440 heating only on highway speeds

[RJRENTON]

Tech question: How did the NASCAR wing cars get their engine and brake cooling and combustion air at 200 MPH? I see pix of the engine compartment with no inner fender liners and "hickies" on top of the front fender.

Depending on a particular model, and NASCAR's rules, some manufacturers took their air requirements from the base of the windshield/cowl area as this was a high pressure zone when at speed. Brakes were cooled by negative air flow around the caliper area due to ducted ground effects....but I'm not real sure.....as best I can recall. Rules are constantly changing and I'm not a NASCAR designer......my best guess.....
BOB RENTON

 

[66 Sat]

I'm not a NASCAR designer....
BOB RENTON

But if you were Bob I bet you'd have shown 'em a few things.

 

[Cranky]

Depending on a particular model, and NASCAR's rules, some manufacturers took their air requirements from the base of the windshield/cowl area as this was a high pressure zone when at speed. Brakes were cooled by negative air flow around the caliper area due to ducted ground effects....but I'm not real sure.....as best I can recall. Rules are constantly changing and I'm not a NASCAR designer......my best guess.....
BOB RENTON

Actually, the cowl area is a low pressure area.....real low at speed.

 

[Jeff Peterson]

Actually, the cowl area is a low pressure area.....real low at speed.

I’m gonna have to go with Bob on this one

“One method that has a racing pedigree is true cowl induction. No, not the rearward facing hoodscoops made famous on '60s GM muscle cars, though those operate on the same principle. We're talking about true cowl induction that sucks air through a cowl vent much like NASCAR still employs today. The idea is to take advantage of the high-pressure zone that naturally builds at the base of the windshield”

 

[Cranky]

I’m gonna have to go with Bob on this one

“One method that has a racing pedigree is true cowl induction. No, not the rearward facing hoodscoops made famous on '60s GM muscle cars, though those operate on the same principle. We're talking about true cowl induction that sucks air through a cowl vent much like NASCAR still employs today. The idea is to take advantage of the high-pressure zone that naturally builds at the base of the windshield”

Think about it......why do your floor vents bring in so much air at 60mph? That is if your car has floor vents.....

 

[Jeff Peterson]

In the CFD pressure plot above note these standard pressure areas common to most cars: very high pressure (red) bubble on the nose of the car, the slight low pressure (aqua) over the hood, the moderate pressure (yellow) bump at the hood/windshield junction and the very low pressure (dark blue) area above the roof of the car where most of the lift is generated. ​

 

[Cranky]

View attachment 1869117

In the CFD pressure plot above note these standard pressure areas common to most cars: very high pressure (red) bubble on the nose of the car, the slight low pressure (aqua) over the hood, the moderate pressure (yellow) bump at the hood/windshield junction and the very low pressure (dark blue) area above the roof of the car where most of the lift is generated. ​

That doesn't show the low pressure at the base of the windshield at the base of it.....

 

[Jeff Peterson]

Your right, shows high or “moderate” pressure.

 

[Geoff 2]

My understanding: the air slows at the windscreen base because the air has to make the turn upwards. Low velocity causes the high pressure at windscreen base.