New rad + ac, overheating ?
 

Hey,

Just installed a new Mishimoto rad in my 97 NA, the old stock rad could not hold boosting with ac on I would see temps up to 240F (115C) and then I would turn off the ac.

Even when driving hard with the stock rad and no ac, it would still overheat.

On the trip home with the new rad I noticed that it would still heat up with ac and boosting but much slower, I got up to 212F (100C).

There is still space between the rad and the body, and there is space between the right fan and the rad.

No coolant is missing.
The fans run together.
Fans turn on @ 194F(90C) and off @ 188F(87C).
Ambient @ 86F(30C)
Got IC.

I'm good ?

Thanks

https://www.miataturbo.net/attachmen...ine=1379538148

212 is OK.

A coolant reroute would have made a bigger difference and remains a good idea.

most important thing you didn't mention: shrouding

No shroud, stock fans.

Reroute as an addition right? Not instead of a rad upgrade ?

/thread

Aren't the stock fans on a shroud? They were on my MSM, at least.

No, just bolted to the rad

What Vlad said (assuming that by no shroud you mean that you've removed or cut big, unsealed holes in the air guide/undertray).

More than likely, had you had decent ducting you would have been fine even with the OEM radiator.

Bigger radiator doesn't hurt anything and a reroute does great things to even out engine temperatures and increase water flow to the radiator (at the expense of water flow to the heater core).

My car is 100% OEM cooling system with ducting in like-new condition and a reroute. I'm cool as a cucumber in 100+ -- including idling in traffic with AC and track days. I do turn the wick down to 5psi for track days though.

Ah ok.

Well... i wouldn't be worried about those temps. :)

100+C is ok?

I idle @ 90-93C traffic with AC on.

I boost 10-12psi

The stock rad was 3 years old, no way it would hold boost+AC when is is over 30C out side, even without AC it would over hear.

Well you just said 212F is what you hit. 212F isn't scary.

a radiator doesn't hold boost.
and your issue is lack of airflow that is generated by lack of shrouding (and from your description lack of fan shrouds too)

a 3 year old radiator is actually fairly new

When I said 100+, I meant it was 40C+ outside. MERICUH!!

What is the red line temp ?
At what temp should I set the fans to start?

The rad does not hold boost, but what I mean is that it does not handle the heat @ long boost.

yes it does. over half the people on this site are running the stock radiator which is way way older than 3 years

I'm not sure what you mean by "red line temp."

I have my fans set progressively. First one on at 195F, second at 210F or when A/C is on, whichever comes first. Off at 185.

With ac? I find it hard to believe.
The AC condenser is all over the rad.
I know people remove the AC system, then it would be more reasonable.

Until this past May, my car had the original factory radiator in it. Cooled just fine despite being 9 years old.

I only replaced it because the tanks were getting green, which is a bad sign.

:facepalm:

He is literally trying as hard as possible to be in denial and fix everything except the problem.

We need pics, please provide

You list temperatures in C horsepower as wbhp and 95RON for fuel, so I'm guessing you are in Europe. What you call a shroud we may call something else.

If you removed this thing from your car, put it back on:

https://www.miataturbo.net/attachmen...ine=1379543901