BrianG

Our local wheel guy does a fine job of straightening rims and the like, and he also says he can widen a wheel, too. I love the look of the Phone-dials (ya, I know I'm weird) but would like 9's and 10's built from my stock 7's. Any opinions on the process?

Chris Lockhart

In my younger days working at a tire store, we used to send steel wheels out for widening all the time. Don't see why it would be much different for the alloy wheels. I was thinking of doing the same thing with a pair of 15" phone dials, so I could run drag slicks on the back at the drag strip. The 15" slicks are pretty cheap, while 18" drag radials are pretty expensive. That's why I had intended to try this method. If you go for it, please post your results. <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

DaveW

This is new to me. What's the process?

DaveW

BrianG

Apparently it's "cut the rim"-"weld in a ring". I saw the operation. They use a lathe to cut the rim on a flat section then they have a fairly thick aluminum ring that they machine a 0.5inch "step" into on both edges, the new ID of which matches the OD of the cut "flat section". They press the 3 pieces together then true the wheel and weld them. It looks pretty substantial.
The problem, of course, is that the off-set shifts with the added width of the ring-insert. Luckily, for the 928, that's not much of a problem with this direction of shift.

slate blue

I would be very cautious with this process, most wheels for Porsches are forged and tempered, by welding them all of this is out the window. Are these wheels then annealed? If not they will have stresses that are caught in the metal, the way they come out is by a crack usually. All the best. <img src="graemlins/nono.gif" border="0" alt="[nono]" />

chris928

I would be very wary of this. As the previous post says, the forged rim is extremely strong. When you weld the aluminum it becomes very soft. It would need to be heat treated at least. There are issues when welding aluminum. Things like this may "work fine" at first but after years of use, imperfections in the weld can cause fatigue failure.

Also the phone dial wheels are a smaller diameter. There's nothing like the looks of a shark with 18" wheels...

slate blue

Guys has anything changed here? I was wondering if you got two wheels to make in to one. This way there is no ring. Example take a 57 mm offset 8" wide wheel and a 58 mm 10" wide wheel, cut the two rims down a common diameter area of the wheel. This way the best structural joint can be achieved and with these particular BBS wheels they are quite thick in that area.

Then put the rim in a lathe and tidy the weld inside and out, get the rim x-rayed and potentially re-heat treated. The rim would achieve a 82 mm offset with 10" rim width, which should be quite good for the front of the 928. The rears that are available in the same design are 51 mm offset and 11" wide. Again quite good I think. Thoughts, ideas?

WallyP

I wish that Fred Puhn still made his "Monocoque Wheels". These were custom-made three-piece wheels of spun aluminum. Any diameter, any width, any offset that you wanted, and probably the lightest wheels ever made. Mostly for racing back then (late '70s -early '60s). Fred sold the design and tooling, and the wheels were popular in drag racing up until 2002 or so.

"The original monocoque wheel was produced starting in 1965 by Chassis Engineering Company, originally of National City, CA and later Santee, CA. It was designed by Fred Puhn, a racing car designer (the Quasar, a SCCA D Sports racer) and author (How to Make Your Car Handle, 1981, and The Brake Handbook ,1985). Fred's partner at Chassis Engineering was Carter Penley Jr., a fiberglass and carbon fiber specialist, who later went on to form Penley Sports, one of the originators of carbon fiber golf club shafts.

The racing wheel portion of Chassis Engineering was acquired by David Boone in 1976 and renamed Monocoque Wheel Company. Although the original monocoque wheel had been designed for sports racers and formula cars, road racers had actually become a relatively small part of the company's market — drag racers early on discovered the light and strong wheels and became Monocoque Wheel's biggest customer base.

The production process for the wheel was pretty interesting:

1) Each half of the wheel was formed from 3/16" sheet T-6061 aluminum spun at relatively low speed on a huge lathe using rollers over a male mandrel consisting of multiple sections which could be added or taken away to produce wheel halves of different depths. A giant torch was used to soften and anneal the aluminum during the spinning process. This process took a lot of skill to avoid thinning the material in the outer bead areas, but properly done, the overall thickness of the aluminum could be maintained within a few thousands. It also took a lot of fortitude: working a 30" diameter spinning hunk of metal in front of a 2 foot flame in the 105F summers of Santee, CA was not for the faint of heart.

2) After spinning, the rim edge was rough trimmed and heat treated to a T6 level.

3) The raw wheel halves where anodized, or occasionally, powder coated.

4) The heat-treated and anodized wheel halves where machined on a precision lathe to true up all of the mating faces. This was a critical part of the process overlooked by some of the cheaper imitations.

5) An aluminum billet spacer was individually machined to match the dimensions of the two halves. Optionally, 1" or 1-1/2" lightening holes where drilled in the half faces between the center hub and the rim bolts.

6) The wheel was bolted together using aircraft grade hardware and the rim bead edges where trimmed true to the center mounting pad area.

7) The center joint crevice was sealed with silicone and an o-ring. "

I built one of Fred's Quasar D-Sports racers that later won the SCCA National Championship. Sharp designer and engineer.

hacker-pschorr

I have a set of custom wide phone dials, made by our local "Turbo Todd" many years ago. They were used as track wheels by three of the previous owners.

He started with eight wheels, cut them all in half and created a kind of tongue / groove channel on all the halves to be used. Then welded them together.

Have you checked available tire sizes? I no longer use them due to lack of 16" tires worth buying.

He has done this with a few different wheels without problems. The 16" manhole covers on his turbo car are 10+ inches wide. He has DOT drag radials on the back. For these wheels he cut them in half and added an aluminum ring.

slate blue

I am talking about the current 997 wheels which are 18" so tires are no problem.

hacker-pschorr

The original post / topic was talking about 16" phonies.

997 Carrera III wheels come in 11"

123quattro

It's not a big deal to do this. Just time and money. The Camaro I'm working on just had the rears widened from 9 to 10.5". It was about a month and $300/wheel I believe. They slice the wheel in half, machine a ring that matches the barrel diameter and then Mig weld it in.

Mike Simard

Welding forged Porsche wheels can make for a good wheel but nowadays there are one piece forgings that can be finished to your specs for less than 3k a set. That makes multi piece and welded wheels obsolete.

I'm looking into doing something like that in forged magnesium right now.

However, a 12" wide 16" phone' would be so cool as to trump all that! Too bad tires aren't available.

terry gt

I had a set of cast alum rims done 8-9 years ago added 2" to each rim 7.5 ----9.5 for the front ,9----11" for the rear 100% no problems . I use them for my track tires 275 / 40 front , 315 /35 rear . Greens automotive did them .

ender928

Can you post a pic of yours when you are available? I am interested in the result.