Hi All,

Really I need your help and experience in this issue:


I just finished my car project TT (TTIX kit).
but I’m facing a very big problem with overheat temps.
It reached 230 on idle and goes down when I drive smoothly to 224.
I changed everything you can think about
(New Water pump, New Thermostat stock and 160, New Dewitts radiator and dual Spal fans 2800cfm, New Coolant and VP Racing Coolant additive)

Turbo units are covered by blankets.
All Turbos pipes are ceramic coated.
LS9 new bare block.
Forged internals.
Engine CR is 9.5:1.
TFS255 LS3 heads.

Finally I returned the OEM radiator and fan and I noticed a different while driving minimum temp is 212 but it goes up to 224 when I stop.

Note: Ambient temp around 104-113

Thanks

 

Could be as simple as air in the system. Remove the coolant tank cap, start the car, and see if the coolant goes down. Add as required.

 

Add putting a vacuum on the tank once you have the cap off. Also make sure to have the heater on high, so any air trapped in the heat core is pulled as well.


Really the problem with the trapped air, is the air weep channel on the T stat was not mounted TDC, and why your trapping air to begin with. So for this reason, if the air weep device does not end up TDC, then I will break out a 1/8" drill bit to drill another weep channel in the flange TDC.

Also, if you are running the dual fan with the oem PWM, double check the power connector at the middle passenger side down the radiator for it to be melted, the PWM connector to make sure it not melted, and even the pwm itself to make sure it not cocked. The single fan pulls about a 20 amp load (which still melts the power connector when the fan is over spooled for lower temp ramp ups), and with dual fans, your now pulling about 45 amps through the PWM's ground control circuit and power counnector isntead.

As for quick check on the fan controller, just start the car,turn on the A/C , and make sure that the radiator fans are running. The A/C needs air pulled through the heat exchanger (its in front of the radiator) and uses the radiator fan to do this.

 

You could also look into a Prospeed fan package it pulls in a lot more air come in a plug and plug kit with its own PWM. Sounds like you issue is more at idle which is where these fans will shine. Look at there website they have some demonstrations.

 

Stock rad? When you compress air you heat it. Where is that air going?

 

Since you was building away did you do rear steam vents. Put the dewitts back in

 

Get with the times, since Dewitt has twin fan units that will bolt directly on to their radiators for under half the price as others turn key kits, and the PWM (SSR) controller is only around $60 dollars to buy yourself to keep the saving down to half the price as well.



As for turbo kits, lets come back to all the heat that the turbo's are pushing, much less the needed octane boost for the boost. I'm guessing that there is an air cooler in play (that is not blocking the air intake into the the radiator), and Meth kit in play for when the car is on boost to prevent detonation. The meth kit will help when the car is on boost to cool down the motor, but need to be running a Dewitt better cooling radiator, with dual fan set up to start, to keep the motor cool when not on boost.

 

I did this actually, but it keeps going up.

 

Thanks, Dano

I'm sure there is no air in the cooling system as my garage told me, but do I need to turn the A/C on to bleed all the air inside?
because I didn't fill the compressor gas after the project.

Regarding the OEM module, I changed the old one with brand new OEM one and I doubt it's cooked only with 2-3 running time and the fans connectors are 100% in v.good condition.
I'll fix the A/C today and check the car again and post the latest update here.

 

A/C not charged, has nothing to do with the over heating. Its just that we turn the a/c on, to make sure that the radiator fan is coming on with it in the first place (that the radiator fan is working to start with, and not a wiring/connector/PWM problem isntead).

Also, what has the fan ramping temp been changed to in the tune?

Stock fan ramping looks like this,
Attachment 48335485
But with the heat your pushing from the turbo's into the intake manifold (even with cooler instead), will have a heat run away with the temp up to 199 at 15% before the fan starts to come on.
Note, at 224, fan is ramped up all the way (90 is max), which tells you that the single fan even ramped on all the way, is still not pulling enough air through the radiator to start with. So either you have a blocked radiator in some fashion (could be the turbo air cooler is mounted too close to the A/C heat exchanger that the fan can not pull fresh air from around the cooler as needed, or the heat off the cooler is causing more heat related problems instead. And once you have the A/C in play, it going to push more heat through the raditor, so the heat problem is going to be worse with the A/C on.

So again with the heat your generating into the intake at boost (why you need a meth kit even with air cooler), need to start the fan ramping up way down in the 192 ramp, and increasing the ramp ups from there as well (once you do confirm that your not blocking air into the raditor to begin with. The glitch, stock PWM and wiring/connectors where never designed for such use, so you first burn up the power connector on the side of the radiator, then once that connector has been removed with the wires solder together instead, end up burning up the connector down at the PWM (or just the PWM instead). Hence this happens pretty quick with just a single fan at 20 amps, and when you go to dual fans at about 45 amps, could be a matter of hours instead.

