Fixes for headlights popping up at speed? (Page 1/2)
1985 Fiero GT JUL 14, 01:26 PM
I know all about all the various hood vents people install, but I was curious, if the issue is just radiator air catching in the front end and building pressure, why not just seal off the radiator section from the headlights section, either use some plastic to create a smooth transition running all the way from the top of the radiator down, sealed on the sides, or have 2 "walls" extending up on the insides of the headlights, with rubber seals to seal against the hood like the frunk has. Any other ideas on improving the front end aerodynamics? Has anyone incorporated vents into the headlight covers (maybe the only vent mod I might consider, if it were to a second set of headlight doors).

Also I'm not driving these speeds at all, but I do plan to take it down an unused runway at Loring AFB sometime (where they hold land speed competitions) see what it tops out at, and I definitely don't want my headlights popping up, of I don't change anything, I'll just do it with the hood popped.
Patrick JUL 14, 01:54 PM

quote
Originally posted by 1985 Fiero GT:

I know all about all the various hood vents people install, but I was curious, if the issue is just radiator air catching in the front end and building pressure...



I would say the vast majority of us who've installed hood vents, have done so in order to increase the cooling ability of the radiator, not to prevent the headlights from popping up at illegal speeds.
1985 Fiero GT JUL 14, 02:01 PM

quote
Originally posted by Patrick:

I would say the vast majority of us who've installed hood vents, have done so in order to increase the cooling ability of the radiator, not to prevent the headlights from popping up at illegal speeds.



Perhaps, but every thread I see about people's headlights popping up at speed, everyone's talking about adding a hood vent to solve that, as well as for reducing front end lift at those speeds. As for the speeds being illegal, that's only if you do it on a public road with a speed limit, on a private runway, literally used for official land speed competitions, there's nothing "illegal" about that. As I said I have not gotten anywhere near those speeds, most I've done is 20 over, with the rest of traffic flying by me at another 20 above that, and that was only for a few minutes until I realized I was speeding, then I slowed down.
cvxjet JUL 14, 02:24 PM
Back 15 years ago, the paint on my Fiero upper surfaces was dying- parked outside it's whole life. So instead of painting it ($2000) I grabbed some upper surface body parts from the JYs ($500)....Installed the hood; driving home from work one day I got it up to approx' 80 mph and the headlight doors suddenly popped up.

Examined the two hoods and noticed that the original hood had TWO torsion-bar springs on each headlight door, while the "new" hood only had one per door. Added the extra set to the new hood and have actually had the car up over 100- in a headwind- and the doors do not pop up.
IMSA GT JUL 14, 02:44 PM
Sorry for the crappy pic but I had to enlarge the only one I could find. People add vents to the headlight buckets and they supposedly work great.
1985 Fiero GT JUL 14, 02:45 PM

quote
Originally posted by IMSA GT:

Sorry for the crappy pic but I had to enlarge the only one I could find. People add vents to the headlight buckets and they supposedly work great.



Ok, interesting, I vaguely remember reading about those, thanks for the pictures.

[This message has been edited by 1985 Fiero GT (edited 07-14-2024).]

theogre JUL 14, 02:51 PM
May have Nothing pushing door from bottom but simple air over the top causing low pressure then cause Aero Lift even a little "sucking" up the door enough then wind load does the slamming door problem.

Believe RD made "leashes" for this.
They use small cables to tie the front of door to the lift when down to keep door down.
Believe also problem is can't open the hood w/o opening the doors if too tight.

So Maybe the cables just stopped doors flying open all the way.

Other times, the doors have broken/missing spring on the bottom of the assembly & way easier for slamming problem.

For racing, just install something to Lock the doors down & disable the motors so they won't get wreck while door are Locked.
Frenchrafe JUL 14, 04:54 PM
I only get headlight door pop when drag racing.
Never got it on a trackday? Maybe not exactly the same speeds or car dynamics...?
Well, whatever, I "fixed" the problem by drilling and fitting two removable pins that effectivly block the door hinges on a race day. (I also disconnect the motors for the day so as not to accidently operate the headlights.)
------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. - The fastest Fiero in France! @turboslugfiero
https://youtu.be/hUzOAeyWLfM

[This message has been edited by Frenchrafe (edited 07-15-2024).]

Patrick JUL 14, 06:00 PM

quote
Originally posted by 1985 Fiero GT:

Perhaps, but every thread I see about people's headlights popping up at speed, everyone's talking about adding a hood vent to solve that, as well as for reducing front end lift at those speeds. As for the speeds being illegal, that's only if you do it on a public road with a speed limit, on a private runway, literally used for official land speed competitions, there's nothing "illegal" about that.



How many of us are driving "on a private runway" on a regular basis? Almost zero, I estimate... so headlights reported to be "popping up" are probably occurring while the car is being driven at an "illegal" speed if on a public highway. I'm not criticizing or chastising anyone. I'm just making the point that in regular day to day driving, Fiero headlights do not pop up. However, installing hood vents to help keep the engine cool is something that pays dividends each and every day of normal driving... especially in the summer!

I've used this hood on three different Fieros (so far)...

CLICK FOR FULL SIZE

[This message has been edited by Patrick (edited 07-14-2024).]

da.slyboy JUL 15, 02:16 PM

quote
Originally posted by IMSA GT:

Sorry for the crappy pic but I had to enlarge the only one I could find. People add vents to the headlight buckets and they supposedly work great.



I'm looking to do this mod after I lost my headlight covers due to a semi (on a windy day going while driving about 65mph) passing me in the opposite lane. I've seen the vents placed on the bottom of the bucket, wonder if more effective on the side?