Here's my last new post for the day (maybe). In an effort to get rid
of more heat from the engine compartment (and increase air flow)
I'm experimenting with some hood vents. Beth and Richard donated
a hood:


I took it to B & M Auto Body in Berkeley and had Bob cut some vent slots
and paint it:


It didn't look too bad when he was done


Then Bill and I installed it:


I think it looks good, I'll have to see if it improves air flow through the
engine compartment.


Thanks Beth, Richard, Bob, and Bill, also to Marc T
for suggesting the location.

 

Looks good. Are those just holes, or are they actually louvered?

 

Mark,

These are slots (holes) cut in the hood. I plan to put a screen on the back side and if I have time roll
the front lip up. If it rains, I plan on putting racing tape across the slots. I hope it doesn't rain too
much this summer....

 

Not bad George. I'd be interested in seeing the longer-term effect. Hey, can you check to see if air goes IN or OUT there?

 

Heinrich,

That should still be a low pressure zone. Further back at the base of the windshield there is
a high pressure zone, so I wanted in front of that, but near the fire wall so the air is forced
out. Marc also suggested the point along the front axle should be avoided.

 

George I'd think carefully about the possible updraft over the cats / headers ......

 

Boy I feel like I'm being negative here! But that's not my intent. Just forwarding my best thoughts ...

 

I've given a lot of thought to hot air trapped under the hood - hence the vents on Fat Bully - Your's are much better looking, subtle and fitting for a street legal car.

Nice job.

 

George
It looks like the hood is sitting a bit to high on the corners near the bumper, especially the drivers side front or did you set the hood up a bit higher for better ventilation? Maybe its just the pic too?
I'm just thinking of the airflow at "186" (200+ in reality) would really pull up on that seam!

 

It seems to me that actual louvers would function more efficiently because of their form. The raised portion of the louver causes the airflow to be diverted upward creating a negative area just under and to the rear of each louver, thus sucking out air from under the hood plane. A hole creates no such negative area and may even create turbulence which would seem undesireable.

 

George tapes the seams before the high speed events. Also covers the headlights.

Rich

 

This is the hood on the widebody we are playing with. I cannot say if the cowl or naca ducts do any good, not enough personal experience with the car.

 

Yes, like it.

 

The NACA ducts are aligned with the air intake hoses, good design in theory. This is the car getting the 6.1L +1 atmosphere and a 5-speed conversion. Hey, that's it's new nickname......6.1+1!

 

Dave
The NACA ducts should really improve airflow into the engine plus drop the air temp quite a bit too. Have you tried it at high speeds yet, I wonder how much more lift (if any) the ducts would cause?