titleistaddict87

Anyone done it? I'm guessing this is only really necessary for hot climates and/or track use, but I'm just curious who's done it and what the experience has been. I like the idea of keeping things cool but is there such a thing as "too cool". I also like the look of a third radiator and center grille opening (mine currently has the hard plastic center), but I suppose an easy solution is to just remove the center plastic and replace with mesh grilles.

Comments?

CSK 911 C4S

http://www.suncoastparts.com/product/9913RD.html

It's not a bad little upgrade. Pretty much plug and play. Having had the bumper off my car I could actually see where everything connects and that might be over simplifying but it looked like it was all pre plumbed to make adding the center rad pretty straight forward.

Just adding the center screen without the center rad air ducting would just create a pretty large air pocket doing nothing positive for the cars aerodynamics.

R_Rated

I'm considering it. Even in traffic right now the car gets hot. have Rennline mesh in a box waiting for the bumper to come off.

STG

+1 EXACTLY

I added it. No downside at all except better looks and better temps.

Suncoast sells the whole package with all the trim pieces too. Already plumbed. Just install, but you need to add some coolant and burp the system after install. Maybe leave to a dealer for ease.

I would NOT just add mesh there and have flowing into your bumper. Not a good idea.

RobC4sX51

If I tracked a lot I would do this mod too. Power kit (GTS) cars it is standard too. But personally I don't like the look and it opens the can of worms for even more radiator puncture holes and the need for mesh screen, even more so since it is front & center. The 997.2 w PDK at least channeled the air from the center plastic piece into the side radiators with openings on each side! Why the 991 does not have this is strange to me. On another note, as has been mentioned here on RL before, driving in sport (or sport plus mode w sport chrono) will lower your oil temp about 10% as it opens additional cooling for the oil system. I know we are talking water (coolant) temp but oil temp is much more important IMHO!

titleistaddict87

Can someone educate me (and anyone else who doesn't know), what's the optimum or target operating temperatures for oil and coolant on our cars? What kinds of temp differences are you seeing before and after this mod?

LexVan

My car has the center radiator, since it's a PowerKit car. My temps don't seem to be any different than any of the other 991s on this site. And since our coolant gauge taps out (stops reporting) at 194, we don't really know the true coolant temps.

The big difference is standard mode vs Sport Plus. There, we'll see lower oil temps by about 30 degrees (195 vs 225 and higher).

For optimum gas mileage (2-4 mpg higher) the car likes Sport Plus mode off and oil temps in the 225 range.

*all street driving, you'll get different answers for track use

997s07

The third radiator won't change operating temperatures. The car has the thermostats programmed for the optimum temperatures. What the third radiator does, however, is increase cooling capacity. So for cars producing relatively more heat or for cars in very warm environments the third radiator provides more surface area to cool the coolant.

titleistaddict87

Super helpful information. Thanks. Summer here reaches low triple digits on a regular basis so sounds like it would be helpful for days like that and not really harmful in anyway other than to the pocket book, but with these cars, what if anything doesn't hit the wallet?? hahaha.

R_Rated

A must have for the inferior 991.2 when it comes out. Cooling is paramount with boost.

997s07

Hmm, you mean an intercooler? I think those are located in the engine bay for the 991.2. There are airflow slats located in the lower side sections of the rear bumper. Certainly a must have for an 'inferior car.'

R_Rated

Cooling period. Hard to read intent or tone but I know where the intercoolers sit on the new car and the difference between and intercooler and a radiator.

Here's something I fabricated in a previous life...

997s07

Why so angry...

bossboy302

I'm still trying to confirm (or not) any operating temp changes after 3rd radiator install.
I might disagree with the above, insofar as thermostats do regulate the minimum coolant temp, but certainly not the maximum.
With the 991 temp indicator set to read a max. temp of 194, how does one really know what the water temp might actually be.
So, even when reading 194, actual coolant temp could be 220-230...more?
Could the 3rd radiator reduce that temp, for example, from 230 to 200, even though we still see 194?
Thx

Valvefloat991

I used the Torque app to look at the actual sensor readings and while the water temp gauge essentially freezes at 194 degrees, the engine is actually operating at about 220 degrees in normal driving on a 50-degree day. The oil temperature gauge seems much closer to reality, though it also seems to start getting sticky around 225 degrees. Haven't checked this at a track day yet, but will do so in the summer.

And there is one down side to the third radiator--extra weight. I don't know how much it is, but it's probably 10-20 pounds.