Dip at front of the frunk lid - Why?
04-12-2021, 08:03 AM
#1
Dip at front of the frunk lid - Why?
Hi All,
I keep spotting (including my own black 997.1) that all 997's have a slight dip (or rather it looks like it should be but is a more a distortion) running the entire width from the top of the badge to the frunk lid lip (the bit that aligns with the bumper). ps: i am not talking about the frunk being lower than the bumper.
Initially I thought it was just bad closing technique of the frunk but it was just too consistent, then you see it's the same on every 997.
Sometimes you do have to look for it (and only on a perfectly clean car) by moving your head side to side and then you will notice the reflection slightly distorts at that bottom bit.
I had read on here that it was something to do with aerodynamics, but does anyone actually know?
I keep spotting (including my own black 997.1) that all 997's have a slight dip (or rather it looks like it should be but is a more a distortion) running the entire width from the top of the badge to the frunk lid lip (the bit that aligns with the bumper). ps: i am not talking about the frunk being lower than the bumper.
Initially I thought it was just bad closing technique of the frunk but it was just too consistent, then you see it's the same on every 997.
Sometimes you do have to look for it (and only on a perfectly clean car) by moving your head side to side and then you will notice the reflection slightly distorts at that bottom bit.
I had read on here that it was something to do with aerodynamics, but does anyone actually know?
Last edited by v6matt; 04-12-2021 at 03:10 PM.
04-12-2021, 11:40 AM
#2
Rennlist Member
OP - You mean the dip to just below the bumper cover? Same on the 996. Hood lip below the air coming off the bumper cover reduces drag by not disrupting airflow as the air stays attached to hood around the badge. If the hood matches bumper seam level, a burble disrupts the flow at the gap, causing the air to “tumble” and adds drag. Part of the reason these cars have Cd’s below .29. Note the shadowing on my 996 at the bumper cover seam.
Last edited by hatchetf15; 04-12-2021 at 11:41 AM.
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vg247 (04-13-2021)
04-12-2021, 01:07 PM
#3
OP - You mean the dip to just below the bumper cover? Same on the 996. Hood lip below the air coming off the bumper cover reduces drag by not disrupting airflow as the air stays attached to hood around the badge. If the hood matches bumper seam level, a burble disrupts the flow at the gap, causing the air to “tumble” and adds drag. Part of the reason these cars have Cd’s below .29. Note the shadowing on my 996 at the bumper cover seam.
What I mean is the area between the top of the badge, down to the bottom of the frunk (i.e where it meets the bumper)
You can see here the panel reflection distorts a little bit
04-12-2021, 01:13 PM
#4
Three Wheelin'
Perhaps it is from the dropping/slamming the frunk lid to close? I've seen Porsche service do it and I cringe every time. The lid can bend very easily if you overfill the compartment and accidently close the lid over it. I've seen that as well too.
The correct way is the support the lid and lower it until it catches the striker. Then push it closed with your palm on the emblem until it clicks.
The correct way is the support the lid and lower it until it catches the striker. Then push it closed with your palm on the emblem until it clicks.
04-12-2021, 01:24 PM
#6
Perhaps it is from the dropping/slamming the frunk lid to close? I've seen Porsche service do it and I cringe every time. The lid can bend very easily if you overfill the compartment and accidently close the lid over it. I've seen that as well too.
The correct way is the support the lid until it catches the striker and then push it closed with your palm on the emblem until it clicks.
The correct way is the support the lid until it catches the striker and then push it closed with your palm on the emblem until it clicks.
On lighter cars (but easier with dark cars) and they have to be clean, if you focus on that area and move your head to the left and back, you will normally see it.
Particularly keen to check I am not going insane, as I will likely be giving the front end a refresh soon and don't want to have it pulled out if that is 100% factory which it seems to be.
Last edited by v6matt; 04-12-2021 at 02:34 PM.
04-12-2021, 02:10 PM
#7
This is not the lid bending or being damaged. The seals are set in such a way as to require the lid to be as low as it is. Adjusting it differently could result in rain or wash water leaking in.
View it in a slightly different way ... Would you want the lid to be higher than the bumper and take the wind load and possibly blow open if the latch failed?
As previously mentioned, a bit lower is an aerodynamic decision. It reduces the CD.
A note on closing ... I have heard many say close softly and then push on the emblem. The first part is correct. But the emblem is behind the latch and pressing here puts strain on the aluminum hood. Press directly where the latch is to avoid crimping the metal.
View it in a slightly different way ... Would you want the lid to be higher than the bumper and take the wind load and possibly blow open if the latch failed?
As previously mentioned, a bit lower is an aerodynamic decision. It reduces the CD.
A note on closing ... I have heard many say close softly and then push on the emblem. The first part is correct. But the emblem is behind the latch and pressing here puts strain on the aluminum hood. Press directly where the latch is to avoid crimping the metal.
