Car Trouble, please post what you think.

I recently had the motor in my 99 cobra rebuilt due to a rod knock caused by the previous owner. I drove the car really easy about the first week, and then, a little after that i decided I wanted to see what she had, well I turned T/C off and I was gonna do a 180, of course I had no problem, but when I pulled back off the road my car died. It started steaming from the engine, and my heart dropped, I looked at the temp gauge and it was fine, so I looked under the hood and saw that it was the hose running from the radiator through the firewall, it had slipped off a little, and that stopped the steaming, and the k&n cone filter had come loose from the intake, so I tightened it back up. After a while the low coolant light came on, so I put some water in it til I could get some coolant. Later that night a 95 cobra wanted to run em, I beat him once, and then again only not as bad because of the burning up out of the hole, after the race I noticed there was a knock in the motor. It doesnt sound like a rod at all, and the sound seems to me like is coming from the passenger side head almost at the firewall, most people have told me it's probably a lifter. If you have any other opinions, please let me know, and if you think the same, what do you think the repair cost would come around to? Thanks Alot.

Yes, actually it does increase with higher rpms. What kind of mods do you mean?

I took the car to the guy who rebuilt the engine yesterday and after listening to it, he seemed to think it was a rod up until he noticed that the knock just stopped when you let off the gas. He said if it was a rod knock it should it should just steadily descrease in the noise. He now seems to think it's either the timing chain about ready to snap or like I said before, a lifter. The a/m mods include just the Eagle rods. The piston that was replaced was replaced with an OEM, as was the crank.