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Pro's and Con's

With apologies for the over use of the word ‘actuallY’ last night. Wasn’t feeling good but wanted to respond.

Paul, are your louvers above the hood line, it's a little hard to tell.

I was considering louvers being under the hood line to attempt to draw air through the stack?

Not certain what is meant by ‘Hood Line’ so, here’s a couple of pictures to save you from my usual 1000 word posts.

2009
IMG_0220.jpeg

2023 before hood flopped.
IMG_7207.jpeg
 
With apologies for the over use of the word ‘actuallY’ last night. Wasn’t feeling good but wanted to respond.



Not certain what is meant by ‘Hood Line’ so, here’s a couple of pictures to save you from my usual 1000 word posts.

2009
View attachment 81910

2023 before hood flopped.
View attachment 81909
And so the louvers are above the hood top surface to grab air and blow it down in around the engine ?
 
And so the louvers are above the hood top surface to grab air and blow it down in around the engine ?
Re re reading RunCool’s web page and reviewing my videos last night, the hood louvers are mostly meant for letting heat out and, it would seem, for people stuck in commuter traffic speeds.

With the string test, it proved that above 35 the low pressure zone towards the windshield is very real as is the ‘messy aero’ flow across the hood’s surface. The known low pressure zone at the windshield is evident too. The air blowing across the Louvers at speed probably isn’t the main cause of the string getting pulled in so much as the air flow in the engine bay going under the truck is. Result, a little more cool air flowing across the back of the motor for an unknown, if any, benefit.

I had thought that some advantage might be taken of that low pressure through a 3” cowl induction for fresh air to get routed to the turbo but, my mind couldn’t get around how it would actually route and be a benefit for the effort. (Edited to stay on topic).
 
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Found the videos. Needs more editing than I can do tonight. On review of the posted video, there was a light blue piece string in the middle of the Right hood vent that had been pulled all the way in by the time we got to 60. In other vids, it was actually being pulled in before we got to 40 mph.
The strings were actually taped under the vents vs. on top like the others on the hood.

About 35mph and already getting pulled inside.

View attachment 81897

View attachment 81896

At High Idle, the fan air was just pushing them out and back.
View attachment 81898

GM Engineers designed air to flow through the stack and the engine bay and then exit out and down under the cab. These vents just bring a little more air into the bay to do...what...help the designed flow? These perform more like cowl induction but to what point really? Aesthetically pleasing as they are, they really only let hot air out while at speeds lower than 35 mph and who's pulling hard enough to need that 'benefit' at 35 mph? Stop and go traffic and post road trip, yes. At speed, IIHO, not so much.

For me, anymore, the point is moot. This hood was destroyed by my negligence (didn't latch, opened at speed, bent. "New" OEM hood in place. Much quieter in the cab too if that helps.
Negligence? I interpreted that to be passive aggressive resolution😎
 
I guess my question would be from what I can tell, Paul's vent louvers (the openings) are facing towards the windshield. I was curious about the openings facing toward the front to "catch" air directing some down into the engine bay. I suppose with them facing ether way in bumper traffic or parked would allow for heat to escape up and out helping a bit with the heat soak scenario.

@Paveltolz where did you source those lovers from?

an idea for thought. it is possible to secure a larger PC fan to the underside of the vent connecting a multi meter to the power leads (no power) which would then tell you which direction the fan begins to turn. I would have to test this myself, but air going in the louvers the fan blades would start to spin one direction and show in the meter a positive (or negative) voltage, if the air is forced out of the louvers you would get the opposite reading on the meter. most PC fans also have a third wire on them to read RPM. not exactly sure on how but I'm sure a meter could be used to somewhat read this as well but we could see if the fan is spinning at full force or just barely spinning too. it wouldn't give us any exact readings for air flow but would give us some idea of the effect on the flow and how forceful it is. weather to vent or not to vent, and how the effect would be if Chris made something to mount a cooler in that area. This idea could also be used in the skid plate area too.
 
“@Paveltolz where did you source those lovers from?”

Would like to hear more about this.
A friend here, old timer body shop man.
Back in the 60s, he took the hood on His 1954 Chevy sedan and louvered that hood.
Seems He had some sort of a device that cut the louvers into the hood and twisted the cuts to make the louvers.
 
