Backdate Issues

[BlueHorizon]

Working with my metal shop guy to do some rough fitment of a 911 ST backdate kit onto my 1980 SC. Specifically we are using the ST kit from Design 911 which, besides the front modifications, should fit on my year vehicle. Or at least so we thought!

Anyway, we are running into issues trying to get the fenders into a decent position. Take a look at the images attached. You can see that the fenders (which are the 69 - 73 type) are not aligned at all with the doors / sill. We have the scuttle panel rubber although even those would not correct where the fender lies.

I've reached out to Design 911 to get some help but, while we await a response, thought I'd drop a note here to make sure we aren't missing anything obvious.

Thoughts?

[salayc]

I'm doing the same with Porsche factory parts right now.
Make sure that all of the sealing tape from the old fender is removed (sounds obvious but...) or perhaps you're hanging up on your gas filler?
The bottom of the fender could be gently persuaded to align once bolts are attached.
Could be the pictures, but it looks like the fender is sitting lower at the front, meaning it's tilted downwards back to front.

[BlueHorizon]

Thanks Salayc, right now the fender is bare and so is the body so there's no tape left anywhere. The other thing I noted is that the bolts don't line up nicely between the body and the fender. Could be an issue with it being non factory parts?

[salayc]

Originally Posted by BlueHorizon

Thanks Salayc, right now the fender is bare and so is the body so there's no tape left anywhere. The other thing I noted is that the bolts don't line up nicely between the body and the fender. Could be an issue with it being non factory parts?

I mean, the fender doesn't even look close. So if it's not hanging up on something, or your chassis is not out of alignment, I'd say there's a problem with the fender. The bottom edge really looks off where it meets the rocker.

[dwelle]

check the clearance of the tube for the gas door pull against the fender. i had issues w/ mine when i backdated my green car...

[Arlo911]

Did you remove the front bumper supports yet? The new fenders might need some slight work to align properly with the scuttle panel but not this much? Maybe post a picture with the fender removed.

Same thing on the passenger side?

[Dpmulvan]

Originally Posted by Arlo911

Did you remove the front bumper supports yet? The new fenders might need some slight work to align properly with the scuttle panel but not this much? Maybe post a picture with the fender removed.

Same thing on the passenger side?

+1 you need to chop off bumper shock mounts because they interfere with signal frames. Some pics would be good of front.

[dwelle]

i didn't cut my bumper shock mounts. if i recall, i had to trim the fender a bit.

the only cut i made to the car was removing the rear tow hook receiver...

[AirJose]

Hello all,

salayc comments are good, the bend in the fender should align with the body, maybe we can't see from the top. All holes must align. Fender should have adjustment slats. Do you have any shims between the hinges and the cowl? How the gap looks in the rear/ (door lock to body) should be 3-4mm

Jose

[BlueHorizon]

Thanks for the comments everyone. We did cut off the impact bumper pieces on the front so those shouldn't be interfering at this point.

I don't have photos at hand as the car is with my metalshaper and, with the social distancing situation, I can't easily snap pics. I've asked if he can join in and share some photos.

[salayc]

Where are you located?

[BlueHorizon]

Austin, TX

[salayc]

Originally Posted by BlueHorizon

Austin, TX

Too bad, if you were local I'd come by with a fender. Maybe someone can help out.

[BlueHorizon]

Much appreciated - sure you don't have time for a roadtrip? :-D

Seriously though, will wait for Edward (metalshaper) to get on the forum by Monday and he should be able to provide more photos and details to see if we can figure this out.

One thing he and I did discuss is the idea of getting "modern" fenders that would have fit the G body style previously (note that I don't have the originals) and then perhaps cutting out the lower front part of the 69-73 fenders where the lighting is and merging these with the modern fenders. Would that seem crazy? I'm fine with this approach as Edward is a master with metal although it would involve dropping more money on new style fenders which is a shame as the 69-73 ones are new.

