Heat dissipation question

[jinaeve]

I'm looking for advice regarding optimal heat dissipation from the heat building up in my '59 Apache w/496 Stroker. That big engine compartment allows you to stuff a Big Block in there but isn't optimal for efficiently dissipating the heat.

I don't want to install a giant Harwood racing scoop, I just want to get rid of the heat by installing something old-school looking and simple - I'm not a fabrication genius and don't want to spend a ton of money on this.

Appreciate some discussion on this topic... thanks all!!

 

[Lakeroadster]

When is it overheating? Does the problem also exist when the truck is sitting still?

Have you tried removing the hood, just as a test, to see if it helps the overheating issue?

Tell us more about the engine and it's components. Maybe post some photo's.

Headers?

Radiator shroud?

Electric fan(s) or engine driven fan?

Are there panels around the radiator to channel the air through the radiator that prevents air from spilling around the radiator, instead of through it?

 

[jinaeve]

When is it overheating? Does the problem also exist when the truck is sitting still?

It vapor locks when driving at around 40-45 mph and once it vapor locks, it keeps happening several times until I shut it down. I'm saying vapor lock instead of overheat because the engine gets up to around 215 - 225 which is about what I expected from a BBC.​

It does happen while stopped but the engine also gets considerably warmer at idle too.​

Have you tried removing the hood, just as a test, to see if it helps the overheating issue?

Yes, see my other post where I provided an update to this same question.​

Tell us more about the engine and it's components. Maybe post some photo's.

I already did that, also see previous post and see my photos.​

Headers?

Yup, ceramic coated Headman long tubes.​

Radiator shroud?

Yup, highly custom, I'll have to take some more shots to better understand.​

Electric fan(s) or engine driven fan?

Electric.​

Are there panels around the radiator to channel the air through the radiator that prevents air from spilling around the radiator, instead of through it?

There are vented panels around the radiator but more than likely not vented enough. Again, I'll get some more shots of the core/shroud combo in a few days when I get back home.​

 

[Lakeroadster]

Air Extraction Hood

If you have multiple threads about the same topic, maybe you could merge all the data here? Makes it much easier for us to help answer your queries.

Air Extraction Hood

Modern Corvettes, Camaro's and Mustangs have heat extractor hoods that release hot air from the engine compartment to provide extra cooling. Basically they have a recessed area with openings that create a low air pressure area that pulls heat out of the engine bay. On the new Z/28 this also provides considerable down force too.

Maybe adapt one of these hood center section to your classic pickup?

More discussion here courtesy Camaro5: Best Hood/Hood Modification For Heat Extraction



​

Thanks,

John

 

[jinaeve]

I like where you're going - still not sure whether its enough but I finally got around to getting some photos yesterday of my engine compartment to show you what I'm contending with. I met with a buddy of mine and came up with an idea to punch some holes into the firewall where the cowl vent is and let the heat dissipate through the cowl vent - thats a unique approach and haven't yet figured if there are any serious repercussions to doing this or not. I don't drive the truck in the rain or inclement weather, too dangerous, but I do drive it quite a bit.

The following is a link to a conceptual photo of where I'm thinking of punching some holes through the firewall at the cowl - would appreciate some feedback.
https://www.flickr.com/photos/20518846@N00/16363956559/in/set-72157650436843087

We're also talking about fabricating a bit of an air dam just over the front sway bar to catch more air as I'm moving.

Here's a link to my Flickr page and more photos of the engine compartment:
https://www.flickr.com/photos/20518846@N00/sets/72157650436843087/


Thanks again for the feedback!!

 

[Lakeroadster]

Wow.. what a beautiful truck you have... simply stunning.

After looking at your photos a couple things come to mind.

• Cutting holes in the cowl? I'd hold off on that for now.
• The holes in the shroud beside the radiator?. plug those, same thing with the holes in the sheet above the radiator. You want all the air that comes through the grill to go through the radiator.
  
• It appears your radiator shroud is flat on the back of the radiator? How much space is there between the shroud and the radiator fins? Most shrouds are conical shape to allow the air to come through the radiator and then not restrict it as it moves toward the center and out through the opening at the fan.
  
• Often the shroud will also have a couple small openings that have rubber flaps on the back of it (see photos below). This allows air to exit when you are at highway speeds, but they close at slower speeds so the fan can pull the air through the radiator.

 

[jinaeve]

Wow.. what a beautiful truck you have... simply stunning.

Thanks Lakeroadster - its been over 3 years in the making...​

Cutting holes in the cowl? I'd hold off on that for now.

Yeah, not real sure I want to do that either​

The holes in the shroud beside the radiator?. plug those, same thing with the holes in the sheet above the radiator. You want all the air that comes through the grill to go through the radiator.

Not sure where you're going with plugging the holes on the sides but I can do that.​

As for the holes on top of the radiator, there's no air flow there, its just dead space above the radiator there for architectural effect, nothing flowing through there.​

It appears your radiator shroud is flat on the back of the radiator?

