327sleeper88

So i have a cooling issue with my bbc swap, go figure.

I have got a new 4 core radiator, new cap with rad, meziere 55gpm electric pump(the highest flow available), twin 13.5" derale fans with built in shroud(the motors are Bosch units, rated at 265 watts each, 5000 cfm total), 160 amp powermaster alternator, all wiring is 10 or 8 gauge. Doesn't seam to matter if i have the air dam on or off, but the crash bar is removed, along with all the other junk behind the bumper cover. The radiator hoses are new, and i am using dex-cool in a 20/80 mix.

it will overheat if i am cruising anything over 55, and by overheat i mean approaching 190, once it is past 190, i shut it off. luckily, i can keep the water pump and fans on while the motor isn't running, but i will only heat up again in a matter of 5-10 min on the highway.

On the other hand, in stop go city traffic less than 45mph, it will stay between 170 and 180.

I am running a 4000 stall converter, th-400, and 3.00 gears. so even at 75mph, i am doing less then 3000 rpm. i don't even need to go above 2500 rpm in the city just cruising.






That black cover is there, this just isn't an updated pic, and the hood is on.





Suggestions?

FtrSpeedy

190 is not hot, 220-230 worries me, at highway speeds do you shut your fans off?

sofakingdom

iTrader: (1)

That's utterly ridiculous.

Too bad you hacked up the nose of your car; that's not where the cooling air comes in from, anyway.

It comes in from underneath. There's supposed to be a plastic air dam about 4" tall right below the rad, which creates high pressure in front of the rad and low pressure behind it; and I think we all know what happens when you put something between a high-pressure and a low-pressure zone.

To the extent you have a "problem" at all, it's OBVIOUS what it is, from your pics. That's not happening in your car. Your car is missing its air dam.

Put the air dam back on it.

Then you can even un-hack the whole front of the car if you want, and put it back like it belongs.

FtrSpeedy

Well for my curiousity in the 3rd pic where its circled, will it cause issues if that cover is missing? If so i gotta fab a cover.

sofakingdom

iTrader: (1)

Generally, it will decrease the efficiency of the cooling system, by allowing air to bypass (go around) the radiator.

FtrSpeedy

Ok thanks, that explains highway speeds it creeps up 15 degrees.

UnstableAviator

Use the air dam, otherwise you will not be able to keep it cool at all. Also, use distilled water, 80/20 water/antifreeze mix, and "water wetter".

But most importantly install the factory air ducting and air dam first

327sleeper88

I had the air dam on, and the front wasn't hacked up. did some tests with air dam on vs off, no difference really. I gave the air dam to my brother (86 T/A), cus his got torn off somehow.

even before with the air dam on, the fans MUST be on regardless of speed. during all tests with or without air dam, front ducting, and the top cover by the hood latch, fans must be on.

The best thing i did was put aluminum sheet metal to fill the empty space between the lower rad. support and the front of the bumper cover.

If i am doing like 130mph+, then cooling is not a problem, but that is because i am only it the gas for less than 10 seconds.

190 is hot for a performance motor like mine. Just about any crate motor you buy that is a drag race motor(dominator, solid roller, 2618 pistons, ect) will have a max operating temp of 190-200. i just want to be on the safe side.

I know the air dam is the first thing people go to, but i am just saying that in my case, it really doesn't make a difference.

idk if this matters, but if the outside temp is 45 or below i can cruise at any speed for as long as i want and it will never go past 180. even on the highway, i can slow down to 60, accelerate to 100, brake to 60 and repeat. no cooling issues if it is below about 45 degrees.

t-top havoc

iTrader: (3)

Your 3rd pic shows a kinked top rad hose. Is it still kinked??

Watch the bottom rad hose when you raise the RPMs-- is it collapsing? Is it kinked?

Other than not having the air dam, do you have the air-scoop thing-- kinda looks like a big snow shovel-- helps direct air where it should go.

If you have the time // patience, fabricate your own air dam & "Ram Air Cooling"

There is a thread or 2 with pics of fab'd air dams.

327sleeper88

the picture looks bad, but the hoses are fine. Its an electric water pump, so engine rpm doesn't matter. My own ram air is the sheet metal you see in the first picture. all the air coming in from the front is directed toward the radiator.

1leg

190 is not hot for a street car. I would let it run and see if it stabilize at a temp or keep going up. I would also be worried about your trans overheating, a 4000rpm stall converter cruising at 3000rpm will have issues unless you have a lock up converter. You also don't mention a tstat. If your running one or a restrictor remove it, this will help the pump to flow more water. I would also use a vacuum assisted radiator filling tool to ensure you have all the air out of the system. I also recommend a 50/50 distilled water/coolant with a bottle of water wetter.