Edit: You can see some of Edward's work via instagram as he builds panels and body parts for everything from very early Bugattis to 356 Porsches : https://www.instagram.com/extraordinary_metalshaping/feed/?hl=en

[salayc]

Looking at his work, he should have no problem welding the front of the fenders. Take a look at what TRE offers: https://tremotorsports.com/exterior/steel-backdate-conversion-turn-signal-boxes
I'd be concerned other fenders would have the same problem though. How's the passenger side?

[tperazzo]

Any panel fitting on a classic car will need some massaging to get the gaps and fitment right on these cars.

Even when these cars were new the factory had tricks to align stuff, shims, sealing puddy, lead, big hammers, etc.

I found some heavy hammer marks on my car when my shell was totally stripped down. A few hits right where the fender attaches to the tub. That fender had never been removed from my car so I believe the factory knew exactly where to adjust without being visible.

Sounds like you have an expert available to assess. This is why these guys earn their money. In my opinion this is totally normal and a needed skill for a backdate.

[coomo]

I live 2 miles from Design 911.generally they are good guys.However, most of the team are just order takers and any experience isnt Porsche related.
You have bought a "kit" that will consist of Dansk panels.Most of the guys in UK I know who professionally build 911s will only use them (Dansk) for specific panels.Ok for inner sills(rockers) yet always use Genuine For outer rockers.Yes, they will fit but im sure the presses which stamp these are not in good tolerance anymore.
Ive just bought a load of panels from Resto design where fit is critical, only Dansk for rockers, kidney bowls rear panels etc.
Im sure your guy will be able to panel it well.Good luck.

[Fixer]

That area on the door above the mirror changed very slightly over the years, that is common.

You can add lead there, that is a quick and forever fix.

The rest of that poor gap is pretty easily tightened up the old fashioned way. There is tolerance in the fender bolting to make it work.

The best way to back-date is use your fenders like I did. In the end itll take less time.

Regards

Matt

[Arlo911]

Originally Posted by BlueHorizon

Much appreciated - sure you don't have time for a roadtrip? :-D

Seriously though, will wait for Edward (metalshaper) to get on the forum by Monday and he should be able to provide more photos and details to see if we can figure this out.

One thing he and I did discuss is the idea of getting "modern" fenders that would have fit the G body style previously (note that I don't have the originals) and then perhaps cutting out the lower front part of the 69-73 fenders where the lighting is and merging these with the modern fenders. Would that seem crazy? I'm fine with this approach as Edward is a master with metal although it would involve dropping more money on new style fenders which is a shame as the 69-73 ones are new.

Edit: You can see some of Edward's work via instagram as he builds panels and body parts for everything from very early Bugattis to 356 Porsches : https://www.instagram.com/extraordinary_metalshaping/feed/?hl=en

No need to cut and merge old and new fenders, the ones you have should fit and only need minor adjustments, the problem IMO is not with the fenders unless you received a bad one, but this can be checked and measured using the old fender.
On a backdate the difference is only at the front of the fender (turn signal housing)

[Edward - EMS]

Hi everyone!

I'm Edward, the metal crafter who has been working on BlueHorizon's 911.
Below are additional pictures showing the fitment of those fenders.

There is no rubber or sealing tape, everything is bare. The left fender is not hanging up on the gas door. Both bumper shock mounts got removed. Both door fits well. Gaps are nice, even and consistent. Chassis got straightened within a 2mm tolerance on a overall diagonal length.

One of those additional pictures shows the alignment between the fender's speed nuts and the body holes on the trunk side panels. But the spacing between the speed nuts (installed at the right locations) on the fenders doesn't match the body holes making just almost impossible to move the fender around. I could oval the holes, but that will not improve the fitment as much as it needs...

The shape of both fenders just don't match the shape of either doors nor the left rocker panel. Plus, the fenders are not identical from one to another. The left one appears the be too short to meet the rocker panel and the right one, even though looking better, still has some major contour issues with the door and the cowl.

Even if we'd try and force the fenders into place, it just wouldn't fit right.
To me, they just look wrong for the car...

UNLESS there is something we don't see or know that you guys do??

(we thought about using original fenders and graft into them the "modern" turn signal housings so we could have the style we want. But if there is anything we can try before doing any surgical work, we're all up for it.)