OK this is kicking my ***, here is what I am working with. I have a 1999 Trans Am LS1 4L60E P1SC at 15LB Boost max. I have an LS6 Intake, 85mm Throttle body, large intercooler, Griffin 400-600HP Radiator (17X19X3), 16” shrouded 2400CFM fan, new 160* thermostat, 60lb injectors, NKG TR6, Stock internals, Moser 12bolt 3.42 gears, Sub-Frame, sway-bar and tower strut brace. Tuned by me with HP Tuners Pro and a NGK Wideband.

The issue is I am over heating at 2000RPM’s. Idle at a light and I will cool down. I have tried switching my fan from a pusher to a puller with no change. I have tried “riching” up my tune from 14.5 to 14 to 13.5. I have changed my fan setting to account of the 160 thermo, and tried not cutting the fan off till 270* to see if that helped. It didn’t…. My only line of thought now is that since my radiator has less surface space and is wider it’s not cooling down as well and its pushing through the thicker radiator quicker…..
Anyone done this before or had any similar issues? Would the fix be a larger fan or scrap the radiator and go a different wrought with a wider unit? I have been messing with this for so long that I need a fresh look. Thanks for the help.

 

Well sounds like you already tried this. It she. I had over heating issues it was the same thig wouldn't overheat idling but driving around it would. I figured out that my fans were spinning the wrong way. Switched the wiring and boom problem fixed.

 

Is your airdam still in place under the front bumper to deflect the air into the rad?

 

Fans are correct I did have to triple check that, and the airdam is removed but the license cover is removed to allow air to flow as well as the ram air hood. Today I am going to let it idle at 2K taking heat readings until the fan kicks on. Anyone else had any issues like this?

 

You have to put the lower airdam back on. I saw this same thing happen back when I was NA and just messing around with painting my airdam. I drove around without it and the temps instantly shot up. I suspect that without it, the air going under the car actually creates a low pressure spot and won't allow the air to get to the radiator.

I bet if you put the airdam back on, you'll solve your problems instantly.

 

That will be in my trouble shooting today. Thanks for the pointer I will let you know.

 

any word on if putting air dam back on helped your overheating issue.

 

I have it back on just haven't had a chance to drive anywhere yet. I got a Taurus 3.8L fan too just incase.

 

OK For closure, it was airflow. I removed my intercooler and allowed air to move through the bumper and it stayed cool. I had to run to GA for a few but will be back before summer is over. I may have to go a different wrought on an intercooler.