does the upper and lower radiator hoses get hot? could be the water pump. the radiator could be blocked. it's not completely out of the question because you said it started when you installed it. i would remove the thermostat (easiest to fix) and drive without it and see if it over heats. if it doesn't then get a new thermostat. if it does, then you know the problem is somewhere else and i would bet it has something to do with the new radiator.

I'm gonna pull the Tstat tomorrow and try that out ..Thanx.

Gutted an old T stat put it in and wired a switch to turn on the fan.
On a 34 degree evening I thought I would give it a whirl.
Same result.In town perfect temps. Hell really low temps and then when I run it a few miles hard on an open stretch of road...BAM!!!! I notice coolant on the windshield and sure enough the temp rises. Anyone have anything for me? Any trouble shooting ideas? It seems like the higher rpms and the higher speeds are effecting it. After I let it sit with the fan running (the whole time) it kools right down, I put water in it, and fire it up and drive easy home and there are no problems :angry:

Has anyone had any problems with air pockets in there cooling system?

got to auto zone get a coolant tester make sure you heve enough coolant mixed in with your water.
Did you add more coolant after you changed you radiator?

initially I put in a mix of antifreeze and water but since this I've only been adding water to it....Shouldnt be that sensative??????

I had the same problem.... believe it or not, it's your radiator cap! $8 for a new one. The spring may be shot or the seal broken. I couldn't believe it either. Try it and let me know.

already tried it....didn't work

ok, well since coolant is getting on your windshield. then you have a leak. check to see if the hoses are connected tight at the bottom and top of the radiator. are the hoses popping off or what? are the fans actually coming on? if you think you might have a air pocket i would add more coolant then take the radiator cap off and let the car run. also, while you have it running look to see if the coolant is flowing. if it isn't then your water pump is dead.

I had the same problem of coolant coming out of the overflow bottle. I'm going to do a leak down test because I think its the head gasket. You might want to do the same, because it sounds like we are in the same boat except mine did run long enought to overheat.

The reason the coolant got on the windshield is cause I put one of those summit reservoirs on it and it has a little hole on the top instead of a oveflow tube that redirects the fluid under the car.The fan is on a switch and was running the whole time. When I fill it up initially I fill it all the way. Grab the lower radiator hose and give it a squeze to suck coolant through. Then put more coolant in and then fire up the car until it gets to a warm temp and put the cap on after topping it off....Not trying to be a dick but the water pump is a turbine that is run off of a belt.If it's not leaking and the water pump is not making noise and as long as the timing belt is turning the water pump is pumping. I do wish I could somehow measure flow.After it gets hot and I let it cool and replace the fluid I've noticed that the lower part of the radiator is really cool but the top is still very warm ...Anything???If I'm cruising along at a normal cruising speed and the radiator and water pump are doing there job then how would speeding up for a bit affect the system??? I'm thinking it's loosing the fluid and then getting hot.like some kinda problem with the coolant getting past the cap?????? Anyone got any other ideas?

add more coolant

when i changed my turbo i lost a little coolant and just added water, i had coolant coming out of my resiviour (boiling)

Sounds like you head gasket I would reccommend a compression test and see how the numbers come out. Also you said you keep refilling fluid well where is that fluid going? Check your oil for coolant. If your compression comes out good and there is no coolant in your oil or vice versa I wouldn't worry about it but you should probably check those two.

Did a pressure test on the cooling system if there was a head gasket issue it would have shown it. There are no leaks in the cooling system.

I'll change it to mix when I fill it back up.I'm gonna try a different pressure cap...

I don't think a pressure test on the cooling system will show a leak in the head gasket but I could be wrong. If I was you I would do a compression test to be absolutely sure, but its your car.

Pressurising the cooling system would push the coolant through any leaks like the head gasket.....But I talked to Mike at RRE and he suggested the head gasket also..So I will do the compression test.
He said that the gasket might be misaligned and with higher rpms = boost might be leaking and pushing through the colling system. I'm game...I'm getting real tired of this problem...Anyone else own a friggin money pit???? Crankwalk + Buschur Screwing me + center dif+ melting a piston + locking up an oil pump which made the T belt fail + all of this on top of all kinds of other crap......I'm ready to put a bullet in something....

Did it overheat before you put the radiator in?

Yeah i have the same money pit. 3 days after getting my car the flywheel bolts rethreaded out of the crank, not cheap. After less than 2 months blew the head gasket

Didnt over heat before the radiator. I pulled it last night and I'm having it checked out today. Thanx

Yup I have a money pit too. Just put over 2g's in mods on it and now the head gasket is gone. When I get it all back together an tuned I bet the stock clutch goes next. I expect these things to happen though because the stock parts weren't meant to handle the stress being put on them now. So hopefully once I get the bugs worked out it will be fine. You might not even have the oil and coolant mixing because it depends where the crack in the head gasket is. So do a compression or leak down test and find out whats wrong. Did the coolant ever go on the ground so you could look at it? If so did it have bubbles in it? If so then odds are its your head gasket.

I really think the radiator is blocked. If the the top of the radiator is still hot and the bottom is cold, than there is something blocking the radiator. I especially think this because it happened after you got the new radiator.

Yeah i agree with norb, if the compression is fine i would definitely try a different rad.

Never heard of that kinda radiator, but make sure to have that checked out first as said before

Radiator flows 3 or more gallons more then stock so the radiator is cool. I went ahead and bought a water pump and I'm gonna tackle that this weekend. Anyone have any helpfull hints on this install?