454BB over heating!

I have a 1969 Camaro with a 454 BB, can't seem to figure out why it keeps overheating only when driving around. The car starts to get hotter and hotter as you drive around, takes about 20mins of driving for the car to overheat. I can start the car and let it sit in the driveway for over an hour and never goes over 200. If I take the Hood off the car it seems to get enough air to where it don't overheat either while driving.

cooling system fan (2500CFI) with shroud, comes on at 180deg

Griffin Radiator 30"x19"

180 thermostat

water pump is new(Napa stock pump)

using 50/50 with water wetter

Cowl Hood


any suggestions would help,


Thanks  

check timing at full advance  

Check the lower radiator hose for colapsing. When these get alittle soft the water pump can cause them to colapse,(Pintch together) restricting flow. While idling the pump is turning slower, no colapse. Let me know?  

Normsride:
Check the lower radiator hose for colapsing. When these get alittle soft the water pump can cause them to colapse,(Pintch together) restricting flow. While idling the pump is turning slower, no colapse. Let me know?

I have checked this, I am using flex hoses for top and bottom and they are both new. I will check the timing this weekend but the bad thing is I have NO clue what my timing should be on my motor.  

I'm not sure where you live, what mods have been done. But to get the correct timing setting for a stock engine, you could go to Auto Zone or the like they will give it to you at no charge. Note; If your doing allot of summer driving, I recommend dropping the Stat temp to about160/165. I'm not saying this is the problem, but it doesn't help.

If timing does no good. Than do what someone else here said? Check the compression and head gasket pressure. You may have a head gasket blown, but no outside leakage at all. It could be a case of pressure change from idle to excell. opening and closing the leak. Seen it many of times. Can't really explain it but seen it. Been burnt the first time I incountered it. Almost gave up, But I don't quit.

Let me know?  

Normsride:
I'm not sure where you live, what mods have been done. But to get the correct timing setting for a stock engine, you could go to Auto Zone or the like they will give it to you at no charge. Note; If your doing allot of summer driving, I recommend dropping the Stat temp to about160/165. I'm not saying this is the problem, but it doesn't help.

If timing does no good. Than do what someone else here said? Check the compression and head gasket pressure. You may have a head gasket blown, but no outside leakage at all. It could be a case of pressure change from idle to excell. opening and closing the leak. Seen it many of times. Can't really explain it but seen it. Been burnt the first time I incountered it. Almost gave up, But I don't quit.

Let me know?

I am in NC.

well mods on the car is kinda hard to give out since the guy I bought it from got the motor from his cousin and wasn't 100% sure what it had done.

Compression is 12 to 1
150 shot of nitrous that I am not currently running.
holy double pump 750 carb
cast iron crank

The motor runs really strong, I am not even pushing it hard off the line at the track and it is running 7.4 in the 1/8th all motor right now.

If I had a blown head gasket wouldn't my oil be milky? the oil is almost clear from being so clean. The guy told me his cousin had the motor blue printed a few years back.

but I will check the compression and head gasket anything is possible.

I drive the car maybe 3 times a month if that,I have only made 4 passes at the track with the car.  

the head gasket could just be leaking in between the cylinders, i would say total timing,  which means hold the engine at say 3,500rpm and time it,  i would say about 34 degrees, maybe 32,  i wouldnt go over 36, then check it as idle,  might need an adjustable vacuum advance if you are using one  

Listen to what oldsfreak is saying. Yes the leak can be between the cylinders which will not leak into the oil ports. Also when it gets hot see if there is any moister coming from the exhaust? It may be very little, but enough to cause overheating. Then listen to oldsfreak. If everything check out?

Let us know? we'll take the next steps.  

Also the head gasket can be blown near a cooling port so combustion pressure would get pushed in the cooling system plus this would be accompied with air bubbles or if severe enough over filling of the overflow tank.  

I have checked the timing and its 32 and that is where I am going to leave it for now, my timing is also locked out.

I pulled all the plugs out and noticed that the threads on the plugs had some oil on them and not sure if this is normal? I was only able to do a compression test on 1 cylinder and it was 165 I still have to check the others just ran out of time.

will let everyone know what i come up with next.  

Did any plug appear cleaner than the others? If coolant is getting in a cylinder, it has a cleaning effect and decarbonizes everything. Hope you find the problem.  

All 8 plugs had oil on the threads but not the tip of the plug. The plugs all looked the same, with the same amount of oil on all thread.  

I think the "oil on the threads" is that who ever put the plugs in put oil on the threads as lube so they screw in easy and don't sieze in the heads. Does this have aluminum heads? Which make sense.  

DON`T forget the main problem. is the water pump right? i mean make sure you did not geat a reverse rotation pump ( for serp belt system). my self i like the fan to be driven by the water pump, you know as rpm increases it does too. since the fan is electric make sure it is turning the right way.  

I did check the Water pump and electric fan, they are both turning the same way.

my compression is 190-205

the heads are cast iron

running out of options