BlackWorksInc

Okay so after working out the kinks with the mock-up last night I decided to go ahead and tack weld the blades in and get the hood ready for the Bondo Phase of the project.

It was all going well...

Until I realized that I hadn't flipped the template and one side was facing the wrong direction just like my mock-up.

Ended up using the Plasma Cutter to nick the welds and then ground them down with an Angle Grinder; I will have to fabricate some new blades and instal them when I have the time.

So this the vent that I ended up putting in backwards:



This is the correctly placed vent:



And this is the hood at the end of the day when I headed home:


I'm not sure when the next update will be because I am planning on going up to Tahoe to snowboard this upcoming weekend, so I will probably try and finish it before February ends... or the beginning of March... Sorry bout that mates... :Sweatdrop

BlackWorksInc

Well, back from working in Sweeden at a family friend's mechanic's shop, the guy was a race engineer on the pit crew for the Romanian Ferrari Racing Team.

Anyways, I figured you guys were owed a little bit of an update on this project.

Well Franken-hood will be used in the recovery of my RX7 later this month, I am just waiting on Billy to fill my order with some of his wonderful RE-Speed Poly Bushings.

The damned thing has been sitting against my house colecting surface rust like no other; that's going to be a bitch to clean off. Well I still need to weld in the second set of vents since I fucked up doing it the first time. (See above posts if you don't know what I am talking about)

After that I will use a little filer to clean it up and then primer it, hopefully it will work as I designed it to and look stylish too!

So keep I will keep you posted on the progress!

-Paul

warwickben

iTrader: (1)

want to make me a set.

DivinDriver

iTrader: (15)

Makes me wonder if anyone's ever tried a full "aircraft polish" finish on an RX...

warwickben

iTrader: (1)

when you say "aircraft polish" do you mean like raw metal?

rotary#10

iTrader: (38)

sweet fab!! keep it up!

DivinDriver

iTrader: (15)

Yep, except with steel, of course, you'd need to clearcoat it.

Example of "full aircraft polish":

http://www.flickr.com/photos/9816199...7602204355652/

warwickben

iTrader: (1)

i thought that what you ment. figured you where going to post a link to the dmc 12.

TheRX7Project

iTrader: (3)

Friend of mine has a De-Lo. Polishes up nice with industrial SS cleaner.

DivinDriver

iTrader: (15)

Only deLoreans I ever saw were brushed stainless finish - - I always thought a mirror-polish would look amazing.

When I was just out of high school, my gf and I dressed up and went to the local deLorean dealer, to see if we could bullshit our way into a test-drive.

Didn't get to drive it, but the bored salesman (not a lot of deLorean action in Omaha in 1981) did take us for a test drive that firmly convinced me that I was a sports-car guy at heart.

Her father had restored a wrecked deTomaso Pantera while we were both in high school, but neither of us ever got so much as a ride in it before he sold it.

TheRX7Project

iTrader: (3)

The Deloreans also came in red, white and black (yes, painted- from the factory). My friend actually put a deposit down on a red one- and the guy wrecked it the next day moving it around! He had some bad luck getting his De-Lo but he loves it.

I think unless you did an old-school flat black hood, you'd get blinded driving a mirror-polished car.

And back on topic, the hood looks great!

elwood

iTrader: (1)

Man, will you hurry up and finish this thing : ). I want to see how yours turns out before I try mine. I want to do the same basic thing you're doing, but I'm thinking of wider louvers in the center section of the hood, like the Tesla's. I'm trying to move as much air as possible to cool my turbo motor.

BlackWorksInc

That's a relatively easy hood to make really. If you have ever sen the tesla with it's hood open you see that its really a CF box frame with the panels attached on top.

Those louvers run the entire width of the hood, so really the hood is more or less shingled.

As for finishing this project, I need to get the 13B in the shell first... and I have no crossmember so its a pita

Hyper4mance2k

iTrader: (40)

Looks great, but you might've just done the exact oppisite of what your goal was here. You might want to read this 3 part series before you finish up your project. The biggest problem I've found with our car is how long the hood is it's hard to actually put a functioning vent on it. You might be putting the vent in a high pressure zone and forceing more air into your engine bay there fore raising the engine bay air pressure and greatly reducing the efficiancy of your radiator and oil coolers. I've tried to explain this in past carbon fiber vent hood threads but people allways argue and ignore the physics because it looks like a vent so it will vent air. Your best remidy if in fact those are in high pressure area's, which I'm 95% sure they are from my testing, is for you to put a lip in front of your vent that will direct air up and over the vent creating a low pressure area. Then air will actually flow out of the vent instead of in. But there are draw backs the lip will cause drag and slow the car. If that matters to you.
http://autospeed.com/cms/A_2159/article.html

elwood

iTrader: (1)

What kind of testing have you done? Most pressure maps I've seen show the high pressure zone at the base of the windshield transitioning to low pressure about a foot away. The attached image is a general pressure diagram (not a real pressure map), but it illustrates the basics. In general, the arrows indicate the direction the air will flow. DemonSpawn's vents are in what is usually a low pressure zone.

