speedz06

Hi All, as many know I have been struggling with traffic (A/C on) overheating issues for at least a year on a near daily driver Eforce custom tuned 2006 Z06.

I have tried everything except for changing the timing at idle since I'm really not sure about it AND I'm not sure if idle timing is the only culprit since I am often at light throttle in traffic conditions. I don't think the car will actually overheat just idling with a/c on as much as it overheats in the stop and go, manhattan NY style traffic.

Many others have this issue, not only me.


A question I have also is just when does the cooling fan shut down?

If my cooling fan shuts down at 5 mph then that is good reason for overheating and also, is there any adjustability in the time or speeds the fan shuts off? Maybe a crappy tuner got hold of the settings and made it so my fans cut off too early. OK: Manhattan, NY traffic is brutal to any car, any engine. Even light traffic makes for a cooling system challenge.
Note that the car runs fine on highway and speeds over, say, 30mph or so.

I am considering this question. IN TRAFFIC will an OEM radiator outperform the aftermarket "high performance radiators such as the dewitts I currently have?)

I am running the D3 fans but may change to the single 600Watt GM Performance parts brushless 17" fan. with a custom shroud.

Will the C6 ZR1 radiator outperform the OEM Z06 radiator?

Theory: IF (in general) a thinner OEM radiator will allow more air to pass through it and shed more heat faster, if the C6 ZR1 OEM radiator is perhaps a bit higher capacity BUT thinner than the Dewitts, I think this could be a help in the stop and go traffic.

The Dewitts higher capacity is immediately noticeable and appreciated however peak overheating temps oover 245 degrees still come on, only much slower. With the Dewitts, I was able to put off the overheating for up to 45 mins. Plenty of time for most Vette drivers to get out of traffic and never notice any issues with their car.

This leads me to think that the ability to decrease temperatures is proportionate: The coolant is slower to cool down because higher capacity but more importantly, I am thinking that the thicker, dual core will not allow air to pass as easily, also air speed from fans is slowed more than the thinner radiator. Even less air reaches the condenser.

I have only seen a few images of the C6 ZR1 radiator but wondering if anyone actually tried the two on a C6 or C6 Z06 and what is involved but more importantly, the results. Maybe this is a happy medium?

I am considering trying the radiator lowering bracket and having a custom built radiator made with extra capacity (taller) along with a tightly shrouded and sealed larger fan to match the larger radiator, while keeping the oem or similar thickness.

Taking out, relocating the trans cooler that the OEM C6 Z06 has will also increase capacity and reduce heat.

I hate to remove the Dewitts and try either OEM or the ZR1 without doing any research hence I put this out there.
The Eforce installation really should not have much effect on the cooling system. I have the front plastic air directors removed so the air does not have to go through the HX at low speeds.

If I can just get away with going back to OEM or ZR1 radiator with a stout fan setup would be great. Maybe the thicker radiators are good for everything except spirited and bumper bumper city traffic.
All cities have traffic but I think NYC driving style and terrain is most hard on vehicles.

If anyone has actually tried going back to OEM style radiator after having the high performance versions I'd like to know the results.

Thanks

Dano523

Not knowing that you did on the tune with the Eforce super charger, would bank that you just turned it into a heat pump by over spinning it instead.

So make sure that your E force heat exchanger raditor is not blocking the motor raditor flow itself, add some water wetter into the Eforce radiator water to help it better cool the boost going through it, and install a Meth kit into the car to help combat the Eforce becoming a heat pump during boost/loosing power on consecutive boost as well.

