How to attach pizza pan smooth wheel covers to my PIP? (Prius)
 

The Plug in Prius standard wheels are 10 spoke cast alloy 15" with a snap in center cap. My driving is mostly on 55MPH hilly 2 lane roads with rather light traffic. I use the usual foam pipe insulation gill block and watch results on an Android tablet running Torque. After studying these forums I'll add some pizza pans to help improve fuel economy. Now the tough choice! How to attach the pizza pans? I see several options, which would you choose?

1. Single bolt centered in a center cap that is epoxied into the wheel + optional caulk around the perimeter of the pans.

2. Drill and tap 5 small (8/32) holes in the wheel spokes and use 5 pan head machine screws again with optional caulk.

In favor of 1 is the ability to restore to completely stock but against 1 is problems balancing wheels in the future. 2 Gives away the ability to economically restore to original stock condition and adds a negligible risk of structural compromise resulting in wheel failure. 2 Is more "work" to implement but probably results in a more reliable attachment. Which should I do?

Or, 3: find someone with a Prius, 2, 3, or 4 and trade wheels. Attach pans to stock wheelcovers and snap on. If I had bought a PiP, as was my original plan, that's what I would do. Barring that, I would be more inclined to explore option 1 than option 2: wheels remain stock with no alteration, less time to remove and replace pans.

Is this the wheel style in question?

http://blog.toyotaoforlando.com/wp-c...in-orlando.png

And here's a non-intrusive method that may work depending on how much clearance you have:

http://ecomodder.com/forum/attachmen...9&d=1414975137

http://ecomodder.com/forum/attachmen...1&d=1414975137

From: http://ecomodder.com/forum/showthrea...tml#post453097

This:

http://www.thetruthaboutcars.com/wp-...Hybrid-015.jpg

That attachment method might still work.

The PIP in the top picture is a 2010 demonstration model, the 2012 & later production models moved the charger inlet to the right rear. The wheels have 5 spokes in the picture mine have 10 but are a rather similar design with spokes that are not as flat on the outer face.

Am I understanding this concept correctly? A velcro "patch" is zip tied to the spokes, over each of these the mating velcro patch contains a screw that attaches to the pizza pan?

Vvman,
That is my car! Right color too!

It's not velcro, it's just a couple of pieces of corrugated plastic (coroplast) that serves to hold the screw.

You could use any material that can be drilled to screw into.

I think I'd actually recommend something sturdier than coroplast, though it's easy to work with.

Metro,
Thank you for the suggestion and answer. Because of the triangular shapes of the spokes zip-tying a block to them doesn't look to be reliable or actually feasible. So it really is back to the 2 options. I've ordered the pans and some center caps. I'm leaning toward option 2 as I plan on keeping this car for a good long while.

Well, I got the Pizza pans & my first obstacle appears! They are not quite deep enough!
So close lacking about 1/16". I'll try cutting some plywood to make a punch and die and attempt to make them a bit deeper.

Are you going to make a bump that's not off-center in the middle, or roll the edge to lift the whole face of the pan outward?

any progress on these?

I'm still waiting for the aftermarket center caps I ordered. I made the plywood punch and die and it works like a charm. To make them I made a compass out of my router with a block of wood and 2 pieces of 1/4" all thread rod, the compass center point is a 1/8" drill bit. The die is a piece of 3/4" plywood with a 15 1/2" diameter area routed to a depth of 5/16" (the 3/16" rolled edge of the pan sits on un-routed plywood). The punch is a 6" diameter piece of 3/4" plywood also made with the router-compass. After locating the center of the first pan I drilled a 1/8" hole in it and used the drill bit to align the punch, pan and die, set the die on flat concrete and gave the punch a few hammer blows. Presto it works!
I'm pretty well convinced that drilling and tapping 5 of the 10 spokes on a 6 1/2" radius circle with 6-32 screws located in the middle of the spokes will not compromise the wheels and give a really secure mounting. I'll still use a bolt through the center cap but it is essentially cosmetic but useful to speed re- installation. Now has anyone got an easy way of getting 5 equally spaced holes on a 6 1/2" diameter circle?
I plan on using rubber washers between the pan and spoke at each screw and using silicone RTV on the screws as a low torque thread locker and may add a very thin bead of silicone RTV around the perimeter of the pans.

6.5 X pi = 20.4203522483336. Mark the circle using 4" arcs, once clockwise and once anticlockwise. Then with any discrepancy, split the difference.