All this stuff concerns static pressure, so it dictates what will happen if the vent is facing normal to the direction of air flow. If you aim the vent forward or aft, dynamic pressure comes into play, which can overcome some static factors. An example is the forward facing roof scoop on many racecars. This scoop takes in air to cool the driver and/or other powertrain stuff. Although it's in an unquestionably low pressure zone (static), it does ingest lots of air due to the dynamic pressure.

Enough science. Smoke is the best way to tell for sure. Bolt that baby on the car, pour some oil on the header, drive it around, and let's find out. If smoke comes out of the vents, they work!

BlackWorksInc

Yeah... I will finish the hood and clean it up as much as i can... as for testing it.. I need to build my rx7 first... and judging by the complications I am running into that may be an issue...

But I will update as i get closer to a finished product.

These vents may not be the most optimal of places to put them, but in theory, the air flow through the front scoop through the radiator should be enough as normally it is forced under the car, given an option to go up and out along with good enough ai current over the vents should cause the venting effect I am looking for.

Hyper4mance2k

iTrader: (40)

If you read all 3 parts to the article I posted it shows you how to test with a manometer or a magnehelic. I did the manometer and saw high pressure all the way down the hood except for in front of the radiator.
Here's another great read. They both have enough info for all of us to learn something and do our own testing for less than $10
http://autospeed.com/A_108656/cms/article.html 1 of 5 part series
http://autospeed.com/cms/A_108674/article.html 2 of 5
http://autospeed.com/A_108675/cms/article.html 3 of 5
http://autospeed.com/cms/A_108676/article.html 4 of 5
http://autospeed.com/cms/A_108677/article.html 5 of 5

http://autospeed.com/cms/A_2159/article.html part 1 of 3 series
http://autospeed.com/cms/A_2160/article.html part 2 of 3
http://autospeed.com/cms/A_2162/article.html part 3 of 3

elwood

iTrader: (1)

My man, kudos for doing some real testing, but I think you got your readings reversed. The curved hood of a car is like the top of an airplane wing. Without explaining all the Bernouli stuff, it's a low pressure zone. There's nothing unique enough about an RX-7 to make this different from every other car on the road. The front of the radiator is most definitely a high pressure zone.

Your readings may be very accurate, but I'm afraid you have the values inverted.

Hyper4mance2k

iTrader: (40)

I ment on top the hood in front of the radiator. I'm only refering to air flow over the hood of the car right now.

Hyper4mance2k

iTrader: (40)

I don't know if I said it yet, but that hood does look amazing. I really hope that it does work out casue if it does I might have to rip off your idea. But if it is in a high pressure zone all you'd have to do is add a littl .25" lip in front of the vent and the drag around it will create a little low pressure zone and cause air to escape from the engine bay and make those very functional. If you look at this Evo's hood you can see little lip that create drag and low pressure to make the hole in the hood actually finctional.

sorry if I'm thread jacking.

thunkrd

iTrader: (1)

is that the mariah mode four? and those side mirrors look kinna ugly. but the wheels are nice

Hyper4mance2k

iTrader: (40)

not my car. anniversary racing front. watanabe rims, and stock JDM mirrors...

SooperRex7

I might have the wrong end of the stick here, But is he not putting the vents on the hood to let air out (not in), from a highpressure area( under the hood, which i got from the autospeed link you posted) out into the normal atmosphere which would be normal pressure.?
so therefore his vent should work alright?
correct me if im wrong because i would like to install vents soon.

RotorMotorDriver

iTrader: (1)

The vents are in fact to let air out. What Adrian is saying, is that if the pressure over the vents on top of the hood is greater than the under hood pressure they will not work that well, if at all, due to the fact that the higher pressure air will look for the "path of least resistance" and flow back under the hood preventing any venting. He is also saying that during his testing, he has found the areas those vents are being installed in is in fact a high pressure area. Make sense a little?

My question to the topic is, does the venturi effect play a role in this, or is it over-ruled by the pressure zone differences? Meaning, the air passing over the vents could possibly cause a venturi effect, but the high pressure just pushes it down into them instead?

Simple venting I can see how you could have a problem with pressure differences, but Im curious about the venturi effect over the vents... It seems that faster moving air over the lower pressure area with slower moving air would create such an effect, which would effectively draw the air out from under the hood.

~T.J.

BlackWorksInc

RotorMotorDriver-

I was actually thinking of the same thing when I designed these vents, I had thought about the pressure differences (I didn't have a chance to measure, just study theory) and was curious about a possible venturi effect. Logically I would think that because of the way that the air is rushing over the hood it should cause a venturi effect in some way. (perhaps only at higher speeds?)

I haven't tested this and its just a guess, when I finish the hood later this Semester and the RX7 I will take her on the 580 and run her hard to see how well the vents work.

In the mean time stay tuned for me finishing this project up, it still has a lot of cosmetic stuff that needs to be done once I install the fins in PROPERLY this time!