Wondering if I can get some advice .
I have a C5 with D1SC Procharger ,forged and stroked to 383 .
heavy duty aluminium radiator with built in engine oil cooler.
First hot day and it overheated . The state I live in can have extremely hot weather.Fans are working okay , high quality coolant etc.
Any suggestions ? Should I disconnect oil cooler lines and run external oil cooler. I have the Procharger intercoolers so air flow to radiator is not obstructed but I wonder if the changed angle of the radiator is contributing to the problem .The radiator is angled further back due to the new Procharger cradle.
Would removing some heat from the engine bay help . Perhaps better airflow through radiator and out through some vents???
Any advice or thoughts would be greatly appreciated .
Thanks in advance . Peter ...Australia

 

How old is the thermostat?

 

Thermostat is new...but that doesn't mean it is functioning properly.

I will have a look at it.

 

What do you mean when you say the car is "overheating" ???

The LSx engines are designed by GM Powertrain to run much "hotter" than a lot of people expect. From the Service Manual about the cooling fans ...

The low speed cooling fan is commanded on when the coolant temperature reaches 108°C (226°F). It is turned off if the coolant temperature lowers to 104°C (219°F). The high speed cooling fan is commanded on when the coolant temperature reaches 113°C (235°F). It is turned off if the coolant temperature lowers to 108°C (226°F). When the A/C is on and the coolant temperature reaches 85°C (185°F), the low speed cooling fan will be turned on at vehicle speeds less than 56 kPh (35 mph).

Also, unless you have modified the PCM programming, the car has a built in "Engine Over-Temp Protection Mode". You can read about it in your Owner's Manual.

 

If you don't have a shroud sealing all sides of the radiator and forcing all air to go through and not around, you should. If it's overheating when just driving normal then you should confirm radiator and the AC condensor is clean of debris.

Arnel

 

Car is certainly overheating as when I stopped coolant was boiling out of overflow tank.

I will look at air flow and seal off any air gaps around radiator .
I will also disconnect oil coler lines from radiator and connect external oil cooler. I never really liked the idea of using the radiator to cool the engine oil .It must be putting a lot of heat back into the cooling system.

 

AVB THAT IS ONE WILD LOOKING ENGINE BAY.....
WHAT RADIATOR ARE YOU RUNNING AND HAVE YOU HAD ANY COOLING PROBLEMS?

 

Check you radiator for dirt, grass, plastic bags, or dead wallabies. Take a high pressure air hose or water hose and spay out those radiators.

It does not take much dirt or sand to block up the radiators.

 

Make sure your pressure cap is good on overflow tank. If it leaks you will boil over at about 212 F. What temperature are you boiling over at?

 

I have a stock (sans exaust & a K&N) '98. I was realising temps of 235 on a daily basis for the past four months. I read quite a few threads in the forum with the ususal answer being "Our cars run hot; the fans come on at.....) Bull&*^%. My waterpump was on the fritz with absolutely no indication. I had it replaced and now I'm 201 in Texas.

 

Thanks


I've had my share The good thing is, you shouldn't have as hard a time as I have.

As for the shroud... without one, if I pushed hard and tried to keep it under load, it would get hot enough to back off. If it were 110* plus ambient, it would sit at 220 and never lower. Again, in the streets.

Once I got the shroud in, it was a whole different story. I could go as hard as I wanted in the streets and actually stay cooler compared to some NA setups. I also run a DeWitts without the EOC since I run two externals inline.

My recent change was moving the intercooler out from in front of radiator to help road course duties. It also makes use of an extractor hood.



Arnel

 

You nailed that one perfectly

Most peole don't understand the reason the trans oil coolers are in the radiator and come to that conclusion. The main reason is to "maintain" a constant temperature of the trans fluid regardless of the ambient temps. In the winter, trans fluid can be thicker and cause hard shifts and transmission damage. The main idea of the internal HE was to heat up quckly, maintain, and to cool down. Bowtie Overdrive tells me that when they started using internal coolers their warranty claims virtually went away. For the hard core racers, I suggest running both external and internal, in that order. First the air cools it down, then the water heats it back up a little and brings it back to the tranny at the exact same temperature all the time. This also lowers the coolant temperature a little bit.

 

try different coolant mixtures and water wetter. i run about 10-15 percent coolant with 12 ounces of redline water wetter and it dropped my average temps 20 degrees with stock thermostat and radiator . plus when it does get hot to redline on the gauge and the check gauges light comes on ... i just back off the throttle and cruise at low rpms for about a minute and she cools back down and off i go again!. woohoo! haul *** !!!!!


never boils out of the tank...never. i think your water pump is fried

 

Thanks for all the input guys .
I will try a few things and see how it all goes.
HEY ...AU N EGL , One thing I didn't look for was a dead wallaby that I may have picked up . On second thoughts a wallaby wouldn't fit...hmm..IDEA ....CHECK FOR KOALA in air intake.
Regards to all ,
Peter ..AUSTRALIA

 

guy from ls1tech.com did this:

Originally Posted by PewterZ28 View Post
FINALLY!

We got the Trick Flow heads on and temps dropped a lot. Right before we made the swap the temperature reached 230 with no signs of peaking. Of course we pulled over and left the electric pump running with the fans on and the engine off. After installing the Trick Flows the temps were only reaching 202 on a 20 mile drive on the highway. At idle temps would slowly fall back down into the 190s.

I still wasn't satisfied so I looked over everything one last time. I had already tried taking off my Super Sucker Ram Air while my stock radiator was on but I had not tried taking it off since installing the Be Cool radiator. Well, the Be Cool radiator is a lot thicker and it really closed up the already small gap in between the SSRA and the Be Cool. I know from past experience that blocking the radiator can cause overheating on the highway. So I thought what the hell and took it off just to see.

Now? How about 178* on the highway and holding steady! And my friend was able to meet up with me last night and get my car completely tuned on the street, part throttle and WOT. Tonight is the last night of racing at my local drag strip so I am really looking forward to it after a season long fiasco. I'm on my way to the dyno in a couple hours here so hopefully I put up some good numbers on the dyno and the strip. The car feels really strong.

Many thanks to everyone who helped with their hands or their minds.

I think in summary I had "the recipe" for overheating...clogged radiator, contaminated coolant, blocked coolant passages and finally a partially blocked radiator.