As for the E force Tvs-2300, it good up to about 650hp, then where you are pushing the HP beyond that with more boost pressure, it really too small of a unit isntead. The problem is Easton does not make a TVS-2600 yet, that would solve the problem instead.

irok

the ZR1 radiator is larger,single core and has no side tanks.should help cooling issues some.price for it is

R_W

I would think (per your theory) that having a thinner radiator decreases surface area front-to-back, as well as decreases capacity within the radiator itself, thus resulting in worse cooling...
I run a Dewitts Rad (ONLY, no trans / diff cooler in radiator, those are stand alone) in my LS3 GS track car, and have had great results. Then again, I blocked off all air escape paths before entering the radiator and have extractors and vents behind the fan/rad in the bay to help suck the hot air out and the air through the radiator itself. That's just my situation, though. Yours may be a bit more complicated w/the blower involved...

jim2092

might help

https://www.corvetteforum.com/forums...d-control.html

sccaGT1racer

You should start looking at something custom from a real radiator company like fluidyne ,ron davis,or C&R. It will cost 2000-2500 and will fix your problem. Is your supercharger intercooler in front of all the other coolers? You may have to duct the heat away with separate ducting.

nuke61

That bolded part tells me that your radiator situation is fine, it's the fans that need to be addressed. I don't know what the C6 fan setup is, because I haven't looked at it with HPTuners since buying a C6 to replace my C5, but I'll tell you my experience with the C5.

It was a C5Z, with a forged 402 ci (6.6L) shortblock, running a max of 10 lbs of boost (600whp/600wtq), with a DeWitts radiator. Coolant temperatures were always good, even in stop/go traffic on the Las Vegas strip, and in stop/go traffic in Phoenix - both in the summer, where temperatures can and do reach 115 F on a regular basis.

The fact that your coolant temperatures are fine with speeds over ~30 mph tells me your issue can be fixed by going into the ECU and changing the fan settings.

nuke61

I did a quick look and the C6 radiator fan control is very different than the C5 control. The C5 ECU settings allowed you to control 1 or both fans, on and off temperatures. No so with the C6, since it has a single large fan and a PWM controller.

The following is the fan settings for a stock LS7. My tuner, NicD, basically shifted all the Fan Desired settings two positions to the left, so at 192.2. the fans are running at 15% of full speed.

As far as I can tell, unless there's hidden stuff that HPTuners cannot see, there's no turnoff at less than XX mph. In fact, your fans should run after you turn the motor off if the coolant is hot enough.

double06

The D3s and the Dewitts should work. I think like people said check the % of power fan settings, timing, but also the is it running lean at idle which can also make a lot of heat. Maybe also make sure both fans are operating instead of just one. The over 30 comment would lead you to believe it is a air flow issue and/or idle tuning issue.

mikeCsix

I recall reading somewhere on the forum that the fans aren't needed about about 35 - 40mph and turn off.

DeWitts also makes a dual fan system, but it creates a bit of an electrical issue.

If your thinner fan hypotheses works, then why does my DeWitts at twice the depth, handle heat on a racetrack so much better even with an and added EOC?

speedz06

yeah I think you are correct.
If I build a radiator specifically for the car it will be costly but then again the only option. Some guys have no issues but dont get into my type of driving

speedz06

I think the fans just cant perform like a moving vehicle no matter what the manufacturers do. I have been thinking a thinner core will shed heat faster at low speeds when only the fan is providing airflow but likely not do as well in WOT high speed situations.

speedz06

ok, so it is solely temperature controlled...even if im doing 60mph then the fans will kick on if temps warrant it. I just wanted to confirm this.
i actually realized there was a big gap between the radiator and shroud on the top. I sealed this and too early to tell but after one ride it seems to be helping.

nuke61

Yes, unlike the C5, they don't positively turn off above a certain speed. They will run at variable speeds, based on several inputs. Here are all the things that will turn them on:

• high water temperature, of course
• high A/C system pressure
• high oil temperature
• high transmission temperature

If coolant temperature or A/C pressure is high, they will continue to run at a lower speed, after you shut the car off, until it cools down.

Yes, make sure your shroud is well sealed. You want all the air to be pulled through the radiator. Again, the fact that at ~30 mph your engine stays cool means that the radiator is working. It's your fans that need to be looked at.

I have a H/C/I/E Z06 that puts down ~575 whp, also with a DeWitts radiator, and it stays cool here in Phoenix in summertime stop/go traffic - and I'll bet it's far hotter here than where you live - or nearly anyone on this board, for that matter.