ive vented two hoods. The biggest difference I’ve noticed is the increased steering response I got at high speeds. Venting the hood reduces the air intake temperature also. Should be worth a few horsepower.

 

This is a timely read for me. I have a 75 stock engine and hood, the silly engine even, L48, and when I pulled in my garage today after cruising all over for Memorial Day, I measured the top of my hood. this thread made me curious. the outside top of my hood was 127 degrees. so hot to the touch. I think I'm going to install some vents to see if it takes that problem away. I also am missing my insulated hood pad so maybe I need to insulate the hood to stop that from happening. I notice that when it gets hot it is hard to start with the carb which is due to the hot air being sucked in. I am so interested in your finished findings.

 

Well Mr. Dragon, there was a thread going on here just a week or 2 ago about that inner hood blanket. You may wish to look for it. But in summary, the overwhelming consensus was, leave it off. And as for final findings on this forum. Forget it. there will always be debate. You need to make up your own mind.

 

This post was quite timely for me as well.

I’m replacing my standard hood with a louver modified L88 hood. The same Louvers as @OldCadBum points to in thread #37. However, my intake manifold will be standard LS format. And this induction system is not compatible with the original L88 round filter design. I’ll have to bring ambient air from another source.

I mentioned earlier about my foot wells being extremely hot during summer driving. This statement is an example of the heat load within the engine bay and it is not a justification for the louvers. My firewall shielding and insulation is missing. The root cause of my extreme foot well overheating is on me; operator error. A standard Corvette with proper shielding and insulation per GM design should provide an acceptable thermal barrier.

I really don't want to spend a grand for an L88 hood, and then another 300 bucks for the louvers. But, I’m adding cubes, hp, and engine mass; and therefore, my justification for the louvers. They are to provide an opportunity for hot air to escape where possible, when possible. It’s as simple as that.

Hood insulation:

Many years ago I spent hundreds of hours preparing the Corvette body for paint. It was a continuous operation of stripping, sanding, filling, and priming. I thought the paint process would never end. The final touch was to add hood insulation. Unfortunately, my old insulation was shot and at the time, there was not a supply of it in the reproduction market. I chose to use ½” thick, 3’ X 4’ Armaflex closed cell foam sheet. Google it. You can find this stuff at any plumbing or refrigeration supply house for about 25 bucks. It lays easily on the contour of the inner hood and applies easily with 3M spray adhesive or another good brand. It rejects the heat well and once installed, it actually looks pretty good, but opinions may vary.


Yes, to protect the new hood and paint from extreme heat, the underside of my L88 hood will be insulated.

 

When I put my hood scoop on I added two louvers/vents to let hot air out. They work! When I hold my hand there after driving the car, a lot of hot air is coming out from the rear side of the scoop.


cut the holes



two louvers from amazon or summit, riveted on



from the back side - not pretty but I need to clean up



heat comes out of here

 

Here's what I thought would be a "cool" idea- especially with a low profile LS engine- L88 hood cold air intake with a fan- artist rendition

 

The problem with that is the cold air intake actually sticks down into the engine compartment pretty far. it would be hitting the top of the carb. I have a low profile tri power intake on mine and I have to cut the intake to get the air cleaner to fit. THe air cleaner will be sticking up into the CAI. I myself was thing of putting fans at the gills to force air out. And if you ever turn on your heater during the summer you can get another 20 degree drop usually. Imagine to small heater cores mounted at the gills with pusher fans forcing the air out

 

[QUOTE=4-vettes;1602385123]I've been running this vented hood for years. really don't think it makes it any faster. Definitely has to let some hot air out. But never measured it in any way. Just liked the look and wanted more room for my RPM manifold and 3 inch tall air filter. (Not a drop base).


Hi; just came across this thread. Did you install this hood yourself? Are there vent screens on the inside of the vent openings? I'm thinking of putting this kind of hood on my 1980 but can't much lnfo on installation. Any info would be great! Thanks

 

I have this VERY HOOD i(thinking inner hood screens,as well ),n mind for install this winter!

 

Well, that's a picture of my car. That hood has been on that car for over 20 years. No screens. And truthfully, no need for them.