Lol no it wasn't keeping up. In Any of my cars. Ambient today will be 103. It's over 100 every day for about three months.
I am doing a radiator in my Miata today and just ordered one for my 64 dart. They were all either borderline or not setup correctly.
On the defender I had the copper three row radiator, I bought it because it was heavy duty and essentially they last forever. Unfortunately with my front mount intercooler, custom grill, and RevoTech fan it just wasn't getting the job done.
Ended up repositioning my intercooler, adding foam to the RevoTech fan to seal it directly to the radiator core, replacing the copper radiator with a Chinese aluminum one, and removing my front grill. Now I can drive when it's over a hundred at highway speed at full boost without the temp gauge creeping up to 220.
My real issue in the defender is that I'm anywhere between 25 and 30 lb of boost at highway speed. This creates a ton of heat in the intercooler and I'm preheating the air above ambient by the time it actually gets to the radiator. The other downside to my setup is that I have a liquid cooled turbo and this dumps a ton of heat into the coolant path.
The Miata the car has some body damage on the front hood so we run a bra to cover it up. The bra also blocks air coming into the radiator. The stock radiator in the '99 Miata is a single core and is only about 3/4 of an inch wide. So I'm moving that to a three-row aluminum thankfully they're very inexpensive. I'll probably be removing the bra as well.
The 64 darts radiator is original and just got us by when we lived in California. I've patched it a few times and the car runs cool even without a fan shroud (factory) but I know that it'll blow up if we take it on a long trip. When I drove it here from San Jose I drove overnight to avoid daytime temperatures and it made it here without an issue. That again will probably get a new radiator and I'll build a fan shroud for it.
We also tinted the 99 Miata so the air conditioning can keep up in such a small car. I didn't expect to have to do all this work thank goodness that I can do the work myself and that the parts aren't exceedingly expensive. Thank you china.