Ok, here is the deal. I put A/C back in my car a while back and it works great, however my car heats up too much with the A/C on while driving, but not at idle. I have an ITR engine with a Fluidyne half radiator with A FAL fan, and a 10 puller mounted directly on the condenser. The car runs perfectly cool with the A/C off. My thinking is the fan and radiator cant keep up with the added heat from the condenser with the half radiator, another thing is on a factory car both fans cool the radiator along with the condenser, so I am sure that helps a lot having 2 fans on the radiator. I have been looking at the fan and shroud combo from T1 race development, which uses a fan that is a lot better then the FAL. I am more or less looking for onions and ideas.

 

sounds like you need more cooling, either a bigger radiator or the T1 setup, which i am not familiar with.
are you sure the mixture is 50/50, the radiator is full, and there are no air bubbles?

 

here is a dumb question. are you using the stock exhaust manifold, and if so, do you have the stock heat shield in place?

If you are using an aftermarket exhaust manifold, is it ceramic coated or anything like that?

The reason i ask is that your engine is under just that much more load with the AC on, which means higher engine coolant temps, which may cause exhaust temps to go up, and so on. you get kinda a snowball effect.

second, is the AC pump going bad and causing extra load on the engine?

 

You would think the opposite right? it should be overheating while at idle and not while driving. sounds like load, maybe your compressor is seizing.

 

Silly suggestion but make damn sure the fans are wired up properly and blowing air towards the engine, not towards the front bumper. Change the Tstat too, Hondas have weak tstats historically. Shrouds always help.

 

All the A/C components are new along with the compressor and is not locked up or dragging as far as I can tell. My fans are blowing the correct direction and are working properly. The thermostat is new as well. Just about everything under the hood is new. The only thing I can think that may be hurting it a little, is a small section of the Fal fan shroud was trimmed for a previous setup I had. As far as the exhaust it has a ceramic coated header. I even did a compression check, and it has even numbers across the board. As a last resort I am going to purchase the 13" Spal fan and shroud from T1 Race Development, which I am told by them outperforms the FAL fan by a lot. Keep in mind it has been 97 degrees where I live and the car is not boiling over in the overflow. I don't think it is common to run a half size radiator with a b series ITR swap with A/C, so if anyone has a setup similar please chime in. And thanks from the input from all of you.
Here is a pic to give an idea of my radiator and fan set up. On the right side I have a 10" puller fan mounted directly on the condenser.
BTW A/C lines are not touching the header as it looks like it in the pic

 

It is from load, My thinking when driving you are generating more heat then at idle. I think a lot of it has to do with a halfsize radiator not having the surface area that a full size radiator would have.

 

Mixture is 50/50 with a bottle of water wetter, and I bled the cooling system with the front of the car elevated. No bubbles that I see. Do the water pumps on these engines slowly preform less, or do they just quit working?

 

one more random idea:

did you remove your heater core? If you just "cork" the lines instead of running them in a loop like they are supposed to be, the car will overheat no matter what you do.

I really don't think it is from load unless your AC pump is going bad. Hondas are known to be over-cooled. A half size radiator even with the type-r engine should be more than enough except in the most demanding situations.

 

You just need to get a laser or IR temp gun and see what the temp difference from the inlet of the radiator and the outled after driving it around a bit, point the gun at a black surface, even the hose, not the shinny surface. Keep checking for awhile to see if you can tell when the tstat is opening, the fan should cycle with the cycle of the tstat.

Next suggestion is to over cool the radiator by making the fan stay on all the time the engine is running, the engine coolant in the engine will still operate the tstat at the same temp but when the water flows, cooler water will flow into the engine and give you a little more cool time. Next thing is to put in a cooler tstat, I think I would just do this but I personally would want to see temps in my troubleshooting to know how good or not so good the radiator is working. A trimmed shroud should not be your problem.

 

My car does the same thing on a zc vtec in a 91 hatch with full radiator. It only does it in stop light traffic. The car will stay cool on the interstate. The problem is the slim fan, you are gonna have to go with the spal fan. I have a 12 inch on my radiator and a 9 inch pusher fan on the condenser. I am gonna try to squeeze the 12 inch fan from vsracing between my headers and put the spal 12 inch on the opposite side. I honestly don't know what I am gonna do if no company makes a manifold that can allow me to run a full radiator in my ef with a turbo.

 

yeah, stock fan is much thicker and moves much more air. Are you running two fans, or just one?

You probably aren't moving enough air. Make sure you have two fans, and/or use oem fans.

 

Yeah, try the spal fan. I know the slim fan I got from vsracing states that it moves 1600cfm. But, that spal fan is a best compared to mine and I still have heating issues in stop and go traffic.

 

Well a little update. I purchased a 13" Spal fan with a custom shroud from Tony at T1 Race development and put it on today. It has totally fixed my problem. I must say this is an awesome fan combo. It sounds dumb, but I am overjoyed. This thing blows like 3 times as much as the FAL. Thanks for all the input from all of you.

 

You are totally right. The FAL fan is junk compared to a Spal fan.