Jim M.

Roger if you chose to market these, you can put me down for a set. Urathane sounds like the answer!

worf928

On my side of the fence, I'm totally OK with an early '10 delivery. I'll put my name down for at least one set of GTS liners. I expect to need two sets but won't be sure for a couple of weeks.

Like the rest of the folks - I want replacements that will last.

Also, remember that the liners need to be able to deform to get them in and out of the wells. Normal fiberglass won't work too well.

Last, the left-side liner has to come out at least once every two years to service the PSD (for us folks with normal-sized forearms. Alien E.T. types can work through the inspection hole.)

Jerry Feather

Thanks Gary for posting my email about this project. I have done a lot of designing on this project without the benefit of the pictures that have been posted. It helps a little to look at them, but unfortunately my mind has taken off on its own and has been busy designing these Wheel well liners independently of the originals.

What I did was take some tentative measurements off the wheel well area of one of my cars and then begin a process of designing how these would be made. From the shape of the originals it is clear that in order to exactly duplicate them, or pretty near, two molds or form would need to be made, one of each side, and then if they were to be blown in ABS plastic, as I will try, they would each have to be blown seperately.

My first design was the blow the basic shape all in one form, getting two liners together and then glueing them to seperate inside surfaces making them each in two pieces.

However, there is a significant limitation to this method and that is that the liners blown from one set of forms would make liners only for one of the cars or one of the car widths.

I take it that the GTS is quite a bit wider in the rear that my S4's. Now I am hearing that maybe the GT cars are also wider, but maybe not as much as the GTS? Can anyone tell me , and by how much each is wider than the S4?

In any case, the main question now for me is just how different the wheel opening is on thes cars with the wider rear. I suspect that the side view of the wheel arch is pretty identical to all the cars, but what I don't know is how different the body curvature is in that area. In other words, when the quarter panels were widened, did they simply move the wheel opening straight outboard or did they rotate it so that the bottom is still at about the same place and the top is just farther out?

This is important because it bears on the prospect for me to make wheel well liners that can be adjusted to fit any of the cars and with just two sets of forms--one for the inner half and one for the outer half. With these they can be overlapped along their circumfrence just the right amount to suit the particular car and it's wheel well width. I may need to see some of the cars close up in order to tell.

What I am going to do is make a form of the wheel wells on one of my S4's and I can then use that to compare on the other cars when I can get in their proximity. In the mean time I am going to start with a basic circumfrence form for the liner itself and then start working on the overall shape. I haven't started with any materials yet but am working on the design of the forming machine that I am going to call the blow oven. That is going to take some welding and aluminum fabrication and some exectrical work for the oven coils.

I am going to do it a little at a time right now while I am finishing up the development of the 928 Hatch Latch Receiver Liner that I have been working on the last couple of weeks. That is nearing completion and I will have a substantial number of the latch liners finished this week. I hope there is enough interest in them to make it worth my while to have developed them.

Thanks again, Gary, and the others for the pictures and for your support. I'll try to stay in touch as I progress. When I have some pictures, I'll try to post they also.

Jerry Feather, FBA Certified
S4's (6)
KGJT

Jerry Feather

Just so you know where I am and where I am going with this liner project I thought I would try to give you a word picture of my current concept as follows:

I am going to make these liners by using a blow forming process using ABS plastic about 3/32 inch thick to start. in the blowing process the plastic will stretch out, but not much. I doupt that the thickness will reduce to 1/16 inch, and if it does it will only be in certain locations.

The liners will fit snuggly inside the perimeter of the wheel opening and will have a reinforced edge and slight flange. The reinforcement will likely be a rod of ABS either 1/4 inch or 3/16 inch ABS glued in place.

The liners will be in two parts. The outer part and the inner part. The outer part will be formed in one form which will make both sides. The blow will be about 8 inches deep which will allow enough overlap to accomodate any of the car widths. This side of the liner will be fairly simple with smooth curvature from just above the wheel opening in a radius of about 2.5 to 3 inched and then over the top perpendicular to the car.

The inner half will also be blown in one piece for left and right. It will be a little more complex, but much the same as the outer. Its inner surface will conform to the inside of the wheel well and the frame/body structure there. I may even put the little zig-zag design along it like on the frame part of the car. There may need to be some forming around plumbing and/or wiring, but that is just a detail.

The advantage of having two pieces is first to accomodate more or all of the cars. and another is to facilitate installation and renoval. The liner will come out in two pieces and will not need to be severly deformed to remove. The two halves will be fastend together with door panel clips unles I can come up with a better form of temporary fastener since these clips are sometimes hard to pull out.

On the inside half on the surface next to the car I plan as an option to cover them with sound absorbing material that will be glued on permanently. I may put some on the front area of the outer liner also.

I haven't finished the design of how these will be affixed to the car, but I am working on that--probably three or four screws along the frame andone or two in the front and rear bottom areas. The rest will simply be pressure against the rim of the wheel arch.

The ABS Plastic has a pebble finish on one side and a smooth surface on the other. I'll form these liners with the pebble finish on the tire side because that is the best looking finish. TGhis plastic comes in balack and white. I doubt that anyone would like a white liner, but that might be to best to form for someone who wants to paint their something different than black.

Does that give you a decent mental picture of what I have in mind?

