SN95 Issues with Cervini's Ram Air Hoods in the rain?

[Chythar]

I'm moving soon and plan on installing a Cervini's Ram Air Hood I've had in storage for a while. I don't have the ram air hood kit so the duct holes are simply open to the engine bay. Will I have any worries driving in the rain? Or parked in the rain? It may not rain here in Southern California often, but it does. I just want to make sure I won't be causing myself issues in the future.

If there are issues, any thoughts on blocking off the vents? Plastic wrap and duct tape doesn't sound like a good idea, but might be okay for the few times it rains here.

As usual, I'm probably overthinking the issue as the intake vents aren't big and the vents at the back will probably suck any water right out of the engine bay.

 

[Mustang5L5]

I would block off the vents. 2 reasons

1. blowing rain and crap down on the engine
2. forcing air into the engine bay at speed disrupts the pressure balance inside the engine bay. You are trying to get air to flow through the radiator but if you create another path for air to easily blow down into the bay it might create high pressure which hinders air flowing through the radiator.

That's why cowl hoods are a popular design. They take advantage of a low pressure region at the base of the windshield to create an exit for air entering the engine bay which helps "suck" the air out.

Hood vents are different....

 

[Chythar]

Well, I blocked the vents off on the Cervini's hood and installed it. I was hoping to repaint the hood before installing it, but oh well. The paint is a mess, but it kinda matches the rest of the car. Here's the underside of the hood, where you can see the two hood vents and the holes I drilled for the block-off plates I made. I used self-tapping screws and carefully tapped the holes. Used cardboard to get the right shape for the block-off plate, and I had an aluminum bar that was just the right thickness. Second photo is a closeup of one of the vents.

I painted the block-off plates red, then used red RTV to seal around the edges. Hopefully they won't leak! Here's a front-facing shot of the Cobra with the new hood. The only clearcoat left on the hood is over the driver's headlight. Oh well.

The hood bolted right up, but there wasn't any adjustment at the hinges so the hood is really close to the driver's fender with a big gap on the passenger side. Not sure how to fix that. Clearance at the front of the hood is pretty equal, but the passenger front corner is up higher than the driver's corner and I couldn't adjust it down with the bumpers. Does that mean the hood is twisted? Probably.

I had to clearance the striker on the hood so the latch would fit. The striker was a bit too narrow, so it would "fit" when I closed the hood but the latch wouldn't come out of the hood afterwards. I had to reach behind the bumper to unbolt the latch to open the hood again. A bit of grinding on the striker behind the latch (not where the latch hooks on to) and I was able to pull the hood free of the latch. However, I couldn't get the secondary latch to catch. After unbolting the latch, I could get it to catch on the hood - then lowered the hood to find that the latch was about a half-inch above it's mounting location. I ended keeping the pins on the latch and just drilled new holes in the bracket behind it. But the hood fully latches now, and the hood release works correctly. I pulled up on the hood as hard as I could, and the secondary latch wouldn't come loose. So I hope the hood will be safe at speed.