Can headers help reduce engine temps.

[Asanjuan1]

I'm exhausting (no pun) all attempts to help reduce my early Bronco '70 351W with cooling issues. It has a stock exhaust manifolds that read 330-345 degree with my temp gun. I thought that was extremely high. Thinking some shorty headers would help reduce pressure and heat nearest the block? Any thoughts.

 

[jckkys]

Headers greatly increase under the hood temperatures and the engine is in the middle of these. Getting heat out of the engine compartment would be a step towards cooling the engine. The manifolds have far less surface area than headers that get hotter. Something else is causing the over heating.

 

[reamer]

Louvered vents in the steel inner fender would help?

 

[ugly74]

Headers definitely make it warmer under hood.

I’m currently toying with the idea of adding louvers to the hood to vent some heat, as well as relieve pressure so the fan can draw air through the radiator better

 

[blubuckaroo]

The addition of headers made no difference in the cooling.
But I did a 1" body lift at the same time.
If you don't presently have cooling issues, headers aren't going to make it worse.

 

[56f100bbw]

A friend of mine had a 66 El Camino and had the hood louvered and during the monsoon season it would drowned out the engine wouldnt run

 

[SteveL]

What do you have for a cooling system? A mild 351w shouldn't be to tough to keep cool. I run a standard bc 3-core radiator with a shroud with a 180 stat. Both mine stay at 180 in la traffic. They almost struggle to hit 180.

 

[SteveL]

Water wetter helps if it spikes in traffic. I ran that before the bc radiators.

 

[spap]

I ran water wetter in 2000 s GMC Yukon, don’t know it it was the water wetter but I got water leaks all over in about 4 months, again don’t know if it was the water wetter.
Something else is making over heat need the figure that out first

 

[bbaltered]

He never said what his engine temp was, he said his exhaust manifolds were at 330-345.

 

[SteveL]

I've ran water wetter in a few different vehicles over the years to help in the traffic out here. Never caused leaks. It's not a fix all for cooling problems but does help if you live in so cal or Arizona type conditions.

 

[DirtDonk]

Why do you feel that 345 at an exhaust port is hot? Just prior to that it's probably 1100° or more!

Seems like up to 400 degrees on an exhaust port reading is not out of line, but then I really have not studied the normal running of things like that and put it to memory. Usually just looking for consistency, or any heat at all (low temps mean a dead cylinder), but not for an exact temp.
Seems like it can be as low as 250 and still be in the normal range, as well as 400 at the high end.

What temps have all you others read on a manifold?

And back to your setup Asanjuan, what has been done to your 351? Is it over-bored for a rebuild? If so, by how much? And were the cylinder walls sonic checked for thickness? Overly warm 351 Windsors was a very common problem until people slowed down on boring them more than .030" in the past.

Next, what is your ignition timing? If it's less than 10, then I would try upping the advance a little just to see what it does. If anything...

And what else has been done? What engine coolant temps are you seeing? And under what circumstances?
What thermostat? What coolant mix? What radiator? What fan? Shroud or no?

These and probably plenty more questions. We have not seen or heard what you have yet, to fill us in on the gory details please.
We love pics...

Oh, and welcome to classicbroncos too by the way!

Paul

 

[okie4570]

I had headers, no temp issues but went back to manifolds due to the heat in the cab and floor. Now the soles of my shoes don't melt to the floor lol. No difference in operating temps as of yet either.

 

[Asanjuan1]

Thanks everyone...there's no wrong answer. There's always a balance when it comes to cooling. So here's what I've done, keep in mind it runs at 195 when moving, traffic and idling it'll climb to 220+. Its a 351W from previous owner, so I don't know what's been done to it. Run the following; New 190 & 180 thermostats, bottom hose not collapsing, Champion 3 core aluminum rad, rad flushed many times, burped many times, new Kooler h-flo water pump, anti-freeze, then went 50/50 water wetter, added shroud early in experiments, 5 blade flex to a six blade solid mechanical, timing adjusted, separate tranny cooler from day one, and smaller lower pulley....whew!

Here's my .02, 1) the radiator states it comes with 16 fins/inch, the draw through it just seems so weak at idle. Shining a light on the backside was dim 2)I tried some cheap dual fans, but realize cheap means no CFM's. Going to try two true 800 CFM fans, along with the mechanical. But first I'll run a test with a 16" Volvo fan from the scrap yard I found. Those Volvo fans are SO powerful (nearly twisted out of my hand on a test startup), but they just won't on the pull side of the rad. 3) Combo between new rad, dual electric fan and inner fender vents. 4) Couldn't find a EFI type radiator with dual or triple pass, thinking the liquid needed to stay in the rad a bit longer. Temps exiting the rad were about 195 deg/going in at 220deg, a 25 degree drop...that good or bad.

Losing hope ....an '96 Explorer swap is sounding better.

 

[Asanjuan1]

Oh yes, air dammed the rad on all sides.

 

[gr8scott]

thinking the liquid needed to stay in the rad a bit longer. Temps exiting the rad were about 195 deg/going in at 220deg, a 25 degree drop...that good or bad.

That's a myth...think about it, leaving the coolant in the radiator longer means leaving it in the engine longer.
Your exit temps would be higher. Here's a good article about cooling.

http://www.billavista.com/tech/Articles/Cooling_Bible/index.html

 

[bulletpruf]

Thanks everyone...there's no wrong answer. There's always a balance when it comes to cooling. So here's what I've done, keep in mind it runs at 195 when moving, traffic and idling it'll climb to 220+. Its a 351W from previous owner, so I don't know what's been done to it. Run the following; New 190 & 180 thermostats, bottom hose not collapsing, Champion 3 core aluminum rad, rad flushed many times, burped many times, new Kooler h-flo water pump, anti-freeze, then went 50/50 water wetter, added shroud early in experiments, 5 blade flex to a six blade solid mechanical, timing adjusted, separate tranny cooler from day one, and smaller lower pulley....whew!

Here's my .02, 1) the radiator states it comes with 16 fins/inch, the draw through it just seems so weak at idle. Shining a light on the backside was dim 2)I tried some cheap dual fans, but realize cheap means no CFM's. Going to try two true 800 CFM fans, along with the mechanical. But first I'll run a test with a 16" Volvo fan from the scrap yard I found. Those Volvo fans are SO powerful (nearly twisted out of my hand on a test startup), but they just won't on the pull side of the rad. 3) Combo between new rad, dual electric fan and inner fender vents. 4) Couldn't find a EFI type radiator with dual or triple pass, thinking the liquid needed to stay in the rad a bit longer. Temps exiting the rad were about 195 deg/going in at 220deg, a 25 degree drop...that good or bad.

Losing hope ....an '96 Explorer swap is sounding better.

Have you verified that your gauge is reading correctly?

 

[Asanjuan1]

Yes gauges tested.

 

[vintage bronco]

is ignition timing retarded ? that will heat engine up fast at idle.

 

[Asanjuan1]

Additionally, I've changed radiator caps and also have a hood scoop (open on rear).