finshed hood vent's

[jeeper821]

just got done with my hood vent's, and i'am running the rock-it intake tube that i have coverd halfway around, just wanted to know if anyone think's i'll have any neg-drawback's from this?
also i was thinkin of useing a ford rubber dis-cap cover to try to keep the cap dry, so just wanted to know if anyone has done this to keep water out of the filter and the cap. (just wanted to thank my kid for that sticker
thank's for any input.

 

[Mike L]

Looks good, I was also wondering about the sheet metal over the filter as I planned to do the same when i get my vents installed.

-Mike

 

[jeeper821]

it rained like hell today and.......so far it seem's to work, but i still don't have anything over the dist-cap

 

[Ralph]

I'm in the middle of doing mine now. I'm still using the stock air box, so no worries there. I'm also using 70'something 280Z vents. These vents are smaller allowing me to install them away from electrical stuff. The passenger side vent is also partially blocked over the distributor area. I've got the driver's side finished and I'll do the other side tomorrow. I'm taking pics. I'll post them when the job is done.

 

[Dr. Dyno]

The vents should be mounted as close to the front of the hood as possible where there's a negative pressure above the hood if they're going to vent any air at all. If they're mounted at the back, air will be coming from the outside in, not the other way round. There's positive air pressure above the hood in that area when you're driving and that's why the heater vents are fitted in front of the windshield.
The problem with the black metal canister around the Rock-It filter is that it absorbs a lot of heat and preheats the air going into the TB, which is already hot because it's coming from the engine compartment. I'd paint the canister shiny silver so that it reflects the heat and duct some cool air to it.

 

[Ralph]

The vents should be mounted as close to the front of the hood as possible where there's a negative pressure above the hood if they're going to vent any air at all. If they're mounted at the back, air will be coming from the outside in, not the other way round. There's positive air pressure above the hood in that area when you're driving and that's why the heater vents are fitted in front of the windshield.

I don't have cooling issues at highway speeds. The hood vents are for slow, stop and go traffic or summertime wheeling.

 

[casm]

I don't have cooling issues at highway speeds. The hood vents are for slow, stop and go traffic or summertime wheeling.

Out of curiosity, how effective have they been at those speeds? I have a set of the LeBaron vents, but haven't fitted them yet due to concerns over what happens at highway speeds - I'm guessing that the positive pressure just forces air down through the engine bay out along the firewall and beneath the underbody.

Are there any negative effects on cabin ventilation (i.e., does the under-windscreen vent become less effective)? Has it affected stability at speed at all? I usually cruise the freeways at around 75mph, and wouldn't want to create a lift effect under the XJ. My concern is that if it does, I may be better off getting a set of V8 WJ hood vents and trading a little low-speed cooling for stability at speed.

 

[HEX-J]

The only problem with trying to mount them as close to the front as possible is that you'd have to cut into the hood supports. I just cut mine out and the furthest forward I could put them was exactly 5 inches from the rear and I just barely missed the supports.

 

[Ralph]

Finished. Here are the pics. Sorry, not for the bandwidth challenged. I forgot to reset the resolution on the camera.

 

[jeeper821]

look's great, i kinda wanted to use them vent's too, but the LaBaron one's were easy to cut the hole's for, anyway good job, and a very clean look.

 

[HEX-J]

Looks very nice, I like the way you made the mounts out of the old sheet metal, Doooh!!! Why didn't I think of that!

 

[Big Red]

Looks very nice, I like the way you made the mounts out of the old sheet metal, Doooh!!! Why didn't I think of that!

Yeah, I wish I would have done that instead of the RTV sealant alone. But mine aren't going anywhere either. I have the Lebaron vents and love those suckers. :guitar: They look like they were made for the xj. It would have been cool if Chrysler offered them in the xj as well as the Lebaron/New Yorker.

 

[forgiven]

The vents should be mounted as close to the front of the hood as possible where there's a negative pressure above the hood if they're going to vent any air at all. If they're mounted at the back, air will be coming from the outside in, not the other way round. There's positive air pressure above the hood in that area when you're driving and that's why the heater vents are fitted in front of the windshield.
The problem with the black metal canister around the Rock-It filter is that it absorbs a lot of heat and preheats the air going into the TB, which is already hot because it's coming from the engine compartment. I'd paint the canister shiny silver so that it reflects the heat and duct some cool air to it.

So what you're saying is that in darkness, (under a closed hood) a black canister will be hotter that a "shiney silver" canister. "Shiney silver" could still have a matt finish, then what, or what if it's gloss black?