So i learned recently that I do not have the stock undertray for my 1987 FC.
From what I understand it is meant to redirect airflow to my radiator and aid in dissapating heat from my coolant.


Soooo is this going to make a significant difference?
I would like to know because my FC is running a little too hot (1/2 to almost 3/4)
Please let me know thanks guys!!!!

 

It does make a difference, but 1/2 to 3/4 seems like a lot. does this happen while on the highway, or in stop and go traffic?

 

yup def makes a difference , it least on my fd it did , my coolant temps dropped almost 20' on the highway the first day , stop and go traffic is tough with or without one since there isnt much air flow going on.

 

If your not running an aftermarket radiator I'd get one,
I brought a brand new stock rad because I had the
Same problem, I tried the undercarage tray I think it
Helped a little,but as soon as I brought a bigger rad
The problem went away. Now instead of running at
Half temp gauge, it's running nice an cool on a 1/4.

 

Are you sure that your clutch fan is still good? A bad one will definitely cause overheating.

 

If the fan is bad then it will overheat at idle but be perfectly fine at speed.

 

the undertray does make a difference but it is an end of the road problem, meaning if you are having overheating issues(which you are) it will not solve them. it does aid in cooling both in traffic and on the freeway allowing the fan to do less work.

basically you need to check out your cooling system thoroughly first. check the thermostat, pressure test the cooling system, inspect the radiator for blockages inside and out, check the fan for free wheeling and be sure the cooling system is free of air and builds and holds pressure appropriately.

you will eventually need to address the lack of undertray but i would focus on the rest first. making an aluminum undertray has been on my list forever, partly because 1/2 the FCs i come across are missing them.

 

aftermarket radiator, pressure test the coolant system.

awesome thanks guys.

 

i installed electric fans. two 10" fans at 80watts a piece....just an fyi
it ran cooler with the fans but still gets warm

 

I found that without the under cover installed the front end did not feel as stable on the highway. This was at 80+ mph. After reinstalling the cover (drilling out the broken bolts and re-tapping the bolt holes!) There was a large improvement in the feel of the car at high speed, it seemed less turbulence was under the front part. Aerodynamics?​​