Installing fiberglass rear quarterpanels instead of flares

[Shuie]

Are there any structural concerns when installing complete rear quarterpanels as opposed to just doing the flares. The only cars Ive ever seen with complete fiberglass quarters were full on racecars with cages and dzus fasteners holding the bodywork in place.

The thought process for installing the whole quarter is that the car has some damage outside of the flare area. Installing a complete fiberglass quarterpanel looks like it would be easier and cleaner than doing the flare and then fixing the rest of the rear body work.

Is using full fiberglass quarterpanels like the one below a bad idea for a mostly street car? Am I going to need to use dzus fasteners and tie a cage into the car to use these quarters, or can they be installed like the flares can?



(picture from www.rennspd.com)


Thanks!

[widebody911]

It would be interesting to see it done with the Dzus' I've considered the same thing for when my car become a full time track 'ho.

I don't see why you'd need a cage; you'd be maintaining the interior portion of the tub, so you're not losing a lot of crash protection.

As to cleanliness; if it's done right, nobody would know what you had under there unless you told them - look at Jack's car.

[Jack Olsen]

One important difference is that paint on fiberglass chips much more easily than on steel. If I just brush my paint with anything steel, I've got more touching up to do.

[Randy Webb]

I've hear that FG or CF tend to warp and pull away from the sheet metal tub over time (sounds a bit far fetched) and that they never look as good as steel.

[widebody911]

Originally posted by JackOlsen
One important difference is that paint on fiberglass chips much more easily than on steel. If I just brush my paint with anything steel, I've got more touching up to do.

Have you tried a flex additive?

[Avery]

I installed the full quarter panels on my car and they look great. You get a good amount of lightening in the rear. I do however think steel panels look smoother. As far as structural issues go, you really can't tell especially if the car is primarily streeted. Some of the original RSR's used FG panels.

[Shuie]

Thanks Avery. I dont mind dropping some weight from that area of the car at all. How far do the quarters extend? Do they go all the way into the recessed decklid support section of the engine bay? Its hard to tell in the pics Ive seen of them where the seam would be. Any chance you have some pics of the install on your car?

Im not exactly an artisan welder, so Im looking for the easiest and cleanest install option for the flares and remaining body work. Ive been looking at the steel flare sections as well. A set of flares is roughly the same cost as the quarter sections. I welded a new front suspension pan in the car without the front end of the car collapsing, but fortunately no will be able to see my work once the front fenders and bumpers are on.

[jpnovak]

I helped lay out a track 914 last weekend with GT flares for dzus fasteners. It was fairly easy. I will see if I can get some picts of the install from the owner. you basically scribe the line for the flare. Then cut about 1 inch inside the line with additional tabs every 8" or so for the fasteners. Simple install.

This car has a full cage that ties in susp. points. STiffness is not an issue. I imagine that a non-caged 911 would lose some rigidity in the rear end.

[Glasgow 911SC]

Does that panel include the door shut where the latch would be fixed? I never realised you could get these in fibreglass.

Might make sense to use this when repairing the rust damage like I had caused by snow and salt.

[dd74]

$325 a pair for those fenders sounds like a good deal!

[Avery]

My pictures files are too large. I'll have to send them to you via PM.

Felmir

[Shuie]

Thanks Felmir! I sent you a PM with my email address for the pics.

[Avery]

Here's a few pictures.

Here's the right side. All the white sections that you see is the FG panel. I cut out the steel panel with a cut off wheel. You can see that I also cut off the steel "water channel" that's located right under the right side of the deck lid. The FG panel that I had came with the water channel molded in. I used that molded water channel as a guide for locating whole panel. I lined up the channel perfectly square to the deck lid and then everything else lined up right. You can see the sheet metal screws within the channel that I used to initially hold the panel in. I eventually epoxied the panels in. I also retained the metal frame that holds the rear brake/turn signal lens.


And the left side...


I have many more pictures but my old PC is hosed and I'll have to get around to moving all my files to my new PC. The car is painted (ala BB2) and I have not noticed any problems yet with the FG panel. In fact it looks great in my opinion but time will tell if the FG holds up.

Felmir

[Jeff Alton]

Great pics.

Jeff

[Shuie]

Thanks Felmir, that helps a lot. Thats one of the sections I was wondering about. Do the quarters wrap around the door latch panel edge also? Do they extend into the rear quarter window frame as well?

[Avery]

The door frame where the striker is mounted stays intact. You cut the steel panel off about three inches from the edge of the door jamb and the quarter window. Since I haved a '72, I had to cut around the oil filler as well. The picture below shows approx location of the cut. The FG panel is bonded over over the remaining steel.


Felmir

[Shuie]

OK, I’m leaning towards the whole quarter sections. I searched some old posts and found that in general, tying a cage into the car was recommended when installing the full quarters.

New questions:
Is the cage only recommended for track work, or will it be needed to just to hold everything together for street driving? I’m obviously going to be more vulnerable to injury in a crash the back half of the body is fiberglass, what else am I risking? Are there other things I can do to strengthen the car to the point that I won’t need to use a cage to hold it together.

Thanks!

[collier]

Hey Shuie, are you looking for narrow body rears, SC rears, or ????

If you are looking for a set of narrow body flares, I might be cutting them off my 72 soon, in order to install the SC rear quarters that I have sitting here.

Let me know.

chris

[Shaun @ Tru6]

Thanks Felmir for the great pics and text. This is exactly what I will be doing in a GT-3S project if it ever warms up here in Boston. Just got a set of glass rear quarters, RS rear bumper and hood from Rennspeed today. Quality looked pretty good pulling everything out of the box. Quarters were incredibly light, hood was surprisingly heavy.

A few questions:

Did you reinforce the door striker panel with a few buttresses to the body?

What expoxy did you use for bonding?

I am thinking of going with dzus fasteners for ultimate access at the track, but epoxy may be an easier solution to get the car/parts/lines to all work together.

Thanks again.

Shaun

[Avery]

to answer Shuie's question about general body integrity, I've found to my relief that my car does not FEEL anymore flexible or "creeky" after I replaced the quarters and the front fenders with FG. My car is primarily a street car and it does not have a cage or roll bar. Any good Porsche should feel solid as a vault and I was happy that see that it retained that good old solid feel.

I did not re-enforce the door striker panel at all and the doors are closing just fine.

Here's a few pictures of the car prior to getting all the trim pieces back on. I think it came out great but any proud pappa would say that.