I finally got around to putting some hood vents on my rig. This project has been bouncing around in my head for a long time. I knew it would take a lot to make this happen. I got fixated on these Sprinter hood vent and could find anything I liked as much.
These vents are not ideal to retrofit to a different vehicle. As a matter of fact, (some of you may know this) these are not hood vents at all. They are the Sprinter's air intake for the vent, heater and AC. Another down side to these is that only the drivers side vent is actually a vent. The passenger side is completely blocked and is only for looks. I talked to several Sprinter owners and none of them had realized this until I pointed it out to them. So to make this happen I was going to have to cut out over 200 little triangles!
The third downside is that in the Sprinter hood they are recessed almost 1/2" so I would have to find a way to bury them that much into my hood.
The good thing about these vents is (I think) they look really good and they are cheap. Genuine Mercedes Benz Sprinter parts, $15 for the drivers side, $22 for the passenger side. Seriously!
But first I was going to have to make sure that I could get these vents to mount into a Ford fiberglass hood. I picked up a old hood from a pick-a-parts for $40, just to figure out if this could be done. After a few evenings in the garage I knew it could be.
So the next thing was to do a full install on a practice hood. The first hood was cut up quite a bit for extra material to make the mounting platforms that would assist in creating the depth I needed. That what this is.
A friend hooked me up with a free second hood that I installed both vents and cut as much reinforcement away as I was comfortable with to let as much air flow as possible.
I then put this hood on my van for a few weeks to see how it would hold up and if I noticed any difference in temps (I'll talk a little more about that late).
After making a few small adjustments I was ready to move forward and cut into my hood. I thought about this long and hard but couldn't convince myself not to go through with it.
I put at least 80 hours into this (about 20 went into cutting out all those little triangles). I'm thinking I am the only one crazy enough to go through with this. So I will have a very unique setup.
There was talk on a different thread about hot air come out of the hood vents and getting pulled into the cab vents. So one of the first things I did was to tape several pieces of string to my hood while on a road trip. This would give my some idea of the direction and pressure of the air. What I found was that the strings were being pulled forward, particularly around the center of the hood. Closer to the sides they were being pulled a bit more to the sides but still forward. All of the strings were only being gently pulled not violently blown, even at 70 mph they were just wafting around as if I was at a dead stop on a windy day. Not at all what I expected. This indicated to me that there is a low pressure zone right were these vents were to be placed. And that any hot air would be pulled away from the cab intake vents.
So did it help? Well even at idle there is a lot of air blowing out of the vents. When the fan clutch kicks in, it is blasting out of them. The most noticeable thing is how quickly the ECT drops when the fan clutch engages. Zeta mentioned this in a different thread and he was spot on. I have gotten up into the 220s but even going up a hill, once the fan kicks in the temps drop. The vents definitely help.
Big project and happy to have it done and no longer just bouncing around in my head.