“@Paveltolz where did you source those lovers from?”

Would like to hear more about this.
RunCool Hood Louvers. https://hoodlouvers.com/

Mine are the XXL "High Flow" or "Outlaw" units.

My recommendation...buy them unfinished. If you want to go with powder coat, have them powder done by a good third party. The first set I had them do and the material was thin and brittle. The set I have on the shelf now was done 'right' and now I'm just trying to figure out if I really want to do this again.
IMG_7430 (Edited).JPG

IMG_7431 (Edited).JPG
1686757046351.jpeg
If you choose to do this, Kiss a reasonably clean engine bay buh-bye. All the rain, snow melt, dirt, dirt in the rain and snow melt etc. will come right in and rest on your motor. Yeah, it comes through the stack too but, don't say later I didn't inform you.
IMG_7435 (Edited).JPG
 
Thanks for the pics Paul, just what I wanted...

Now I can explain my question better. Your install has the louvers up and leaning towards the windshield, my idea was just opposite that, turn yours upside down, louvers on the underside and pointing forward. I could be way off but in my thinking at road speed it would "pull" air from the engine bay and enhance stack flow? Someone with more knowledge than me might enlighten me..
 

This is more of what I am looking into. Their video in a wind tunnel showed air moving from the engine bay out the vent.

Although these don't look very strong....
 
Thanks for the pics Paul, just what I wanted...

Now I can explain my question better. Your install has the louvers up and leaning towards the windshield, my idea was just opposite that, turn yours upside down, louvers on the underside and pointing forward. I could be way off but in my thinking at road speed it would "pull" air from the engine bay and enhance stack flow? Someone with more knowledge than me might enlighten me..

While unscrewing the motor issue, I had those ‘tacked’ on with just one rivet in each corner. So, for testing purposes, you could do the same.
Here’s the ancient thread I did on their install. Pictures still come up as well as a second video.

One issue with an upside down install is clearing the hood’s cross members. I chose not to cut them out but, they could be trimmed so the louvers will set in. It would be interesting to see what comes of that config.
 
I have a 4" cowl hood so I have lots of room. I'm leaning towards the brand I linked, just not that specific one. They have loads of wind tunnel videos and they do funnel air through the stack and out the vents. I've also seen the vents nascar is using and the same idea is used. So at some point I will go that route, I have the stock hood in case I screw up...
 
Just a thought.
You might try reaching out to Bruce (Raceday mechanic) at PT Wiring Solutions. Haven’t spoken to him since Rusty Wallace Racing was still operating but, he may be able to offer some insight as to what NASCAR has going on. If he’s not still in the game, he’ll probably know people who are.
 
Just a thought.
You might try reaching out to Bruce (Raceday mechanic) at PT Wiring Solutions. Haven’t spoken to him since Rusty Wallace Racing was still operating but, he may be able to offer some insight as to what NASCAR has going on. If he’s not still in the game, he’ll probably know people who are.
You can find him on Facebook if nowhere else
 
Spitballing as always. Chris, are you going to run any bumper chin dam? I think they were to try to push air down and clean airflow around the front diff and A-arms etc (to create neg pressure behind stack). Same with the plastic skid plate?

Nate did something once..... back in this thread: https://thetruckstop.us/forum/threads/my-water-to-air-intercooler-install.44492/page-10

I sorta doubt any of this can fit but wonder if a custom tank to / core-bars angle would straighten the airflow? Or terrace 2 shorter coolers and fab up modified tank tie together? Could any angled flaps on the side of the skid plate catch or deflect some air to clean the airflow at frame and inner cv joint?

Might be smaller with a straighter flow would equal to larger with angled flow?

Just imagining stuff?
Light green line is chin bumper dam add holes or scoop of some kind or increase neg engine bay pressure or encourage nostril flow???? Maybe catfish front bumper holes and scoop downward? Red and yellowlime straight thru level with ground core bars, dark blue angled tanks or terraced tied together? , light blue deflectors air flow dam sorta like the radiator stack "dam" or second chin or dam to encourage negative back pressure. This new lower dam would be like a shroud not necessarily built into cac but sealed as needed to be a flat ish face only air could thru cac not escape around it. Shroud could be foam sealed and made to just hide hoses and stuff????
 

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