Better Footbox vent solution?

Akimbeau · #1 (**permalink**) 09-07-2014, 11:07 PM

So I was considering a fresh air vent for my footbox area and saw a nice system by Cobra Earl with 2 3" marine blowers in-line and I got to wondering...using only the blowers, would it be a better solution just to SUCK the hot air out of the foot boxes? Just dump it out to the fender well? I know you wouldn't have the advantage of the forced air coming from the front brake vents but you would also not need a cable controlled shut-off...just a switch to turn off the blowers and a dumping point not subjected to inward drafts. Also you wouldn't need the ducting to the front AND you wouldn't be pushing the hot air from the footboxes onto the passengers. This is all assuming the blowers were sufficient enough to do the job of course.

Jump on in and give me your experience with your fresh air systems. Is it uncomfortable to have the warm air pushed past you from the footboxes? Do you think the blowers alone set to suck the air out would be enough? How much would you miss the forced air from the brake vents? Has anyone tried this? A couple of marine blowers a toggle switch and a few feet of 3" tubing might set me back $50...the economics work...will the idea?

Kim

RICK LAKE · #2 (**permalink**) 09-08-2014, 03:17 AM

Akimbeau KIm I run 3 blowers in my car. I steal the air from the front air duct tubes and split it off. I run 2, 4" blowers to the louvers in the fenders to help remove hot air from the motor compartment. The 3rd one is spliced in the right side pipe and sents air down the trans tunnel to help cool the rear diff and inboard brakes. You could run 2 small bildge fans to the foot boxes to move the hot air. Have you looked into tape insolator? It's what HVAC tech use on piping and ducts. It has silver reflector on 1 side and glues on the other side. Works great for heat control My whole trans tunnel has this done encase of a fire. Gives you a little extra time to get out of the car. Mine has a 5 point roll cage. Side notes, no more than 2 4" fans on a curcuit, used 30amp relays and heavy wire in the 12 gauge range. Over build this. 20 amp slow blow fuses. Dropped the under the hood by 25 degrees. Sure it will do about the same for the foot wells. Boating supply shops or E-Bay give the best price. Ps I also cover the blowers with silver tape. The bodies are plastic.

Rick L.

Akimbeau · #3 (**permalink**) 09-08-2014, 12:31 PM

Rick, That's a lot of blowers! Must sound like a jet going down the highway!

I bet it does cool things down. I am familiar with the foil tape, nice idea to cover the blowers. I found the blowers I want to use, just wondering if it would be good to suck the hot air out of the footbox rather than blow it out the passenger compartment.

Anybody else?

Kim

cycleguy55 · #4 (**permalink**) 09-08-2014, 01:36 PM

Put a few more fans in there, add side skirts and you'd have a reincarnation of the Chaparral 2J (Chaparral Cars - Wikipedia, the free encyclopedia).

RICK LAKE · #5 (**permalink**) 09-09-2014, 03:55 AM

Akimbeau Kim under you are on fire. I have had this once, no damage to car with oil leaking on headers at race. Blowers fans blew smoke out louvers in fenders. Nothing came into compartment. I like the idea of fresh air coming from the front of the car instead of hot turbulent from outside. Rick L.

With the motor running you don't heard these fans running. They are quiet. People do jump when they walk by the car and get a little hot air blown on them. I say it's a new bug killer for cobras.

lal Naja · #6 (**permalink**) 09-11-2014, 08:04 PM

I do have 3" bilge blowers sucking sir out of the footwells. I have the blowers wired via a three speed control and I love the option on a long drive when I can set on low. Passenger has her own control.

My blower system is hooked into two independent heaters and allows you to blow warm air into the footwell too, and yes I have used it. Reversing the blower via a DPDT switch sends the hot air to the de-froster vents on the dash when needed as a defroster. I have not used the defrost mode as I've never had the hardtop on the car.

Mine are a little noisy on high as these move a lot of air. I will try to dampen the sound with appropriate materials and cover with foil tape.

Akimbeau · #7 (**permalink**) 09-12-2014, 04:03 PM

I like the idea of a 3 speed switch or a variable resistor. Did you build your own or find one off the shelf?

Kim

lal Naja · #8 (**permalink**) 09-12-2014, 05:14 PM

Quote:

Originally Posted by Akimbeau

I like the idea of a 3 speed switch or a variable resistor. Did you build your own or find one off the shelf?

Kim

The link below will take you to the switch. And if you look at my Cobra Build photos on Facebook via this forum you can see the actual installation on the console panel. I used two switches so driver and passenger have independent control.

Rat Rod Hot Rod Flathead Illuminated Lighted 12V Heater Switch 4 Speeds | eBay

Akimbeau · #9 (**permalink**) 09-13-2014, 05:37 PM

Thanks! I found it for a few bucks cheaper thru auto zone. I got two like you, one for each side...mostly because I think they are only rated for 3 amps...2 on one circuit would be too much. Thanks for the lead!

Anyone else wanna chime in? Suck or blow? Fresh air from the front or thru the cockpit? With a blower in-line how much increase in air flow do you get from the front brake vents?

Kim

lal Naja · #10 (**permalink**) 09-15-2014, 05:00 PM

Quote:

Originally Posted by Akimbeau

Thanks! I found it for a few bucks cheaper thru auto zone. I got two like you, one for each side...mostly because I think they are only rated for 3 amps...2 on one circuit would be too much. Thanks for the lead!

Anyone else wanna chime in? Suck or blow? Fresh air from the front or thru the cockpit? With a blower in-line how much increase in air flow do you get from the front brake vents?

Kim

Wire it with a DPDT switch so it can do both, suck of blow. The fan is a little less effective when run in reverse, but it does work well enough.

TexasSnake · #11 (**permalink**) 09-15-2014, 06:06 PM

Kim,

I have a B&B car with ventilation blowers. They are set up to pick up the incoming air off of the front of the car using the brake duct intakes. I have a inline blower fan with individual off on switches for driver and passenger sides. I also have a fan indicator light for each side. They work great when the weather gets really hot.

TexasSnake · #12 (**permalink**) 09-15-2014, 06:11 PM

Kim,

I have a B&B car with ventilation blowers. They are set up to pick up the incoming air off of the front of the car using the brake duct intakes. I have a inline blower fan with individual off on switches for driver and passenger sides. I also have a fan indicator light for each side. They work great when the weather gets really hot.