Yes, thats correct - was someone else's idea... I trusted their "experience" over my gut - should have gone with the gut ​

How much space is there between the shroud and the radiator fins?

NONE! Its flat against the fins... ​

Most shrouds are conical shape to allow the air to come through the radiator and then not restrict it as it moves toward the center and out through the opening at the fan.

I'm painfully aware! I originally proposed to build a conical shroud that accommodated an electric fan but they were adamant this would do the trick because there was very little room for anything else.​

I have to say that you really raise some very good points, all of which were points I was exploring before I swapped out the motor and the radiator surround was fabricated. I was assured there would be ample flow but obviously thats not the case.

One other contributing factor is that this radiator has an automatic trans cooler thats not being used now. I'm thinking that with the added radiator core taking up space, adding another inch of thickness and not serving any real purpose, its making the radiator that much more inefficient as well.

Additionally, I've been reading up on automotive aerodynamics and the cowl outflow idea isn't actually going to be effective due to the turbulence generated at the intersection of the windshield and hood while driving. Thats why cowl induction is effective, it intakes flow at that intersection (logically) so expecting outflow to occur there is a mistake.

I'm rethinking my whole strategy now:

Yank out the old radiator and get another BeCool thats nearly the same size but doesn't have the trans-cooler built in. This will also be about 1" thinner too, giving me the ability to have a bit more space between pulley and radiator to accommodate a conical shroud and electric fan setup.​

Additionally, considering adding a modest scoop

to help provide cool air to the intake.​

Doing this will hopefully help the vapor lock issues as well.​

Thanks again for the great feedback!!

 

[Lakeroadster]

Holy Schnikeys....

It appears your radiator shroud is flat on the back of the radiator? How much space is there between the shroud and the radiator fins? Most shrouds are conical shape to allow the air to come through the radiator and then not restrict it as it moves toward the center and out through the opening at the fan.

Its flat against the fins.

That's a huge issue. Stagnant non moving air means the only cooling you are getting is the circular portion where the fan is. If you run the numbers I bet you're only using about half the cooling capacity of your radiator in the current configuration.

If you block all holes that allow air to bypass the radiator core and get a shroud that allows air flow across the entire radiator it will likely solve your overheating problems.

Let us know how things turn out, looking forward to your response.

John

 

[jinaeve]

Holy Schnikeys....

LOL!​

John, I'm getting on your page now - I'll have to swap the radiator and get a better shroud to make that work though though. The current radiator is just over 3" thick due to the built-in trans-cooler, BeCool sells a 2" version, same width and height that will give me another inch to play with so I can add a conical shape shroud.

The stock core support has vertical louvers on the sides of the radiator. I can block those off before the ports inside the engine compartment.

Thanks for all your help!!

 

[Lakeroadster]

Sounds like a plan.

 

[jinaeve]

Update

I spent a couple hours on the phone yesterday with BeCool engineers talking about my application and they recommended pretty much what you're saying - but stated the current BeCool radiator doesn't have the capacity required for the HP my motor produces. Basically my solution is to replace the radiator and install a dual-fan shroud system - depending on whether it will fit or not.

I'll be looking at this in depth over the next couple weeks.

This will get your motor running...
Chevy Apache Drag Racing Truck

 

[jinaeve]

Update.

I've finished my radiator upgrade and now have no more over heating issues. Engine temp is averaging around 165 degrees and I'm ecstatic.

I still have trouble with vapor lock though and wondering if a return line from the carb back to the tank would elevate the vapor lock issue. If not, what other solutions would be recommended?

 

[66 Truck Drive]

I have a 496 in my 77 C20. I used a duramax diesel radiator and dual electric fans. In 95 degree weather if I'm just cruising the themp on that engine has seen as high as 215, but if I hit on it a little the temp stays around 180. These are large engines that do run hot so if you see 200 don't worry. As long as the water is flowing it won't boil. Course if I moved to CA and drove the thing on a 110 degree day I may see 230. lol But up here in Oregon we never usually see over 100.

 

[jinaeve]

Yeah, I'm in Texas so 100 degrees is common. I'm pretty happy with the radiator I have so far... I dropped in a BeCool radiator they modified to fit my application. I had to rebuild the core support substantially but its in there now and with the dual fans, so far it works like a champ. I was just in stop and go traffic at 82 degrees and it got up to about 180-185 degrees.

My biggest problem I have now is with vapor lock and I'm convinced I need to reroute my fuel lines because they're just not far enough away from the headers. I'm also thinking I should bolt on a ram-air scoop of some kind to help ventilate the engine compartment. I'm not there yet but feel that engine compartment really needs to breathe better. When I pulled into the garage, the heat just blasted out.

I just used an additive I bought from O'Reilly Auto by Lucas Oil products, their "Ethanol Fuel Conditioner" and that seems to have had an impact on vapor lock (from what I can tell). I heard this from another guy that liked it so I thought I'd give it a try - so far so good!

http://www.oreillyauto.com/site/c/detail/LUC0/10670.oap?ck=Search_10670_-1_3927&keyword=10670