Project BBS Lightweight! From start to finish.

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BBS RZ lightweight 15x6.5 from a Mazda RX-7 convertible.  Lips polished. Centers painted.

BBS RZ 15x6.5 Lightweight

These wheels began their lives on a pretty hot car in its day. An 80's era Mazda RX-7 convertible.  They were stock wheels for that car.  Mazda had BBS make a pretty special wheel for the car. It was a a 15 inch wheel with a 6.5" width and was a one piece forged design.  

One cool thing about it was its weight.  11 pounds a wheel!  That's lighter than my 14" whyeels by far.  Usually bigger wheels means more weight which means slower braking, turning, and acceleration, but usually a nicer look.  In this case, we get all upsides and no downsides, except for maybe a a ride quality reduction because of the thinner sidewalls on the tires to maintain the correct rolling radius.  

There are 2 problems though with these wheels:

1. Bolt pattern.  The RX-7 uses a 5 hole bolt pattern (5x114.3), the 2002 uses a 4 hole bolt pattern (4x100) so the old bolt holes needed to be filled and the wheels redrilled to fit the BMW.  Not all wheels can be redialed because it needs a solid bolt bed.  These wheels just happen to be compatible with redrilling.  

2. Offset.  The offset of the wheels are ET40.  The desired offset for 6.5" wheels is ET30. Because they at 6.5" wheels I can probably get away with ET25 wheels and still fit within the wheel wells without rolling the fenders.  This will need to be done with 10-15mm spacers.  Cheap and easy, but I will need longer wheel studs to accommodate the spacers.  I already have longer studs in the front because of the big brake upgrade, so that just leaves the rears to be installed.  

Both of those problems are not difficult to overcome but I wanted to let people know they are not a simple bolt on.  

Why do that to these wheels instead of just getting BBS wheels that fit a 2002?

Cost and Performance and Uniqueness.  

The Process

The wheels I got for $200 used.  Not a huge market for them because not many people want stock RX-7 wheels.  They are forged 1 piece wheels and are very light.  Performance will be enhanced.  Wider tires, mean more traction and cornering grip.  Stiffer sidewalks will give me better cornering.  Less weight will make it accelerate, turn and stop faster.  Because I will have the lips polished and they are not made for  2002, they will truly be one of a kind in the car.  If I go to a car show, no one will have my wheels except me, making the car very unique.  

The first step was to have the wheels redrilled.  Pro Tire & Wheel in Norwalk did the work.  They filled the old holes and drilled new ones.  Simple.  Cost was $120.

Here are the BBS wheels after being redrilled from 5x114.3 to 4x100.

 

Then it was time to polish the lips.  Pro Tire & Wheel also did this and again for $120 I got the wheel lips polished to a shiny chrome like finish.  They are now like mirrors!  Amazing.  These wheels are unique in that they are correct widths for the 02 without flares or modifying the fenders and yet they have a lip and deep dish design.  This gives the wheel a very prominent lip and a deep dish look.  

BBS Polished lip
BBS RZ wheel with polished lip

Now that the lips have been polished and look amazing it's now time focus painting the centers and getting them ready for tires. So I was searching for a medium metallic grey. The one I used before I think was a tad dark so I wanted same thing lighter. I was off to O'Reillys auto to see what I could get. The lightest medium grey color I could find was a GM color Medium Metallic Grey. Here are some results of the first 2 wheels after a few coats of white primer and a few coats of Medium Metallic Gray and a few coats of clear. 

Wheels masked and primered in white high build primer.

 

BBS wheels after Metallic Grey Paint
Center Lug repainted in Duplicolor chrome paint.
BBS RZ, polished lip, painted center
Finished BBS wheel with blue BBS center caps.
BBS RZ, polished lip, painted center
Finished BBS wheel with blue BBS center caps.

The results are amazing! These wheels look like brand new BBS rims.

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