speedz06

so..Still messing with overheating with a/c on. Only with a/c, only in traffic, no other time.

The eforce z is cool at 170's in the morning air on the highway, 190's to 200's on a 90 degree day in Manhattan traffic...
Then with A/C on the temps steadily climb to 230..240's until I'm forced to shut off the a/c.

I mean, we cant let it get into the 150's right? Anyone run into the 140's often and just let it stay there?

There's a decent enough fan from the D3 kit to pull air through the Dewitts
and I can place a piece of paper on the condenser and the fans hold it sucked on, there is decent flow.

Condenser is new, radiator clean.

The Dewitts has the brackets like oem and the condenser is nearly touching the radiator.

I even put two little spal 7.5"pusher fans on the front of my heat exchanger (eforce heat exchanger is restrictive btw when I compared to the D3 HX Im about to put on soon)

So, if the car runs cool on highway but overheats in traffic with a/c on doesnt it have to be either not enough fan or I hate to put this out there but what if the Dewitts being thicker is hindering airflow to the condenser? Even the upgraded fans cant pull the air?

Id like to try an oem rad with the D3 fans or a thinner Dewitts which might be available. That is work and money for a gamble that might not pay off.


So much time, work and money but still cant get the high temps down in traffic with a/c on.
Hence, cant cruise in Summer or even commute and really enjoy.

I pulled the flexible rubber flap from behind the bumper to make sure the HX wasnt restricting air. There is a 3" gap min from the condenser to the HX anyway and plenty of gaps for air to go around.

Anything?

russ472

kinda have the opposite problem. I have no issues running hot. stock radiator and fan (spliced the fan wires and running at 95%. on extremely hot days in traffic, my ac head pressure gets too high and it turns the compressor off. I have thought about reducing my freon level to compensate.

your thicker radiator may be causing an issue with airflow restriction. Unreal had some overheating issues after installing a thicker intercooler.

Unreal

Thicker intercooler that was 2x the size of the ecs one, so that makes sense.

Something is wrong with the OPs car. Idle timing, something.

Josh@AandASuperchargers

I had to reduce the Freon level on every C6 I ever installed headers on when I had my shop in TX. It's a easy way to get the high side pressure to come down, and the a/c still blows nice and cold.

Unreal

Agreed with Josh. Never seen a c6 from factory with AC filled correctly. Was just talking about this with a local last Saturday. Had to ditch some freon, as it was overfilled, and now his AC works perfect all the time.

schpenxel

Interesting, had not heard that before

speedz06

Im wondering could the condenser be getting too hot?
Is it the freon level that will govern how hot the condenser will get?

I just cant see how this thing runs so hot. Today I wanted to see if it would level off but no...up to 250 then I shut off a/c while still in traffic and temps went down to 220 reasonably quickly.
I havent adjusted timing yet but it was suggested. The tune has timing set differently at different rpm's so I guess I could just shade the whole idle table and add +2 or something.

The shop that built and reinstalled the motor was terrible but I cant think of what they could have done besides leaving an onstruction in cooling passage.

My c5 ran just fine with magcharger, dewitts and meziere for more than 100k miles never an issue and that car was beat on.

schpenxel

What's it actually seeing timing wise at idle?

heiseyqueen

What could it be in a 2003 z06 that the high speed fan doesn't come on ! Tried a new thermostat, only does it in traffic not on the freeways but my can will heat to 230-240 I'm afraid to drive it

schpenxel

Is it a separate relay and or fuse for high/low? I haven't looked at how they're wired up. I'd look for something like that first

02FireHawk555

I brought the same question up on the forced induction forms on facebook and the answer seemed to be that the air needs to be forced back through the radiator by fabricating a piece of sheet metal to block air from escaping over the top of the radiator and onto the engine. Also recommended was installing a dewits dual fan set up. Pics aren't the best but that's all I got from my thread on the subject.

