageous to have a slightly smaller duct opening with some length of duct before the heat exchanger(s) so when air enters it takes more energy for it to flow back out of the duct than penetrate the core(s).

This isn't new knowledge, its the way heat exchangers are done over and over anytime packaging allows.

Boost Lee

iTrader: (3)

I'm running distilled water for coolant, with a little water wetter just to be sure.

Last weekend I ran with the vent in the picture below. My temps stayed below 190 for quite some time but eventually climbed up to 200+ again. Before I decided to try a V-mount setup, I may try a different radiator first. Any recommendations?