Is it possible to get a decent door gap on the latch side?

[FFRWRX]

Let me add something to that title..."without a lot of fibreglass work".

I haven't spent a lot of time on the car lately, but trying to get back to it now. One problem is that after spending hundreds of hours on the doors (including the door windows), they still fit like crap. I can't see that I've done anything wrong, but how do you get around this:

Screen Shot 2022-07-12 at 6.34.28 PM.jpg

The door gap is reasonable here. This is about Honda Civic gap, so nothing to brag about, but pretty good. My wife's Civic was right beside me so I did a quick check.

But when the door opens, I get hard rubbing of the door skin on the body:

Screen Shot 2022-07-12 at 6.34.50 PM.jpg

The door skin is too thin to grind anything more off it. So the only solution, without major fibreglass work, is to increase the gap to eliminate the rub. True?

The driver's side is worse. I need a gap of about 1/2" to eliminate any rub when opening the door; allowing just under 1/8" clearance when opening to allow for movement and paint. That's ridiculous!

I could open the gap to that amount, then build up a fibreglass lip on the outside of the door panel to reduce the visible gap. But I really don't want to get into that.

So please tell me I'm doing something wrong. Please tell me that F5 has improved doors since I built my first Cobra from them over 20 years ago and struggled with the doors. Please tell me that they haven't designed a door where the gap disappears as the door opens.

Thank you,

Rick

[lance corsi]

Rick, the doors actually fit ok, the problem arises from the door catch loop which you’ve taken from the donor car. The configuration of the doors keeps the striker too far from the latch mechanism. I made new catch loops about 3/16” longer than the originals. It works well. It’s a bummer that there are so many small things to correct on this car.

[FFRWRX]

But that wouldn't affect the door gap. Even if I took the latch off I'm still going to have this issue.

I just did a little more investigating and thinking. I've concluded what I originally thought....F5 does not know how to design doors and door windows.

Check this picture:

Screen Shot 2022-07-12 at 7.39.35 PM.jpg

This is looking down onto the hinge at the front of the drivers door. See where the pivot point of the hinge is; it is 3" outwards from the inner surface of the door (from the left side of that aluminum piece that is the inside of the door). The left side of that aluminum piece is roughly where the inside of the door is at the latch end. So I did some quick modelling and what you see is that the gap at the inside of the door at the latch side reduces as the door opens. It has to due to the geometry of the hinge mechanism. If the pivot point were at the inside of the door (ie, move it to the left in the picture about 3") then the door gap would not change as the door opens and closes. Does that make sense?

Have I possibly assembled the hinge wrong? I did buy my car partially assembled, so could use that as an excuse.

I think if I could modify the hinge to move the pivot point closer to the inside of the door (moving it left in the picture) it would eliminate this issue. Not moving any part of the door, just the hinge pivot point.

Thoughts?

Rick

[Ajzride]

I’m going from memory and some different angles shots on my build thread, but your hinges look way different than mine.

[lance corsi]

Rick, you are correct in your assessment of the doors. Because of the hinge placement, the door edge had to be angled for the door to close. Car doors are supposed to overlap the body. This helps with side impacts and gives a interface to install a door seal. Ffr doesn’t know how to design doors or windows as demonstrated by the 33, the gtm, and of course this car.

[FFRWRX]

I’m going from memory and some different angles shots on my build thread, but your hinges look way different than mine.

I just checked the build manual (you know, when all else fails) and the pictures look exactly like mine and assembled like mine. I'm figuring out how to move the hinge so the pivot is much closer to the inside of the door without a huge fabrication and welding project.

[cob427sc]

Not sure whats going on with your doors but my 818 was started by someone else and the door gaps are less than 1/8' after paint. Everything worked fine until I installed the interior door panels which then made the door surface drag against the rear door post. I changed out the screws holding the interior panel in and used tapered head screws. I got the drivers door working perfectly and had to adjust the passengers side by sliding the door forward about a 1/16". Gap still only about 1/8" and no drag.

[FFRWRX]

Not sure whats going on with your doors...

A bit more thought and investigation and here is what is going on.