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vg247 (04-13-2021)
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04-12-2021, 02:23 PM
#8
This is not the lid bending or being damaged. The seals are set in such a way as to require the lid to be as low as it is. Adjusting it differently could result in rain or wash water leaking in.
View it in a slightly different way ... Would you want the lid to be higher than the bumper and take the wind load and possibly blow open if the latch failed?
As previously mentioned, a bit lower is an aerodynamic decision. It reduces the CD.
A note on closing ... I have heard many say close softly and then push on the emblem. The first part is correct. But the emblem is behind the latch and pressing here puts strain on the aluminum hood. Press directly where the latch is to avoid crimping the metal.
View it in a slightly different way ... Would you want the lid to be higher than the bumper and take the wind load and possibly blow open if the latch failed?
As previously mentioned, a bit lower is an aerodynamic decision. It reduces the CD.
A note on closing ... I have heard many say close softly and then push on the emblem. The first part is correct. But the emblem is behind the latch and pressing here puts strain on the aluminum hood. Press directly where the latch is to avoid crimping the metal.
The question wasn't so much about the frunk being lower than the bumper (that is normal I knw), it was the fact that the frunk metal seems to be dipped in slightly in that highlighted area which means reflections on that part of the panel look a little odd. In the same way that if you have a dent on the door the light curves around the dent oddly. Something like that but to a much lesser degree.
Maybe that's part of Porsche's design to dip that front bit a bit lower, so it sits under the PU (in conjunction with the seals/adjustments being set to that position)
EDIT: I just went outside and felt through the hole (oh er!) and there is a reinforced metal sheet welded to the back of that exact bit. I suspect this is what is causing this very slight distortion and explains why it is so consistent across the panel. It must be there to add weight/reinforce the front part of the frunk
Last edited by v6matt; 04-12-2021 at 03:04 PM.
04-12-2021, 03:04 PM
#9
Rennlist Member
I just looked at my car and there’s no dip in the front of the trunk lid. There’s also no distortion of the reflection at that section of the hood.
04-12-2021, 03:09 PM
#10
I just found by poking my finger in the hole that there is a welded panel to the back of that exactarea (through the round holes on each side (UK car) and I bet it's that.
My wife can't see it, but I can. I think I will pop to a local 911 specialist and have a chat with them to make sure it isn't just my local cars, but I think I have found what it is!
Some more examples of it (having a quick look around my local used car pages)
https://m.atcdn.co.uk/a/media/w1024/...e716c59cd3.jpg
https://m.atcdn.co.uk/a/media/w1024/...3cf8152eef.jpg
https://m.atcdn.co.uk/a/media/w1024/...058a03864f.jpg
https://m.atcdn.co.uk/a/media/w1024/...ceaa363623.jpg
Last edited by v6matt; 04-12-2021 at 03:34 PM.
04-12-2021, 03:33 PM
#11
Rennlist Member
That's interesting, it's not so much a dip (I know I called it that) but it's more a slight distorted reflection . You do need a completely clean panel and you need to stand back and walk from side to side looking at the same sort of spot. I am a bit OCD with bodywork so I spot every defect very quickly (it's a curse!). Still can't see it?
I just found by poking my finger in the hole that there is a welded panel to the back of that exactarea (through the round holes on each side (UK car) and I bet it's that.
My wife can't see it, but I can. I think I will pop to a local 911 specialist and have a chat with them to make sure it isn't just my local cars, but I think I have found what it is!
I just found by poking my finger in the hole that there is a welded panel to the back of that exactarea (through the round holes on each side (UK car) and I bet it's that.
My wife can't see it, but I can. I think I will pop to a local 911 specialist and have a chat with them to make sure it isn't just my local cars, but I think I have found what it is!
04-12-2021, 03:36 PM
#12
You need to go back a probably at least a 2 metres and look in natural light, you wont be able to see it without full light and stepping back from it, it will appear completely right up close. Take a look at a few of the examples I just posted above. It might just be the light or of course, I might just be wrong !
04-12-2021, 03:42 PM
#14
Here is another one, of the 20 odd cars I looked at pictures of. I could see in the pictures 10 that had it, the others either weren't visible due to I guess either not being there, or the wrong angle. Most of my photos wouldn't show it, I would have to purposely angle the camera and have something like a cloud or tree reflect so I could see it.
Here is another!
https://m.atcdn.co.uk/a/media/w1024/...93fb30ac7b.jpg
04-12-2021, 03:43 PM
#15
Rennlist Member
You need to go back a probably at least a 2 metres and look in natural light, you wont be able to see it without full light and stepping back from it, it will appear completely right up close. Take a look at a few of the examples I just posted above. It might just be the light or of course, I might just be wrong !