The "Bring it Back" 71 Super Vert Thread

[mountainkowboy]

Thanks Marc...........let go another direction.

So if I have the drums re-drilled to 4x100 (do they make a replacement in that pattern), I could go with a FWD style offset and correct the scrub, but will have to have small OD springs in the front, or I will have rub issues?

[Marc]

That'd be one approach. Aftermarket 4x100 drums are readily available for Standard front, but I've never seen any for Supers so it'd be a re-drill proposition. Or, you could do a disk conversion (there are 4x100 "Karmann-Ghia" rotors made). Many FWD rims don't have a center hole that's big enough to go over the rim of the ACVW front wheel bearing dustcap, but it can be ground off...just makes it a hair harder to remove at service time.
If there are Porsche rims that you like, there's a good chance of finding them in 6 or 7" with a lot of offset - even many RWD Porsche rims have more backspace than VW - so if you're going to go with redrilled drums/rotors you might want to go with 5x130 instead, provided you can find some 6x15" rims with enough offset (or step up to 16 or 17").

Here are just a few of the off-the-shelf rotors/drums available from one store, there are others too:
http://www2.cip1.com/ProductDetails.asp ... 23-501-100
http://www2.cip1.com/ProductDetails.asp ... C-C10-6742
http://www2.cip1.com/ProductDetails.asp ... 7-075-113N
http://www2.cip1.com/ProductDetails.asp ... 23-501-301
http://www2.cip1.com/ProductDetails.asp ... C-C10-6750
http://www2.cip1.com/ProductDetails.asp ... 23-501-310

Many Porsches use bolt-on and/or pass-through spacers; various thicknesses are available to allow dialing in the effective backspace. I have the bolt-on ones all around on my Bug (yes, I have 40 lugnuts) with 16 or 17" Boxster rims. One thing I like about them is that the spacer stays put on the redrilled-pattern studs in my front rotors so they aren't being "tested" every time I change tires.

The blue car has CCC fiberglass wider-than-stock fenders; similar wheels on the black one with stock fenders, just took thinner spacers. Both these cars have 924T/944 Porsche rear brakes which widen the track compared to Beetle drums. Wheels are Boxster.
http://img.photobucket.com/albums/v212/ ... FF9D9F.jpg
http://img.photobucket.com/albums/v212/ ... B9BD5D.jpg
http://img.photobucket.com/albums/v212/ ... G_1125.jpg
http://img.photobucket.com/albums/v212/ ... G_0049.jpg

[mountainkowboy]

For now the suspension fix/repairs will be put to the side. Yesterday I started the repair of the top hinge mounts, at some time someone attempted to repair them. Talking with Chuck at Chucks Convertibles, he said that during those years the mount area was weak and if the top wasn't lubricated, it was pretty easy to tear the mounting out.

This is the before, I will add pics as I progress through the repair.

[Buggin_74]

Thanks Marc...........let go another direction.

So if I have the drums re-drilled to 4x100 (do they make a replacement in that pattern), I could go with a FWD style offset and correct the scrub, but will have to have small OD springs in the front, or I will have rub issues?

Anything in 4x100 is going to need narrow coil springs at its a pattern not really made with offsets more than et35.
you wont find any that clear stock springs.

But once you go 4x100 and narrow coil your rim choice is almost endless as its one of the most common 4 stud patterns.
Nissan, Honda, Toyota, Mazda, Ford, watercooled VW, early BMW etc all ran 4x100 so easy to pick up and a safe pattern to redrill in stock brakes.

Just to give you an idea these are all et40-et45rims and fit perfect

[Marc]

...Anything in 4x100 is going to need narrow coil springs at its a pattern not really made with offsets more than et35.
you wont find any that clear stock springs...

4x100 rims with less backspace than typically found on a FWD car are out there, but they are the exception. And the whole point of the exercise is to move the tire contact patch inboard to reduce the scrub radius, so if you're going to the trouble to change bolt patterns you may as well plan on some smaller-O.D. coil springs.

An offset "more than et35" would have even more backspace, exacerbating the scrub radius problem..."ET" comes from the German einpresstiefe, meaning insertion depth and is a measurement of the displacement of the lugbolt plane from the centerline of the rim. Any positive ET number indicates that the lugbolt plane is closer to the outside of the rim than to the inside (more backspace than frontspace), and almost all stock wheels for any make of car are positive offset. A rim with a negative ET would be like the "reverse" rims of the `50s and `60s where the center of the rim was cut out and turned around to give less backspace/more frontspace in order to widen the trackwidth.

ET numbers are expressed in millimeters by convention, while backspace is given in inches. Backspace also is measured from the lugbolt plane to the outside of the lip of the rim, which is typically ~½" more than to the area where the tire bead sits (the latter is how rim widths are measured).

Take the case of the stock 4" ET40 rim for example. Its center is half of 4", plus about ½", from the outside of the lip "in" from the dirty side of the rim. The 40mm positive offset tells us how much further in the lugbolt plane is.

1" = 25.4mm so 40mm = Approx 1.57"

Add them up to get the backspace measurement. 2 + ½ + 1.57 = just over 4".

A stock Type III/Karmann-Ghia 4½" ET46 rim will just barely fit on a 1302 with stock springs if the tire is skinny enough. Its backspace is ~4.5". The 5½" ET34 Sports Rim is ~4.6", and it won't fit - obviously neither would the 914/4 5½" ET40.

