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SCCAITS 11-25-08 12:05 PM

Hood too flimsy?
 
I hacked up a spare aluminum hood but am not sure if it is too flimsy now. It is very light and floppy. I was going to use the stock hinges as I don't have crew and pin it in 4 spots in the front. Should it be okay?

http://img396.imageshack.us/img396/1...0056hb8.th.jpghttp://img396.imageshack.us/images/thpix.gif
4 red dots indicated pin locations.

http://img396.imageshack.us/img396/8...0058xr6.th.jpghttp://img396.imageshack.us/images/thpix.gif

http://img146.imageshack.us/img146/6...0059yw8.th.jpghttp://img146.imageshack.us/images/thpix.gif

jgrewe 11-25-08 04:12 PM

Our first glass hood would lift right in the middle in the front when pinned at the extreme edges.(not my car, the other one in the shop) It now has an extra pin in the middle at the front edge.

I put my pins about where the corners of the headlight covers would be and its fine with the same design hood.

You should be OK, just make sure it is a little lower than the nose piece at its front edge. Your problem may be at the high pressure area at the base of the windshield pulling the hinges in as the hood flexes up.

So what does that skin weigh????

Chedstar 11-25-08 04:13 PM

I have a friend who did the exact same thing. He has two hood pins on the rear corners, and the front hinges. The problem is if you try and pick it up from one side, it bows so much it binds on the hood pin on the other side, and you can not lift it. So it is a pain in the ass, as you always have to have someone help you lift the hood. Which if you do not have a crew, could put you in the same boat.

SCCAITS 11-25-08 08:50 PM


Originally Posted by jgrewe (Post 8749896)

So what does that skin weigh????

11.2 lbs and I did not remove all the paint. Had 7 layers to my count, although I did spend 1.5 hours with some 80 grit and an orbital sander.

I need to figure out what to do with the headlight skins. I am going to try and see if I can get them bonded to the hood, hopefully the welding shop has something to bring aluminum and steel together.

The hood is floppy as heck, I'm thinking 6 pins now, 4 up front and one by each hinge.

Sooner or later I'll be asking jgrewe for a fiberglass/lexan hatch.

jgrewe 11-25-08 10:01 PM

Skip the welding shop and just find some epoxy if you want to stick the headlight doors to the hood.
-or-
I can make a box that will fit one of our 14-15 lb f-glass hoods w/headlight doors built in when you get your hatch!

designfreak 11-26-08 11:06 AM

I just made aluminum covers that bolt right in and replace the whole headlight assembly. They weigh pretty much nothing, and when installed look stock.

http://i242.photobucket.com/albums/f...DSCF0002-1.jpg

http://i242.photobucket.com/albums/f...DSCF0003-1.jpg

designfreak 11-26-08 11:07 AM

I can get you some closup pics of them on the car once it all comes back together in the next week or so if you like, but their pretty straight foreward.

SCCAITS 11-26-08 03:20 PM

I remember you had done those, had not seen pics, thanks! The welding place is closed today, if they can't attach aluminum to steel I'm just going to have some blanks cut from aluminum sheet and welded to the hood to fill in the corners. A little bondo and it'll look like one solid hood - plus be that much easier to access my air box where the headlight/turn signal/FTP used to be.

jgrewe 11-26-08 05:04 PM

You can't easily weld aluminum to steel. Well, NASA has figured it out but they aren't talking to your local welding shop.


Two part epoxy is your best bet. Check out http://www.fgci.com for some small quantities. I've used this stuff to hold stainless screen inside a 1000hp V8 to keep the valve train in the top half of the engine if it comes apart.

TrentO 11-27-08 04:32 PM

Just rivet some aluminum to the hood where the headlight covers would normally go. Bend the ouside edges over and you have connected headlight covers.
I have the stock covers using the stock brackets chopped off below the mounting bolts and a small section of aluminum rod holding the front up for now. As soon as I get some quality time I'm going to mount the one piece hood I bought from JGrewe. It's a sexy unit.