So when going to dual fans, the only wire you will be using from the OEM is the 5v control wire from the ECM to control the SRR, then correct 60 amp gauge wiring (what the SSR can control) from the engine block fuse terminal (fused at 60 amps), through the grounding point on the frame for the dual fans/SRR's power needs.

 

^^^^ this is very true , the fans cannot be on more than 90% duty cycle . You will also need the heater on the bleed the air out of THAT system . then shut off wait to cool then refill accordingly .
2nd ) if the fan connector is melted ( the one in front of the radiator ) repair clean and solder the wires or make sure the weathertight has a good connection ( clean away burned pieces as well ) .

 

Trust me, if you burnt up the oem upper power connector on the side of the radiator from spooling up the radiator fan early/stronger, and remove the upper connector to hard solder it there, all you are doing is moving the problem down to the OEM PWM connector and PWM that will burn up next.

 

Update

Step 1:
I decide to change those Spal normal fans (from DeWitts) and I don't recommend anyone under any circumstances to waste his money on it.
I talked to Brent in SPAL to buy a brushless fan and he recommended me to communicate with Wizard cooling or DeWitts, I send an email to Scott in Wizard cooling and he suggested to go with Dual 12'' Spal brushless fan (3600fcm) (DIY Kit) and Spal wiring kit (215F stat) I'm running stock stat.

https://wizardcooling.com/12-dual-br...t/#tab-related

Step 2:
Relocate the trans & engine oil coolers to fog lights, and change the coolant from 50/50 premix to 80/20 or distilled water with 2 bottles of Water Weter.

I'll post the results asap.

 

nice. Keep us posted.

 

coolant is not circulating

head gasket might be installed backward blocking water recycling in the engine

 

If it’s like what you said, the temp will reach H within a couple of minutes and never get down.

يعطيك العافية

 

The dual brushless fans will be nice not sure if you can fit two 12-inch fans but you can still fit two 11-inch fans which would still be 30%-40% more than the regular spall fans you got. Also the 215 stock thermostat is not doing you any favors you might want to drop down to a 190 or so. The 215 probably doesn't fully open until like 220 or so. The way you have to look at these is what are they flowing under load (which is simulated by the radiator and coolers in front) like 150pa pressure in the chart there from wizard a dual brushless will flow say 2300 cfm whereas the dual 11 inch brushed fan you have flows 1600 cfm - so over 40% more.

 

I’m thinking to install it like the fans position in Prospeed kit plus those fans can be a (puller and pusher) so one in front and the other behind the radiator especially that I have a good space between the radiator and the block (not a supercharged car).

Regarding the t-stat and wiring kit it’s 190-215 to be exact, so the fans will start gradually from 190F up to 100% at 215F.

 

I've had my share of overheating problems with my C6Z track car over the years. Currently running Twin SPAL 11' fans with aftermarket radiator wired directly into the cockpit. This ensured I would not fry the fan controller terminals...., again. Probably not a good solution for a street car.

Here are some ideas to try, or in other words here is what I would try...

Block the bypass in the water pump between the pressure and suction side. This is the hole under the thermostat. This bypass hole is open with the thermostat is closed to allow the engine to warm quickly. Once the thermostat opens the bypass becomes closed, but this is probably not a perfect seal. I used a Dorman Expansion Plug p/n 555-019 which is a 1.125 inch freeze plug. Just pound it in with a socket. You could do this with your old water pump if you still have it. I would also block the heater hose inlet and outlet ports on the water pump and leave the heater circuit unattached. AND, I would take an old thermostat and cut the center out of it to leave a ring with a gasket. In other words remove the thermostat. And put in distilled water w water wetter.

You do all this and then run the car with your aftermarket radiator and fans. Then you have eliminated the bypass, heater circuit, thermostat and fluid type as potential problems. Use your old water pump for this and then you can always go back with your new one based on what you learn. In the end you may still need to do something different with your radiator/fans or you may need to add a bigger oil cooler.....

I have been running with a blocked bypass, no thermostat, no heater and water with water wetter in my C6Z track car for several years now. It takes a little longer to warm up, but it does warm up. Idling I get to 200F max and on track I can get as high as 220F at full race conditions on a 95F day. Looks like your ambient temps are even higher....

Good luck.

 

Great advice, Thanks, bro.
Do you run brushless fans or the regular brush motor?

I'm going to use dual SPAL fans (12' brushless) which their rate 3600CFM and sure I will change the coolant fluid to distilled water with water wetter.
The temp here is very high (118F @ noon - 107F @ evening)