Be sure to get the correct thermostat, as the one for the SBC is not the right one.

 

I'll tell you what happened to me. I have a 95 Z28 also. I could drive my car and it would do fine until I had to stop. If I stopped it would start to run hot. So I installed a manual fan switch. Still, as long as I was moving it would stay cool, if I stopped it would run hot. Even with the fans on. I go home. The next day I start the car, after checking the coolant and stuff, and let it idle. Nothing. Car doesn't even attempt to run hot. 15-20 minutes later still normal. Take it down the road come home and stop, needle starts to rise. Waited for the fans, they came on, nothing still getting hot so I turned off the car. Finally I got down to examine the airdam, as if it would matter sitting still with the fans on, I noticed there was a plastic bag trapped between the radiator support and radiator. Apparently, it would hand down when cool, but when driving it would spread out on the radiator and there'd still be enough air to keep the coolant cool, but sitting still at a stop light the bag wouldn't fall down so even with the fans on it couldn't pull enough air through to cool it.

Anyway, pulled the bag out and no issues since. I eventually got the 160* t-stat and reprogrammed my fan on/off temps.

 

No, its not too hot. Appears you didn't fully read my first response.

Running the engine at the 1/4-mark is not all that good. The oil may not get hot enough to drive off the condensation. My engine dyno testing showed I made better power with the engine in the 195*F range. Or, maybe your friend has a 93, with the oddball calibration on the coolant temp gauge, which makes people think its running at about 150*.

 

Thanks Injuneer, Im hopefully going to that guy this week, maybe weekend. I had to get a new computer, as mine is locked down for some reason? Once he programs everything I'll post any noticeable changes, I'm expecting some changes. I'm pretty sure his is a 95, I'll check with him.

 

Well put a new computer in and there was a black wire not even inserted into one of the connectors on the old computer. It's reconnected now, and tuned. I have noticed a change in power now. The shift points are different as are the fans, now the temp hasn't gone over the 1/4 mark during anytime. It definately feels alot better, the guy used C.A.T.S. on a laptop to do it all. Also had to get new O2 sensors, one of them was showing it to be dead practically and the other not quite right, so I had them both replaced. Especially after that the car has run much smoother, a huge difference at idle and all ranges. It appears that was the majority of my problems in the rough ride all along. The only thing left to do is replace the seal behind the harmonic balancer, as the guy said he noticed oil dripping from it. Which I have noticed oil on the ground when it's parked just couldn't really pin point it. I bought the tool to do it with which was about $12 at NAPA, and plan to do the job soon.

 

The black wires are mostly sensor grounds. Seems odd that it wouldn't have set a code for the incomplete circuit.

 

Yeah, but the old computer was locked down also, so it might not have shown up

 

What does "locked down" mean?

 

I had this same issue at idle and the temp shot up. Then cooled when I drove around. I checked my radiator and nothing was there...yikes! I added distilled water to see if I had a leak. Sure enough, I had a leak in my head gasket and needed to replace the entire seal. After that, it was all good! Treat it fast and don't drive on it further until repaired.

 

I mean you could read the codes, but not do anything with it. I had this same issue before at Autozone, I tried to get the codes read but the person there said they couldn't read them. The computer said that it could'nt make a connection to there scanner. At least this guy was able to get a code about the o2 sensors, but when he tried to program it the first time, He said he couldn't do anything with it because it was showing to be locked and unable to program. He said it that it could have been caused by some kind of tampering that maybe someone else had done to it before. I did install a Venom Module a long time ago, though I installed it correctly it could have something to do with it. It could also be the black wire I noted in one of my previous posts too though?