454 cooling issues

[prairiehotrodder]

well i took it apart only to find it did have the 1027 head gaskets which is what it is supposed to have. Anyways i went ahead and drilled the extra holes so i can upgrade to the 1037 gaskets for better cooling.

[BillK]

Might need a chin spoiler under the radiator core support, like the mid 80's Camaro, to cause the air to go through the radiator instead of under the car. I think the G body cars had a plastic dam below the radiator and will overheat without it.

You can't road race a mid-80's Camaro without that 4" vertical air dam they have on all production cars. Without that air dam below the radiator it will not cool even at 100+ MPH.

That was exactly the problem I had that I mentioned in my first reply. 85 or so Trans Am. Once we put the spoiler on all was well.

[rebelyell]

Might need a chin spoiler under the radiator core support, like the mid 80's Camaro, to cause the air to go through the radiator instead of under the car. I think the G body cars had a plastic dam below the radiator and will overheat without it.

The little 1-1/2" lip under the radiator on C3 Corvettes is just the right height to get broke off when rolling up to the concrete parking bumper berm at the Dairy Queen and without that little lip they overheat like a pig. In the late 70's we bought so many of those from the local Chev dealer we accused them of being in cahoots with the Dairy Queen to break them off the cars.

You can't road race a mid-80's Camaro without that 4" vertical air dam they have on all production cars. Without that air dam below the radiator it will not cool even at 100+ MPH.

So true about chin spoilers and C3

[Tuner]

Might need a chin spoiler under the radiator core support, like the mid 80's Camaro, to cause the air to go through the radiator instead of under the car. I think the G body cars had a plastic dam below the radiator and will overheat without it.

You can't road race a mid-80's Camaro without that 4" vertical air dam they have on all production cars. Without that air dam below the radiator it will not cool even at 100+ MPH.

That was exactly the problem I had that I mentioned in my first reply. 85 or so Trans Am. Once we put the spoiler on all was well.

Now if he gets rid of the electric water pump and puts a regular fan belt driven pump on it, so it can have the pump pressure in the block upstream of the thermostat, his problem will be solved.

[prairiehotrodder]

Well the new 1037 head gaskets are installed, extra holes drilled in the block, fresh oil change, back up and running. hopefuly find out soon if all that work made any improvement.
Thanks again for all the help.

Brian

[F-BIRD'88]

Might need a chin spoiler under the radiator core support, like the mid 80's Camaro, to cause the air to go through the radiator instead of under the car. I think the G body cars had a plastic dam below the radiator and will overheat without it.

You can't road race a mid-80's Camaro without that 4" vertical air dam they have on all production cars. Without that air dam below the radiator it will not cool even at 100+ MPH.

That was exactly the problem I had that I mentioned in my first reply. 85 or so Trans Am. Once we put the spoiler on all was well.

Now if he gets rid of the electric water pump and puts a regular fan belt driven pump on it, so it can have the pump pressure in the block upstream of the thermostat, his problem will be solved.

Good point. Those electric water pumps are really just for drag racing.

[prairiehotrodder]

I spent the day at the track and the car never got hot. Went 10.93 at 123. Though the real test will be a street drive.
Brian

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[Tom68]

I spent the day at the track and the car never got hot. Went 10.93 at 123. Though the real test will be a street drive.
Brian

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That sheet metal will work when you fill the sides in.

[prairiehotrodder]

Went for another drive yesterday and this car is still wanting to get hot. Going down the highway it will creep up to 200 * and if you work it then it will heat up faster. As soon as i let it sit and just idle the temp comes down fast with the fan on. The fan makes no difference at highway speed. It seems like no air is going through the rad. I've got the air dam as you can see in the pictures now. I'm wondering if the aero dynamics of the car without that front bumper could be the problem ? Seems to me that a front bumper would hinder rather than help airflow ? Also it has been mentioned about the electric water pump. I suppose thats a possibility but its the same pump thats on my 9 second 555 BBC malibu and it runs just fine. At the track the problem not noticeable because i make a pass and let it cool down and it never really has time to get to hot.
I did the head gasket swap to the 1037 new style gaskets and drilled the holes in the block but that didn't help.
Brian

[barnym17]

An old rule of thumb that GENERALLY holds true is overheating at low vehicle speeds is an airflow issue at higher speeds is normally waterflow issue.

[ClassAct]

An old rule of thumb that GENERALLY holds true is overheating at low vehicle speeds is an airflow issue at higher speeds is normally waterflow issue.

^^^^^^^^THIS^^^^^^

If your water pump is under driven make it 1:1 at least. Over driven is better.

[Tom68]

No bumper might mean you have high pressure behind the radiator (depends on inner guards) needs a big fan then to get air to flow if that's the case.

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That sheet metal will work when you fill the sides in.

Went for another drive yesterday and this car is still wanting to get hot. Going down the highway it will creep up to 200 * and if you work it then it will heat up faster. As soon as i let it sit and just idle the temp comes down fast with the fan on. The fan makes no difference at highway speed. It seems like no air is going through the rad. I've got the air dam as you can see in the pictures now. I'm wondering if the aero dynamics of the car without that front bumper could be the problem ? Seems to me that a front bumper would hinder rather than help airflow ? Also it has been mentioned about the electric water pump. I suppose thats a possibility but its the same pump thats on my 9 second 555 BBC malibu and it runs just fine. At the track the problem not noticeable because i make a pass and let it cool down and it never really has time to get to hot.
I did the head gasket swap to the 1037 new style gaskets and drilled the holes in the block but that didn't help.
Brian

You have an engine bay full of high pressure air, as high a pressure as the face of the radiator is seeing, you're in stall.
Of course your fans not wired backwards is it.

The other option is to cut the hood out further forward until you get to the back of the radiator, that should have low pressure there and pull some air through. The existing hood cutout is seeing high pressure from the Windscreen.

[Schurkey]

454 in a 78 malibu street / strip car. Very basic combo that wants to get hot at cruise speeds. Its 9.7 CR with a big aluminum aftermarket radiator, mezier electric water pump, gutted thermostat, and a small electric fan.

Warms up quick even with a gutted thermostat because there isn't enough coolant flow, and stays hot because there isn't enough air flow.

Oh, sure, you need vacuum advance, and to assure the fuel curve isn't overly-lean. Air dams can help, and a PROPER fan shroud.

But the first two things I'd scrap are the electric water pump, and the "small" electric fan.

[BLSTIC]

Do you have a way to measure air pressure across the radiator? If you can it will help develop an undertray and air dam a lot better and faster.

I had one car that was a constant overheating mess, and by sealing the airflow so that most of it had to go through the core rather than down or sideways, and making a quick and dirty undertray sealing the bottom of the bumper to just past the radiator support panel (in this case that was the easiest combination of 'rear most, takes cable ties, doesn't move or glow') I was getting the same pressure drop across the radiator at 50km/h that I used to get at 80. Turned from 'overheating all the time and especially when you hammer it' to 'the temp gauge moves a bit when you stop and cools immediately when you move again'

[HQM383]

.....The fan makes no difference at highway speed. It seems like no air is going through the rad.

As a possibility have you considered the size of the trans cooler? Air will be going through the rad at highway speeds but at a reduced rate and pre warmed with the large trans cooler in front while the engine is making more power (heat) at highway speed than idle. Cross flow rad most coolant will go past that trans cooler. Fan, electric water pump and radiated heat can take care of the low idle engine hp output. And as you said the exposure time just isn't there during 1/4 mile run.