Vented hood thread

[wstar]

Originally Posted by synolimit

Lets say this happens. The hot air doesn't come out but it never did before either. But if you're pushing ambient temp air down into the engine bay then engine bay temps should drop! Whether the hot airs pulled out, or ambients pushed in, we still are achieve a desired goal of getting a lower temp.

The goal is increasing the airflow through the radiator by giving the hot air coming out of the radiator somewhere to go. With no hood vents you tend to just build up pressure in the engine bay and that restricts radiator flow. If you install hood vents in the most wrong way possible, you'll end up pushing cold air *into* the hood through those vents, which will counterintuitively make the car run hotter because you're making the pressure situation worse (because radiator airflow is vastly more important than just stuffing cold air randomly into the bay). A rearward-facing vent that's too close to the windshield can be bad that way, because there's usually a flow of air that rolls under at the base of the windshield and moves forward along the upper part of the hood. Each car is a little different though, and it's hard to say without careful analysis.

[synolimit]

Originally Posted by wstar

The goal is increasing the airflow through the radiator by giving the hot air coming out of the radiator somewhere to go. With no hood vents you tend to just build up pressure in the engine bay and that restricts radiator flow. If you install hood vents in the most wrong way possible, you'll end up pushing cold air *into* the hood through those vents, which will counterintuitively make the car run hotter because you're making the pressure situation worse (because radiator airflow is vastly more important than just stuffing cold air randomly into the bay). A rearward-facing vent that's too close to the windshield can be bad that way, because there's usually a flow of air that rolls under at the base of the windshield and moves forward along the upper part of the hood. Each car is a little different though, and it's hard to say without careful analysis.

Well I've seen a few gtr vents and custom vents and no reports of horrible coolant temp issues so I think we're all good. I mean has anyone here even got their coolant dots over half way? Only thing I've noticed about our car in respect to you saying about the window and air is our car is pretty sealed up. I've never owned a car (which is about 30) that's had so much rubber sealing all the way around it.

[Chuck33079]

Originally Posted by synolimit

Well I've seen a few gtr vents and custom vents and no reports of horrible coolant temp issues so I think we're all good. I mean has anyone here even got their coolant dots over half way?

Stock or NA cars aren't really in dire need of this, it's more for the FI guys since we've got a big *** intercooler stuffed in front of the radiator. We don't need to hamper airflow any more than we already have. If it's over 100 and I've been beating on the car and then get stuck in traffic with the ac on full blast, I can get the temp gauge to move a couple of dots. The OEM gauge isn't going to be accurate enough to show anything but a drastic difference. We really need someone with a water temp gauge. DIGI's vents look like they're in the area where I'd think you'd get the most hot air being extracted at speed. He's got access to a thermal cam, so that should let us see airflow at idle. Unfortunately we don't have many options to test airflow at speed other than short pieces of string all over the hood. It works, but it's a pain in the ***.

[synolimit]

Originally Posted by Chuck33079

Stock or NA cars aren't really in dire need of this, it's more for the FI guys since we've got a big *** intercooler stuffed in front of the radiator. We don't need to hamper airflow any more than we already have. If it's over 100 and I've been beating on the car and then get stuck in traffic with the ac on full blast, I can get the temp gauge to move a couple of dots. The OEM gauge isn't going to be accurate enough to show anything but a drastic difference. We really need someone with a water temp gauge. DIGI's vents look like they're in the area where I'd think you'd get the most hot air being extracted at speed. He's got access to a thermal cam, so that should let us see airflow at idle. Unfortunately we don't have many options to test airflow at speed other than short pieces of string all over the hood. It works, but it's a pain in the ***.

Can't we live log the coolant temps? Isn't there apps too for iPads and stuff to view everything?