Jerry Feather, FBA Certified

S4ordie

Greg and Roger, I am happy to donate/sacrifice the set I purchased a few months back in exchange for two urethane sets. However, I am concerned the ones I orded may be like the ones a few people have ordered previously. Meaning are they the right size for the GTS? Seems Porsche has some issues with the part numbers.

Greg, do you have a GTs you could trial fit them on before they are used for the molds? Might be worth the headache to make sure they are correct in dimensions.

S4ordie

Jerry Feather - what does FBA Certified mean? Also, I'd think the smooth surface would be easier to clean than the pebble finish. Does it make sense that the tire side of th eliner should then be smooth?

Rob Edwards

I took some rough measurements off the GT and the GTS, using a tape measure, and measured from the inboard rail, assuming that the rear inboard frame rail is a planar surface (close enough assumption for quick and dirty measurements. These are not super accurate, but hopefully informative.)


Anyway, the contour of the wheelwell opening is significantly different btw the two. Not sure how wide the GT wheelwell is at the top of the arch (tire was in the way), I'll jack up the car and get a measurement at some point.

EDIT- Mkay, so this just verifies what Big Easy's pics of the new factory liner mounted in his GTS show- fit is ok foreward, not ok at the top of the arch and aft.



Rear of GT vs GTS wheelwell:

GT (11-3/4in):


GTS (12 in):



Front of GT vs GTS wheelwell: I think the GTS is maybe 1/2" wider at this point (?) Will have to measure again with a straight edge, more carefully)

GT:


GTS:


Top of GTS wheelwell:

Jerry Feather

Thanks, Rob, for going to the effort to take these measurements and post them. They are very helpful and when I get to compare them with the S4 tonight I'll have a good idea about how much wider the Gt and GTS cars, but more importantly I think I'll be able to tell that the wheel wells are farther out parallel to the narrower cars rather than being rotated out from the bottom. Parallel is going to be much better, but I think some rotational change can also be accomodated with my two part design for these liners.

Jerry Feather, FBA Certified
S4's (6)
KGJT

Gary Knox

I may be wrong, but I don't think there is any difference in the rear quarter panel wheel well width between the S4's and the GT's. It is my opinion that Porsche made the liners for the '91 cars, then just continued to use the same ones with the GTS's with their 3/4 inch wider wheel well/wheel offset. The liners in my '94 GTS do not come out to the edge of the fenders, but terminate about 3/4 inch in from the edge!

Just my observation!!

Gary Knox

Jerry Feather

Dan H.

I think that the liners I have in mind can be formed either way. I think that either side of the plastic will clean just as easily. However, the drawback to the smooth side in, is that the plastic is soft and will scratch easily and so that shows very readily. I suppose the pebble side also scratches, but it doesn't show so much. On the other hand, for someone who wants something closer to the factory finish they could take steel wook to the inside with the smooth finish and give it a very dull or flat finish. I suppose that coud be done to the pebble side too. Then they are going to be even tougher to clean, however.

I woud predict that if I were to form a set of these with the smooth side in when compared to the pebble finish that set would never sell.

Thanks for your suggestion. Do you have any thoughts about the two part concept? Do you have any thoughts about the idea that these will not be a duplicate of the originals?

Jerry Feather, FBA Certified
S4's (6)
KGJT

heinrich

Jerry, some thoughts:

1) don't add insulation or patterns. Complication is your enemy
2) don't bother with sound deadening. I would like to instal my own deadening choice. This will also lower your price.
3) price is really important. Save on manufacturing so we can save per unit and thus sell more units. Remember, relatively few owners need these
4) The only owners who need these, will be GTS (and the few earlier cars that have GTS panels)
5) there were only two fender sizes: early and GTS
6) 2-piece is ok but 1-piece is preferable. 2-piece will deform later-on and water/mud/SALT will get in and that is bad.

Rob Edwards

Maybe this is why the liners disintegrate so rapidly, if there's a 3/4" gap at the top that lets sprayed moisture up onto the top of the foam backing and rots it out ? Maybe not, as the '91 liners sound like they rot too, but it certainly can't help.

OTOH, if you made a liner with an increased 'flare' to fit out to the lateral edge of the GTS fender at the top, wouldn't they be a beyotch to fit in place?

dprantl

The rear liners on my '91 GT are terrible. If I sneeze too close to the car a piece falls off. The front ones look great.

Dan
'91 928GT S/C 475hp/460lb.ft

S4ordie

Thanks for that insight Gary. This is what I was referring to. There have been previous reports of the liners not fitting very well on the GTS. If the liners are the same as the ones for the 91 S4/GT this explains the gap, which is not good.

Heinrich - though the liners were not produced until 91 they should be applicable to all 87-91 cars. I would think many would buy these for their 87-90 S4/GT's if they were available as they should fit the same. This would increase demand and lower cost.

Jerry this would mean either making a separate mold for the 87-91 cars and another for the GTS, or, make one size that fits the GTS with the ability to trim it down to fit the more narrow 87-94.

heinrich

I like Dan's trim-down idea. Rob ... fit it once just like the front liners on the S4 and it stays there forever. WHo cares as long as it keeps salt and water out of the PSD, fuel filler area and other places where it could cause issues.