CF Hood Attachment

[Bodhi]

I received the SoS CF Type-R hood today. After looking the hood over I am impressed with the overall quality but am concerned about the attachment hardware compatability. I have doubts about the thread holding capacity for the primary and secondary hood latches. I have done a considerable amount of fiberglass repairs on boats and am dubious of self tapping threads in any FRP, even CF with vinylester resins when constant vibration is introduced. If I was doing this from scratch, I think through bolting would be the prudent approach.

Anyone have any experiance with mounting details or retrofit advise?

 

[Bodhi]

BTW, its a 1991.

 

[Jeff@Carbon6]

You could always use a good panel adhesive like 3m 8115 to increase the holding power. It really depends on air pressure under the hood as to how much force will actually be pushing up.

 

[Q]

I have this exact hood, and I've been sweating whether or not the hood latch attachment is strong enough. I've been debating ever since I got it whether or not to install hood pins. I don't exactly want hood pins to spoil the look, but I also don't want the hood to blow over at speed.

I'm also concerned with under hood pressure, and that's why I'm doing a front undertray and duct.

 

[evof575gtc]

is your concern that the threaded holes are just drilled into the fiber glass?

the holes arent threaded fiberglass.
it's sandwiched in with metal threaded holes.
VIS sucks, but they're not that stupid.

I received the SoS CF Type-R hood today. After looking the hood over I am impressed with the overall quality but am concerned about the attachment hardware compatability. I have doubts about the thread holding capacity for the primary and secondary hood latches. I have done a considerable amount of fiberglass repairs on boats and am dubious of self tapping threads in any FRP, even CF with vinylester resins when constant vibration is introduced. If I was doing this from scratch, I think through bolting would be the prudent approach.

Anyone have any experiance with mounting details or retrofit advise?

 

[VBNSX]

you'll be fine...

I have the same hood and track my car regularly.... I even have the sos radiator duct which pushes air through the hole...

I have gotten to speeds around 150 on the track and have had no issues so far...

slap it on, drive and have a good time! :biggrin:

x

 

[scorp965]

Install hood pins, you don't want to be the one who has 'issues', as the "issue" involves a hood flying straight into your windshield. I have yet to see a composite hood that doesn't flex, at least to some degree, over 100-120mph, especially a ventilated hood - of the hoods I have seen a large number use tapped composite material (eg fiberglass), replicating the factory under structure and using factory hardware - the vendors, including VIS (SOS), state pins are required for safety. Even if there is sandwiched metal threads it's still being held together by adhesive, and fiberglass.

Here is my marga hills hood, with hoodpins.com self-locking pins:

 

[4AU4LIFE]

I have this same hood. I've had it since 8-05. I put it on and promptly drove it on a road trip thru 3 states and ~1k miles over 4 days. When cruising down the interstate on unknown roads I noticed the hood was flexing a bit. Truthfully I was a little concerned about if it was going to break and come flying up but it never did. The max speed that I obtained was ~75mph so I wasn't REALLY testing it. Had no reason to.
That having been said, I do plan on getting the vent from SOS to help reduce the under car pressure to relieve it and reduce the amount of flex that it does have on highway speeds.
I spoke with several other owners that have this hood and other vented hoods and came to my own conclusions. You have to come to your own also.

 

[scorp965]

I am aware of two porsche owners who had an issue with (expensive, well made) composite hoods flying up in high speed conditions, why take the risk of injuring yourself, injuring others, totalling your car, or feeling uncomfortable about your hood, over something as trivial as hood pins?

cheap insurance, imho.

 

[4AU4LIFE]

I'm sure for whatever mod you want to do there are going to be people telling you to do or not to do it. They will have have their reasons for it and can/will come up with their own logic and facts to back up their statement. Ultimately, do what you want after you do research and are comfortable with your decision.
Afterall, it is YOUR car.

 

[VBNSX]

Here is my marga hills hood, with hoodpins.com self-locking pins:

Good product... actually gained my curiousity... that wouldn't be so bad..

unfortunately the availability is somewhat low...

x

 

[scorp965]

I'm sure for whatever mod you want to do there are going to be people telling you to do or not to do it.

An expert at saying nothing :tongue:

 

[02#154]

I've asked in a previous thread when this came up and nobody answered there. Hopefully I have better luck here.

The OEM NSX-R hood does not have hood pins. What sort of fastening setup is that hood running that makes it good enough to not have hood pins? Or should it have hood pins because the same issues exist on the OEM hood?

J

 

[evof575gtc]

the real NSX-R uses a pre-preg CF cured, baked, bagged in an autoclave to 8x's atmosphere pressure.

thats how you get a piece of carbon fabric as thin and paper but 10 times stronger than steel. you can try bending it all day, but it'll take more than a 200mph enzo crash to break it apart.

hoods made in someone's home backyard like the VIS one is dirty, simple and cheap to make. its called wet-lay up aka "dry-carbon"
instead of repeating, read a little bit of it below.

hey look what i found in our own backyard.
http://www.nsxprime.com/FAQ/Miscellaneous/carbonfiber.htm

some book stores have Racecar Engineering magazines.
theres lots of info there.

 

[evof575gtc]

if you want to buy hood pins.
buy them from me.

carbon fiber hood pins.
$30 a pair.
$40 shipped.

 

[evof575gtc]

I've asked in a previous thread when this came up and nobody answered there. Hopefully I have better luck here.

The OEM NSX-R hood does not have hood pins. What sort of fastening setup is that hood running that makes it good enough to not have hood pins? Or should it have hood pins because the same issues exist on the OEM hood?

J

not enough pressure to pop it up.
NSX-R has a huge gaping hole in it to release the air pressure.

or you can GET a VIS hood. the fitment is so terrible, the one inch gaps between the hood itself and the fenders reduces intaking air pressure and releases it through the horrible fitting gaps.haha

 

[710]

Nice pins.
But what are those black parts on your tan seats? I think they look nice, and since I am putting a tan interior in my car, I’m curious.
Do you have a close up picture of the seats?

 

[Bodhi]

Off thread but I think that the seats are aftermarkets covers from leatherseats.com. I have similar and they look great.. You can design a custom look with some fairly exotic fabrics.