-Trent

RacerJason 11-28-08 08:24 AM

Is there really a tremendous amount of weight savings once you add 3, 4, 5, or even 6 latches/pins? I'm going to run just a pair or sparcos through an untouched aluminum NA hood and have the pin towers come up through the oem rubber snubbers between at the inside corners of the light covers.

jgrewe 11-28-08 08:50 AM

Probably still over a 15 lb savings.

SCCAITS 12-06-08 03:38 PM

This whole project turned out to be a BAD IDEA.

After spending even more time on the aluminum hood and stripping it to bare metal, I had someone weld in some aluminum blanks to the headlight area. He ruined the hood and warped it bad. It was a horrible welding job and it's all jacked up. I even paid him the $80. Another reminder not to find people on Craigslist nor to believe they have a "welding engineering degree from OSU". That hood is trash now.

I decided I'd just remove the bracing from my stock steel hood and then rivet on the stock headlight skins using some 1" aluminum strap on the underside. After cutting the bracing, I ruined the hood trying to remove it. The adhesive used to bond the bracing to the hood was too strong and it dented the heck out of the hood. Looks like bad hail damage. The bracing on the aluminum hood had just lifted right off.

FWIW, the bracing on the steel hood weighed in right at 20lbs. So, a steel skin would weigh about 32lbs.

Time for a one piece fiberglass hood. jgrewe you got a PM.

Tofuman FC3S 12-06-08 06:31 PM

Hey SCCAITS,

A good dry CF hood for the FC should only weight 2-2,5 KG. This compony over here in the Netherlands makes CF hoods for the latest M5 with stock reinforced mounting that weigh in at 2,2 KG! Maybe have one custom made at a simmilar shop in the US?

Edit: I just saw you already PM'd Jgrewe.

Riz.

SCCAITS 01-20-09 01:55 PM

I just couldn't justify the expense right now for a one piece fiberglass. So, I was determined to find a solution.

I started with an aluminum hood and cut off all the under bracing except for a small area by the hinge points as I am going to use the stock hinges. I also cut off about a 1/4" off the inside edges on the hood where the headlight doors are, this was to remove the rolled lip on the hood and have just flat material.

Next, I took some headlight covers and skinned them leaving only the 90 degree lip. On the 2 edges that connect to the inside edges of the hood, I flattened them with a hammer so there was no lip.

The headlight skins were attached to the hood on each side with (4) 1" x 4" x 1/4aluminum strips each with 2 rivets on each strip. I tried epoxy but it wasn't going well. The rivet heads were ground almost to nothing on the top of the hood.

Using fiberglass cloth and resin, I put one layer on the top side of the hood and 2 layers on the bottom side. Lots of sanding in between and finally some body filler made them flush with the hood.

I now have a one piece hood that weighs in at less than 15 lbs. The stock headlights are about 4.5lbs each before skinning them.

The hood has been at the paint shop and I should pick it up and install with 6 hood pins this week.

This is an inexpensive way to make a one piece hood. It is time consuming, but the cost is minimal. I do not have any previous fiberglass or body work experience either. I did learn more than once that fiberglass dust and skin don't like each other.

http://img176.imageshack.us/img176/3...0066aw5.th.jpg

http://img201.imageshack.us/img201/1...0070cp5.th.jpg

David Dewhurst 01-20-09 05:17 PM

***I want to keep the car compliant with SCCA EP and NASA PT rules.***

Within your door guting thread you suggested you have a desire to be SCCA legal with this 2 nd gen E Production car. I presume the hood is for the same E Production car. What rule are you following that makes you believe the pop-up head light covers being one piece with the hood is legal?

SCCAITS 01-20-09 05:58 PM


Originally Posted by David Dewhurst (Post 8895939)
***I want to keep the car compliant with SCCA EP and NASA PT rules.***

Within your door guting thread you suggested you have a desire to be SCCA legal with this 2 nd gen E Production car. I presume the hood is for the same E Production car. What rule are you following that makes you believe the pop-up head light covers being one piece with the hood is legal?

It is not an EP car now nor has ever run EP. It runs NASA PT and has made a few SCCA ITE appearances, in a past life ITS. It may run EP in the future, if I decide to go back to SCCA and do some more work to it. For now, I am sticking with NASA but want to keep it compliant with Prod rules should I find myself wanting to run SCCA again.

