Solofast

Well, yes it would be nice if folks did some research before making a fool out of themselves. Just because the AVERAGE pressure under the hood is greater than on top doesn't mean that there is lower pressure at the base of the windshield than there is under the hood.

As Evil Twin noted, further forward on the hood the pressure is lower because the air is moving quickly over the hood. As you approach the rear of the hood the pressure is higher because of the stagnation of air at the base of the windshield.

The overall pressure difference multiplied by the area results in enough force to lift the hood. At that point the air escapes out the sides and the pressure is relieved. This "demonstration" of unlatching the hood has nothing in common with trying to let out air at the base of the windshield. Because of the stagnation area there, little or no air is going to come out of the back of the hood.

As Evil Twin (a retired GM design engineer who knows the subject) noted they looked at this in the wind tunnel and determined that it made no sense to try to vent the hood in this area. It is nice that we have input from people with an engineering background and test experience who understand the subject and are willing to provide the benefit of their experience in these kinds of threads.

SyndicatePlus

I know this is a bit old thread, but on the Engineer section of Drive this guy talks about Heat being the number 1 enemy of just about any type of racing. Heat + Time is an interesting debacle. Gives good info for venting hoods on Corvettes.

I have an extra C5 hood I am going to Vent for sure I also live in Las Vegas, gets mighty hot in summer.

_zebra

^^ good learning points there!
back in august when i raced the car in pueblo, co, i've never seen it get so hot in my life! it was about 100° that day & at 5000', there wasn't hardly any air to cool anything!

as for the hood, i originally wanted to do an extraction vent like the MCM, but for the same reason their hood won't fit a PD blower, the intake snout's in the way of adding a duct (which is why i reckon the camaro blowers have the angled intake port)

SaberD

An easier mod would be to remove the fog light shrouds in the front bumper. You can also do the front license plate cover screen mod. You could also get a lower temp thermostat and get the fans tuned to a lower temp. You could also install one of those cheap $200 aluminum radiators. Also make sure your coolant is clean and new.

_zebra

and where's that extra air go after you open up the front? that's one of the reasons i ain't done it yet.

Crabr1

Here's my KB hood,opened up,no issues what so ever,not any dirtier either.

SyndicatePlus

Yeah, don't put a cheap radiator in your car. If you can afford a Vette, you can afford to put a good radiator in it.

I've already put a low temp thermo & adjusted the fan speed. Helps a bit, but not enough in the Vegas heat. Doing a DeWitts Rad & Spal fans before the summer time.

Smoken1

I lived in Vegas for over 8yrs never had any problems. BTW its not the fan speed that needs adjusted its the temp they turn on at

SyndicatePlus

Well aware, I used HP Tuners to adjust my fans & get rid of CAGS. I never said it was a problem, but 220F is too damn hot in my opinion. I don't see 190F since the adjustment, but that is just daily driving. Planning to go with boost, so vents + Spal + DeWitts will be good insurance.

Did you by chance get to Race out at Spring Mountain ? I've got a few friends in the Corvette League, so I might join up at some point.

Smoken1

Nope never raced out at Spring Mountain. Where I live now in OR. I doubt heat will ever be a prob...

NITRO UK

Hi mate
My stock hood is still hanging on the wall , not for everyone but very tempted to cut a hole in it for TVs blower , more for looks .

Would like to think there's a positive vent wise ??

_zebra

worth a shot... at least your blower would blend in with the paint

TRAKOUT

I thought I need more air flow, the hood was bowing up above the front wheels at speed and temp was hitting 220 . I like drilling holes in stuff and installed these vents. They work great temp is down and the hood stays flat

NITRO UK

Thanks bud reckon I'll give it a go at some point .

TRAKOUT , good work mate .

guys