A stock May`72-up Type I 4½" ET41 rim will fit (backspace of ~4.3"); the early ET26 Sports rim was designed for the 1302, so it fits too. Backspace is ~4.25". With either of these rims you get about ¼" or so of clearance between the inner sidewall and the coil spring, depending upon the tire.

Say that you got some 6½x15" ET33 BBS 4x100 rims like these: http://i1051.photobucket.com/albums/s42 ... M00046.jpg

Their backspace would be just over 5" (3.25" + 33mm + ½") so they obviously won't work with the stock springs unless you added some spacers about 5/8" thick - and that would defeat the purpose of going to all this trouble. But if you fit coil springs which were 1½" smaller in O.D. you'd gain 3/4" of sidewall clearance, enough to work. The inside sidewall would be ~1" further inboard than stock, while the outer sidewall would be 1½" further outboard, so the scrub radius would be greater than stock but only by about ¼".

The smaller the O.D. of the spring, the larger an ET number you could run to tuck the tires in even further and reduce the scrub radius.

Ideally you want at least ¼" of sidewall clearance on the "light" (front) end of the car and at least ½" at the rear. More would be better, but most of the time that'll be enough for you to realize that a tire is going down and get to the side of the road before the sidewall gets damaged as the tire bulges from underinflation.

One last pitch for the Porsche 5x130 pattern - 6x15" "Cookie Cutters" or Fuchs would look bitchin' on that `71 IMO (the latter would be more period-correct, but either would look better to me than some ricer wheel with 8 holes in it). Say you got some in common ET35 or 36, the backspace is ~4.9" and the scrub radius would actually be a little better than stock. There's a wide variety of Porsche wheel styles from which to choose if you ever go to a larger tire, and most are around ET50 or so which means all it takes to use them is the appropriate width spacer.

[Buggin_74]

Sorry that was just my bad explaining.
2 decades of buying, selling and fitting rims I'm well versed in how offset works, but good explanation.

What I was trying to say is if you didnt fit narrow coil springs the only 4x100 wheel that would clear would need et35 offset or further out (less offset) to clear, then they would start interfering with the fender.

I've just managed to sneak some 15x6 4x100 rims under with stock springs, they were from memory et35 with 6mm spacers.

[Marc]

I realized it was just a brain fart, I wasn't presuming to lecture you - just trying to lay out the basics for the O.P. so he could figure this stuff out on his own.

...I've just managed to sneak some 15x6 4x100 rims under with stock springs, they were from memory et35 with 6mm spacers.

Was that on an early or late Super?

[Buggin_74]

All good, I probably confused people more than I helped.
Anyway another option that I don't know if its been mentioned is the tapered hour glass springs that topline sell.

They buy you a bit of extra space without the expense of going Maxx struts.
I've not had any experience with them though so I can't vouch for how much they give or what the ride's like.

Its a mix, its a 74 super that was the later 2 bolt but swapped to earlier 3 bolt so you can call it early.

[Marc]

...They buy you a bit of extra space without the expense of going Maxx struts.
I've not had any experience with them though so I can't vouch for how much they give or what the ride's like.

Me either. They call them "Sports Springs" and they look like they'd be small enough in outside diameter to gain about an inch of backspace room, but I can't say for sure either.

Its a mix, its a 74 super that was the later 2 bolt but swapped to earlier 3 bolt so you can call it early.

Sounds right. I think you can get a little more under stock fenders w/stock springs on a 1303, 6½" should go or maybe even 7" if you get everything just right...but as I mentioned above, it's smart to leave a little room for sidewall bulge so you don't end up destroying a tire over what should've been a minor puncture.

[mountainkowboy]

No worries Buggin_74 or Marc, I understood the "wheel speak", I used to co-own an auto accessory shop back in the day. Lifting, lowering, custom builds, alarms, that kinda stuff. Mostly American stuff, but we were building a lot of Baja's, bugs and ghias, then too. They were painted Kawasaki green, Ford electric blue and the like. We called it "Team Skittles" due to the colors....LOL. That netted us a nasty letter from Mars Corp with the threat of legal action for using the name without permission. Those were the days though..........

[mountainkowboy]

So it took most of the day with the small array of fab tools that I now have. But the repair panels are now fitted and prepped for weld in. I think that I will add a stiffener plate behind the factory steel on the top part just to make it stronger in the long run.

[Marc]

...I think that I will add a stiffener plate behind the factory steel on the top part just to make it stronger in the long run...

We never saw many convertibles in my Seattle shop so this is new territory for me, but if the problem is as common as Chuck makes it sound you're smart to make it stronger than stock if you can. Lookin' good so far!

[mountainkowboy]

Got the repair panels done with the added "stiffener" made from 12 gauge strap that I had around. Notice the rosette holes on the left side, (looking at the back of the panel) there is internal structure that the original was spot welded to. Was going to do a captured nut then I noticed that the factory plates didn't have really any movement to them. Got the right side all burned in today and started dressing it for final skim coat and primer.

[SCOTTRODS]

I would have wanted "floating Nut plates" in there.... but that looks pretty darned good. Nice work.

[mountainkowboy]

The top is back on............WOOOOOOHOOOO. There are a few problems with the frame that I have to fix. The hinge pins at the front and rear window joint are completely worn out and REALLY sloppy. Need to call Chucks Verts and see if they sell a pin/bushing kit, and I pretty much need all new wood, but will replace it as funds permit, the over the rear window bow is on its way......it was completely missing. the passenger side is having a bad misalignment problem that I need to figure out, but I'm done for today. I tore the wasted headliner out and I will see if I can re-sew some of the seams that are coming apart on the canvas top so it will make it through the winter.