I have an 85 camaro with a sbc 350 bored 40 over and also has a large cam in it and it overheats. I have tried everything I know to try. I have a 3 core aluminum radiator,Dual Electronic fans, recently put on a radiator shroud, I have the high flow thermostat, and I have also tried to use the royal purple Ice to help.. Air dam is still on the vehicle. The block and radiator have both been flushed. Hoses do not suck shut. We know for a fact that it is not the head gasket. I am at a loss right now and have tried all of these things and have had no sort of help with the overheating. Someone please help me figure out what is going on. Thanks in advance.

 

Fill us in a bit more on when it overheats. Scenario and symptoms...
All the time? Idle? Moving? How fast? A/C?

I noticed you never said anything about verifying your water pump is working &/or serpentine is routed correctly IE not flowing backwards through the system (if you have a serpent belt)

 

old school 350. just v belt. new water pump. it will overheat if it idles driving and everything in between. have a 160 tstat once it reaches that temp it will just keep climbing slowly till i shut it off at 210 at idle. and on the hyway it will get to 210 in a matter of minuets and i have no a/c

 

Are you certain that the pump is pumping coolant in the right direction?

I'm pretty sure that a pump that is correct for the serpentine belt will be INcorrect for a V-belt conversion.

See http://www.flowkoolerwaterpumps.com/..._rotation.html
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yes i have the right water pump for it. gets really good flow just doesnt seem to cool it down any. once it starts getting warm it just keeps going up and up until i shut it off at 210

 

Assuming correct water pump turning the proper direction, and properly-operating:

1. radiator
2. thermostat
3. fan
4. temp guage

...what else can it be other than a blocked coolant passage?

Are you SURE the coolant is actually circulating through the radiator?
With the motor completely COLD, fire it up, and hold your hand on the lower radiator hose until your temp gauge reaches the level where the thermostat should open. You should feel the lower hose suddenly get too hot to touch.

Is it hard to crank when hot?
Too-tight crank bearings?

 

it a little hard to start but everyone has told me its because of running the stock starter. they say i should be running a mini starter

 

and when i started it the top hose got burning hot way before the bottom one started getting hot. is that normal?

 

That's abnormal.

The top hose should not be "burning hot" unless the thermostat is open. If the thermostat is open the bottom hot should be fairly hot too (keeping in mind that the coolant cools somewhat as it passes down through the radiator).

This is sounding like a cooling system "vapor lock" (trapped air in the cooling system).

There are varying ideas on how to bleed air from the cooling system.
See: https://www.google.com/#sclient=psy-...cooling+system

 

I have changed fluid like 5 times and different rad and nothing is helping it out at all. so i don't think its a air bubble

 

I hate to jump in here but im having the EXACT same problem and dam near same components, how cld ya tell if the crank/rod bearings are too tight?

Zacks i feel your frustration. Sorry to jump in without help. Oh what pulleys are you running zacks? I scrapped my underdrive pulleys.

 

just pulleys off an old motor

 

Take thermostat out and see what happens with no thermostat at all. Even new ones can be faulty.

While its out test it in a pot of water on stove with thermometer in water see what temp it opens up.

 

If it still overheats with no thermostat then you have a blocked passage somewhere. Most times this happens in the radiator. I had a newer radiator and fought it for months trying to figure out why it overheats like yours is doing. I went out on a limb and took radiator out and took it to a radiator shop to see if it was plugged. Sure enough they called me and said it was plugged so tight they could not fix it. went to napa, bought new one. Poof. ran great.

 

Still to this day i can not figure how it got plugged. I bought it new. Put about 5000 miles on it. Engine locked up. sat in a clean garage for about 4 years. put it back in when i got new engine. 2000 miles later it kept overheating like yours. ?

 

with no thermastat it still overheats. not as fast but stil does. the rad is less then a year old and had the same problem with the one before it also

 

I'm still suspicious of the water pump in the context of the serpentine-belt system removed.

Start with a COLD engine, and the radiator cap off.

When the thermostat opens, confirm that the coolant GUSHES into the radiator.
If you leave the radiator cap off while the thermostat opens fully, it should make a big splashing mess.
If the coolant just sort of oozes through the top hose, and into the radiator, you have a water pump issue.

 

If you have a stock type single row aluminum, I have found they are marginal even in a stock type engine. My 350 (stock except for cam upgrade) ran hot with a songle row. An upgrade to a 2 row Champion aluminum rad solved my problem.

 

my motor was never a serpentine system. and it flows really good. as of the rad its a 3 core champion all aluminum

 

Its time to rule in/out the integrity of your head gasket.

The NAPA combustion gas test kit gets good reviews.

I hope you don't have a failed head gasket. But, the usual suspects seem to have been eliminated.

If it turns out to be the head gasket, be sure to get a professional to evaluate the mating surfaces of your heads and your block. If the mating surfaces of the heads and the block are not true, you will never get any head gasket to seal.

 

i have had the block and heads looked at before and have put 3 head gaskets on. but i will a compression test to see

 

Have you checked the timing?

 

Who looked at the block and heads, and what tests were performed?

Unless there is a severe head gasket leak, you might not discern anything definite by compression testing. If one cylinder is down by 10%, how do you know the head gasket is the issue.

You need to test for combustion gas in your coolant. The NAPA test kit will accomplish this.

The fact that three head-gasket replacements did not solve the issue does not mean that there are not flaws in the planar surfaces of the block or (more likely) the heads.

 

Well i figured out my problem. my fans were not powerful enough. i put a flex fan on and put my fans infront of the rad. now the hottest i see it is 195

 

You mentioned it overheats at any engine condition IE idle, highway, traffic, etc...
You said your air dam is hooked up and functioning properly.
You said you have a 3 core alum. radiator.
Weather today in Winfield KS shows 92 high, 74 low.
You said your fans were not powerful enough.

At freeway speeds with a functioning air dam and 3 core alum. radiator at 92*, I cant see any reason for the fans to even come on, little lone overheat.
Something doesn't add up...