With that being said, in answer to your question... I know my first three arguments are lame and not the way the game is played, but if you want the truth...

1. The fact that AWR sells a one piece hood that many EP cars I highly suspect use - http://www.awrracing.com/pages/body.html - AWR even claims it to be EP/GT legal.

2. The fact that jgrewe on this forum also sells a one piece and uses it for EP (to my knowledge)

3. This is an in your face item, meaning not hidden in a motor or whatever, if it was illegal I don't think the two above would be selling them.

4. So, you made me read the Prod rules again and I feel even more confident it is legal now.
"The hood, hatchback, deck lid and fenders can be replaced by components of an alternate material, provided their appearance remains stock." "Retractable or “pop up” headlight assemblies can be run in their open, partially opened, closed position or removed in their entirety. The openings created by the removal of the assembly must be covered with screens or panels. These covers must be the same or flatter contour as the stock assembly in its closed position, but need not retain any bezels/rims."

Clearly states "appearance remains stock" in regards to the hood, which it does and I believe within the intentions of the rule. Additionally, the rules say I can remove the headlights in their entirety and replace with a "panel". If you want to argue it does not "appear stock" I will draw a black line where the seam used to be if we ever race together.

If I want to debate rules, there is plenty of opportunity on the IT forums but I get plenty of opportunity on the NASA PT forums. I'll just lurk on the prod forums.

From the "Full Cage" thread...


Originally Posted by David Dewhurst (Post 8892982)
If the steering wheel is geting to high upward you could always add a spacer between the steering shaft mounting bracket & the dash mounting surface. Just don't tell people what you did with the spacer because it may be deamed not legal.

I didn't expect this from you David :)

jgrewe 01-20-09 06:17 PM

One piece hood/headlight covers have been in production forever. Check all the Miatas, all RX7's, Porsche 914's, Fiat X1/9's. Each one has had a car go through the RunOffs tech after winning the championship in their class.

David Dewhurst 01-20-09 08:32 PM

I hate to piss on your prade guys. Please point to an exact rule that specs that you what your doing now or what you have done in the past is legal. I could give a crap about what who has done.

***Check all the Miatas, all RX7's, Porsche 914's, Fiat X1/9's. Each one has had a car go through the RunOffs tech after winning the championship in their class.***

Pure crap ^ that people who have not been there may believe.

The fastest 1st gen RX7 in the country & THE ONLY RX7 that won the Runoffs didn't have a one piece hood. Hint, the car comes from Texas. & in the last 10 to 12 years I have never viewed a fast 1st gen RX7 with a one piece hood/headlight cover. Even TR's fast RX7 didn't have a one piece hood/headlight cover deal. You really need to watch using the word ALL RX7's.

In year 2002 at the Runoffs after we qualified 4th or 5th in E Production with a Miata & were told in the tech line after qualifying that if we wanted to keep our qualifying time for that session that we had better take the tape off (keep it off) that went over the fender to hood gap & the hood to front snout gap. Tech logic was/is the car never came one piece......................... Don't matter if it's taped, glued or what ever together it never came that way from the factory.

Everything is legal untill a protest is brought against a car.

wrankin 01-21-09 09:16 AM

David,

I think that SCCAITS provided you with the two sections from the GCR which are pertinent for this case. I went back and verified them in the GCR, and there does not seem to be any ambiguity.

9.1.5.9.a.2 specifies that you can replace the hood with alternate materials.

9.1.5.9.a.10.A (which he cites above) clearly states that pop up headlight assemblies can be removed entirely and the opening must be replaced by a panel that matches the body contours. It does not specify or place any restriction on the the attachment method.

Of all the rules in the GCR, this seems to actually be one of the more clearer ones. Of course a quick email to Topeka would not be a bad idea.

There are several ambiguities in here for certain, but I think that these rules are fairly clear.

So am I missing something?

jgrewe 01-21-09 05:43 PM

David, On a 1st gen RX7 it wouldn't make sense so you're right, not all RX7's. I was think only about the FC the thread is about.

And your last sentence says it all.


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