The analysis I did is correct. The door gap, measured at the inside of the door at the rear does reduce as the door is opened. So I wondered how your gap could be good. Then did another quick look at my doors and have the answer.

This is a picture of the driver's side door at the back looking down. You can just see the latch area at the upper right.

Attachment 169515

That is a square that I'm holding against the outer part of the door panel. Notice the 1/2" gap? So I need a minimum 1/2" door gap at the outside and even then the inner part of the door skin will be rubbing the adjacent part of the body. Talk about a poor job of molding! If that is less than 90 degrees, as it should be to work properly, then it would be OK. The hinge geometry is still wrong, but with that part of the door less than 90 degrees you can have the outer gap less than the inner gap; I can't.

And no, I can't really correct it. The area just above that is the door frame where the latch goes, so the fibreglass cannot be pulled in. It has to be molded at the proper angle and then mated up to the latch area.

I showed this in my build thread a while back:

923D2211-FFEE-466B-AE12-DC16089232DD_1_105_c.jpeg

Obviously my door is molded wrong for whatever reason.

Rick

[FFRWRX]

The first picture didn't show up. Here it is:

Screen Shot 2022-07-17 at 8.34.53 PM.jpg

[Ajzride]

That isn't going to be fun to fix. Maybe there is someone closer enough to you that you can pull a mold from a good door? Otherwise you are going to be stuck cutting and rebuilding yours.

[cob427sc]

It does look like the door is way out of wack. No chance of a replacement door from FFR? I guess worst case is to cut and reglass the rear door edge. I know it's a PIA but not entirely out of the possibilities. Sorry you have this problem. Keep us informed as how you fix it.

[FFRWRX]

This will be a bit long and will get into detail, but I'll lay it out for those interested. I'll explain what is wrong with the Factory 5 door design and how I fixed it.

Factory 5 uses the stock Subaru door hinges on the 818. The way they mount them puts the pivot point of the hinge about 1/2 way through the thickness of the door. Since the doors are thick, this is significant:

Screen Shot 2022-07-22 at 7.42.08 PM.jpg

When you do that, it affects how the gap changes at the rear of the door when it opens. I modelled it on the computer to show that it does what I thought it did, but here are some simple models to show it.

The stock F5 door geometry, showing the gap with the rear fender:

Screen Shot 2022-07-22 at 7.51.46 PM.jpg

As soon as the door starts to open, the gap reduces:

Screen Shot 2022-07-22 at 7.51.39 PM.jpg

So you have to have a large door gap when the door is closed, so it doesn’t rub when opening.

Now if the pivot point of the hinge is moved here:

Screen Shot 2022-07-22 at 7.51.32 PM.jpg

Now when the door opens, the gap opens too:

Screen Shot 2022-07-22 at 7.51.22 PM.jpg

So all is good. Factory 5 sort of gets around this (maybe) by angling the rear of the door so there is more gap where you don’t see it:

Screen Shot 2022-07-22 at 7.51.15 PM.jpg

I’m not 100% sure they actually do this. But those that don't have any issue with the door gap, I can't see any other explanation for it with the stock hinge geometry unless the rear of the door is angled like that. But it can’t be angled too much since the door skin bolts onto the door frame and the latch plate does not seem to be on an angle as far as I can see. BUT, if it is angled like that then the door would have to be moved forward a bit and that would mean a longer latch U-bolt part would be needed. Sound familiar to anyone?

Anyways, the issue with my doors is that the door skin was molded poorly and actually has the opposite angle to what I’m showing, so I have a larger gap at the outside than inside. So I can’t have a decent door gap without it rubbing when it opens. So moving the hinge pivot point seemed to be a solution.

I flipped the stock hinges around, made some brackets, and mounted them like this:

Screen Shot 2022-07-22 at 7.49.18 PM.jpg

That moved the hinge pivot to the inside of the door, but it also moved it too far forward. The gap situation at the rear was completely solved, but it caused the front of the door to swing in an arc that put it into the front fender. So a little more thought was required. I needed the hinge point near the inside surface of the door, but not so far forward. Couldn’t see how to do that with the stock hinges. So I thought ordinary door hinges might work. Sounds a bit Mickey Mouse at first. But I am hinging doors, so what better than door hinges? I thought it might look a little strange too.