Unreal

For idle, disagree on needing to "force air" through radiator. Shrouds work great when moving and using the outside air, at idle they make very little to no difference. Dewitts dual fans depending on which ones can be a big downgrade over stock.

He already has crazy fans. Something else is wrong.

realcanuk

Something odd for sure.... Ran the eforce at many levels including maxed out and never had temps much over stock... even with stock rad and fans. Then eforce IC is small and doesn't interfere much with cooling.

Detoxx03

Crazy stuff. I just drove my car from Louisiana to Michigan yesterday and got stuck in traffic a few times with AC on and it never went over 208. It was 95-98 the whole trip too. This is stock radiator that was sealed with weather stripping.

schpenxel

What fans are you running?

Detoxx03

Stock fan

speedz06

I'm working on this more today.

FYI, this is a newly built LS7 all oem except for forged pistons. The tune was a mess. The shop were butchers although the guy is an old school engine builder. I hope it holds together.

Overheated with a/c on in traffic from the day I got it from he shop.

found that although I had a fresh engine that the installer left my dirty radiator and condenser clogged with tar and feathers (literally)

Figured i found the issue and just bought a dewitts and D3 fans. (D3 guys told me not to go with thicker radiator but I had good experience before with dewitts so didnt listen.)

cleaned condenser but a/c would cut off when hot.

Replaced condenser, moved out the oil cooler and went to water/oil cooler supplied with eforce kit (oil temps went up 25 to 30 degrees compared to oem z06 cooler)
Now the a/c kicks *** and still works even when engine is screaming hot.

took about 40 minutes longer after deweitts but STILL overheated with a/c on. I credit that to the increased capacity.

meziere water pump...lowered temps a little but problem still exists, will still go up past 250 degrees and never stabilize on hot day in traffic.

spent thousands and lots of time.

Thats the history.



A better known tuner worked on it for long time, several dyno runs and got the WOT, midrange and top end pretty good It can use a few tweaks but the car runs as daily driver.
He did very little down low...Idle wasnt great though and I'm too busy to keep going back there. I went back once and he did minimal again so no sense in going in circles.

I wish that I could just put an oem radiator on and see what happens. Why the car runs at 180 degrees on highway cruising in hot weather but so hot at idle? Just airflow? but since timing and fuel have their separate adjustments for idle I'm concerned about that.

The guy that originally tuned it made such a mess I feel that he screwed something up somewhere. He said he was "deep into that stuff" and said something about "eliminating the cold start stuff" because it had such a bad surge when he gave it back to me especially cold mornings. This was with the oem cam.


Is there a factory tune parameter guide so I can compare?
Does an eforce on an oem engine even require any changes to idle tuning?

Idle spark/AFR?

airflow? both?

I have saved some of the idle spark and fuel tables this morning and will work on the car today to see what i can find, following the book going through the steps, maybe im missing something.

the full tune should be there as well.


I'll post the screenshots and idle spark advance
im adding a log just putting around the city but at 226 degrees its before the car is really hot.

realcanuk

The addition of the eforce definitely requires tune changes to airflow and idle parameters. I assume the injectors were changed also.
That shouldn't have anything to do with your temperature problems. Don't spend time and money changing the rad out again. It should be fine with the dewitts, especially with those fans. Something else is going on. I remember reading about an overcharged AC system causing high temps.... maybe check into that.

russ472

maybe try bumping your idle timing up 5 degrees and see if that help any

schpenxel

Idle timing is totally stock at around 13*. I'd agree.. bump it 5 or 7* and see if it changes anything.

Actually--ALL the idle settings are the same except the top half of the min airflow table and the idle RPM (set to 1,000)

I would also turn that knock decay rate back down. It's around 20x the stock value.

And lastly, looks like PE table is raped a bit, it's commanding almost 14:1 @ WOT at 3,750 RPM's. Not the right way to do it

Ok one more. Looks like he's turned the SES light off for a lot of stuff. MAP sensor, etc. Again, not very reassuring