bzimm

Important information: 1999 trans am, ls1 stroked to 383, Huron speed v3 turbo kit, 4” core intercooler, turbo 400 tranny, Griffin stand up radiator, dual derale 2000cfm puller fans, 160 tstat, fans turn on at 170, new gates water pump, 10% under drive crank pulley, no AC, engine has maybe 100 miles on it, car idles at 1k Rpms

I just finished my build and have been slowly getting some miles on the build, but the car has been having an overheating problem. This afternoon I took it out for a 10 minute drive with an ambient air temp of around 88, it was all backroads so no red lights all driving done around 35-45mph and when I arrived the car had reached 215 degrees, verified with my scan tool. I parked and let it idle for 30 seconds and the temp had risen to 230 in that time. On the drive home same story, got back to my shop with 220 degrees of coolant temp and the time it took to open the garage door and park the car it had risen to 230 degrees just this time with an ambient air temp of about 70-75. Cooling system is filled with gm dex-cool and I made sure to get all the air out of the system, each fan has its own dedicated harness with a 40 amp relay per fan. The bumper has been cut out to allow for more airflow. At this point the only thing I can think is a factory water pump is not supplying enough flow to properly cool the engine, but other than that I am at a complete loss as where to go next.
Any advice on how you guys are keeping your engines cool or what I should try next is greatly appreciated.
Thanks, Brad

gametech

iTrader: (1)

Pull your thermostat, verify that it is opening at the proper temperature, then get back to us. If you do have a real problem, there are several people with similar setups who can probably give advice.

bzimm

The thermostat is brand new so I would image it is and you can feel the radiator get hot right around when it should be opening. However not the first time I would have had new parts fail so I will try and pull it to check this afternoon.

Old Buzzard

10 under on the wp isn't helping.....

ddnspider

iTrader: (26)

Either there is still air in the system or the lower air dam is missing.

G Atsma

Get rid of the underdrive pulley. With all the other mods, it is not doing you any favors.

bzimm

The lower air dam is currently not on the car, but I do have it still. Is that the one that fastens to the crash bar? because the intercooler is in the place of that. I would rather change the water pump to a high flow than switch the pulley, with the turbo being there it adds a lot more work to replace that crank pulley.

ddnspider

iTrader: (26)

I have an underdrive pulley and no issues. You need the black plastic air dam back on the car. If you have to trim the sides for intercooler piping that's fine but guarantee that's why it's overheating assuming everything else is in order.

bzimm

This is what you are talking about when you say the air dam ? I will try and get it reinstalled and see what that does.

ddnspider

iTrader: (26)

Nope that's just a shroud. It'll help but not much. This is the lower air dam:
https://www.rickscamaros.com/1993-20...MaAi1MEALw_wcB

bzimm

Ok good to know. That hasn’t been on the car for years, I’m not even sure if I still have it. I will have to buy a new one. Thanks for the info

Che70velle

iTrader: (6)

Wouldn’t the lower air dam only aid in temps while moving? He’s having problems while sitting, where the fans should keep the car cool, especially since he’s cut the bumper up to help with air intake. Sounds like an air pocket to me honestly. They are hard to get out.

bzimm

The car is also overheating while moving so that would help with that but not the sitting still part. One of my friends that owns a shop is going to let me use his vacuum bleeder sometime this week so we can be sure all the air is out.

Che70velle

iTrader: (6)

Gotcha. I mis-read your first post.

psicko

Which radiator did you get? I've read on here that a couple people had issues with the Griffin radiators because they got the ones with the small tube diameters. They upgraded to a different Griffin radiator with larger tubes and the overheat issues went away.

bzimm

It is the one with the 1”-1/4 tubes, I got the part number off of a write up another member did on here about doing the stand up conversion. I did see they offer a 1.5” tube maybe I need that one.

Kawboom

It may sound silly, and it is, but please make sure the fans aren't wired up backwards.

bzimm

So I got some spare time this evening to work on it and this is what I’ve found so far. I removed the water pump and tstat, both are in perfect working order. I bore scoped the cooling passages into the heads to make sure I did not screw up the head gasket install and they were both done properly. I then did an amp draw test on my fans as I’ve already had to replace one of them due to a faulty motor, I found the one fan was drawing about 38 amps, they are advertised at 23.5 I believe, the other fan was right around 30 amps. Which leads me to believe that both of my fans are not pulling near the cfm’s they’re supposed to. I am going to adapt my factory fans to this radiator to see if that solves my problems. They are wired properly I made sure to check that

G Atsma

When measuring the amp draw, is that the starting load or constant load?

bzimm

That was the constant load after about 30 seconds of running.