So I found these hinges that I was pretty sure would work:

Screen Shot 2022-07-24 at 3.48.37 PM.jpg

Oh, wait, sorry, wrong picture. In order to use the factory holes and slots in the door and the car frame, the hinges had to have a leaf width of at least 3”, so the hinge had to be about 6” square; those are big hinges. I found these puppies:

Screen Shot 2022-07-22 at 7.50.06 PM.jpg

They are good for a number of reasons. First, I can use the stock mounting holes without more drilling the car parts and don’t have to make any new brackets. Second, these have no holes to start with, so I can drill what I want to line up with the holes/slots in the car. And last, these things are massive, 3/16" thick plates. Makes the Subaru ones look flimsy.

So with these in place it looks like this:

Screen Shot 2022-07-24 at 3.47.51 PM.jpg

I cut some of the hinge plates away that weren't doing anything in the way of support. They actually fit flush with the door and the frame mount, so will not really show at all when the rest of the panels are on. It does solve my issue with the rear gap and the swing at the front doesn’t interfere with the fender.

It actually wasn't a huge job to do this, skipping the intermediate step of swapping around the Subaru hinges. So if you are having trouble getting a decent door gap at the rear without rubbing, consider it.

Rick

[Scott Meyer]

Rick,

Does this help any with the door sag? We’ve got our car painted and quickly reassembled the doors so we could transport the 818S when we moved 1,000 miles south in April…and we are finally getting back to working on the car. I told Liam today as he was working on the wiring and lights…we have got to figure these damn doors out. The fit sucks, and the bottom is rubbing the side rocker panel, and binds on the rear.

[FFRWRX]

It depends where the "sag" is coming from. But you should be able to account for it when hanging the doors. Not quite as easy as it sounds though.

What I found was that if you prop the door in place with spacers around it and then tighten up the hinges, it won't work. The door will droop as soon as the spacer are removed. What you have to do is prop it up higher than you want it with the hinges loose. But of course you can't do that with the rear latch U bolt thing in place since that locates the door. So I removed that latch piece, propped it up much higher than I needed it, tightened up the hinge bolts, then removed the spacers. Then repeated that about 10 times with the driver's door; seriously. On the passenger side I got it the 2nd try. One problem is that if it just needs a little tweaking and you loosen the bolts, there is a good chance it is going to move where you didn't expect it; adjust the space at the bottom and the door may move forward.

So does my hinge mod help with door sag? I'd say probably not. My experience with a few kit cars now (and others I'm sure) is that when you adjust doors perfectly and take them off, they don't fit perfectly when you put them back, without a surprising amount of work again.

One thing that may help and I'm going to try and remember to do is something I saw referred to as "the Ferrari trick". May or may not have anything to do with Ferrari's though. I'm going to drill a 1/8" dia hole though the hinge and mounting bracket in the car (the frame side, not the door frame), one for each hinge once the doors are nicely aligned. Then remove the hinge from the car, leaving the hinge bolted to the door. When reinstalling the door insert a 1/8" dia pin (a drill bit will work) through each hole to help align the door when tightening it up. Should help, but I haven't tried it yet.

Kit cars are so much fun.

Rick

[Dave 53]

I recall spending about 3 days working on my doors. Several times, I was close to assuming the kit was flawed and I was ready to cut, drill and grind to "fix it". But I kept telling myself it was not the kit, it was me. In the end, the only modification I had to make was to cut a slit on the rear end, bottom of the door where it curves around and pulldoor slit.jpg them together just a little bit to keep from scrapping.

[FFRWRX]

But I kept telling myself it was not the kit, it was me.

Well, from my experience (and many others) with the door/fender/A-pillar fit, the roof on the 818C at the rear, and certainly the door windows, it is not me, it is the kit. I've asked in the "Ask A Factory Five Tech" area for them to comment on my findings here on the door hinges. Not that I expect them too, but until they show me otherwise, it is not me, it is the kit.