hood raising

[andrew7]

My engine temps climb in stop in go traffic, even with the side louvers. This weekends showcars on parade had me concerned about N.C. in july sitting in a slow moving line at the ralley.(heaven forbid but it could happen) I wanted to get the hood punched but their expensive and for the cost I can buy the tool with dies. So I decided to try a different approach, raise the rear of the hood. I took aluminum flat stock on three standoffs bolted to the lip with a slight bend to match the hood contour. It doesn't ruin the body lines and when the fan kicked on, hot air was blowing out. I'm taking a long ride tomorrow to test it out.

The pics are not great. I think it looks better in person from any angle but you get the idea.

http://www.usa7s.com/aspnetforum/upload/1574976886_7pics 014.jpg

http://www.usa7s.com/aspnetforum/upload/584513707_7pics 015.jpg

[slngsht]

great idea. How are you dealing with the latches?

[andrew7]

My latches when I first put them on were rivited to high, making them too loose. I compensated by putting a slight bend in the latching bar to tighten them up. Today I bent them straight like I bought them and that gave me the extra clearance. See Mazda you always have to plan a head.. Many guys latches are spring adjustable also. My main concern on tomorrows ride is negative pressure by the windshield will not allow hot air to escape. I'm not sure.

[andrew7]

I went for a ride yesterday, 145 miles of mostly 2 lane roads. The car is the best yet, between getting the air pressure set for the tires and shocks plus increased caster and top cover. It made for a very comfortable drive. Dad noticed my rpms and speed are the same. 3000rpm is 30mph and 7000rpm is 70mph, guess what, the tach tops out at 15000rpm. The engine was running 165-185 degrees with the air temps in the high 80s.

At a stoplight it will climb 20 degrees in 30 sec, even with "WaterWetr" and an aluminum rad. I ran into traffic near the end because of school which was running stop'n go to 5 mph, from there the temps shot up. The hood helped and the cockpit was getting smothering hot from the side vents rolling the heat up and in on us. I finally pulled off in the shade, shut the engine down for 15 sec with the fan running then started it up for 10 sec to circulate cooler fluid into the engine. During the first time the gage hit 245 and the light came on then dropped below 230. I went back out on the road and played run and coast with the car. Once it cleared to 20-30mph the temps went back to 200 degrees. I need to get more airflow over the radiator with another fan or better duct work. The trouble with the rad is its curved. Bottom line is you can feel the heat coming out the top of the hood, so it worked.

[locost7018]

I assume you have blankoffs around the rad to keep air from getting around it, right? Russ

[andrew7]

yes Russ, I do. I left about a 2" space above the rad for cooler air to get to the air filter otherwise the engine would be only sucking hot radiator air. The bike originally came with 2 small fans behind the rad on each side. They were bad and expensive to replace so I went with one larger fan but because the bike's radiator is curved I place it in front. I think I can get it closer and rivit some rubber flaps around to force the air through. I'll make that change soon, maybe the next couple of days. I just know in traffic I have to keep a eye on it.

[locost7018]

Is there any way to get fresh air to the carb with out going over the rad? Scoop? I put one on mine because the air cleaner sticks thru the bonnet. Air will take the path of least resitance. I did not think having a little air going around my rad would matter till I blocked it all off. Now I never have any overheating problems. Any air going around will screw things up. Put a temporary blockoff in and see if it changes, Russ

[andrew7]

Russ, did you see the picture of the hood above? Its too pretty to go under the shears. Plus it makes the car look more vintage and hides the F1 engine inside. I understand what your saying but any movement will bring temps down. Even a 20mph steady drive will keep the temps down. What I found out when the fan is on, the air is coming out the sides and not through the radiator. I need better shrouding between the fan and rad.