Something new is coming
Been a long time and I’m way behind on posting any activity. Life, job, those types of things have gotten in the way of racing and playing with the Camaro, but behind the scenes some things are in progress on my ’67 Mustang that I wanted to share.
In college, I got my autocrossing start in the ’67. It was a pretty entertaining ride and for years the suspension setup didn’t change until last winter when I upgraded to the Mike Maier Inc. rear panhard bar, shocks, and rear sway bar. Since last fall, I’ve driven the car a fair bit, upgraded the front brakes to a Wilwood 12.88″ rotor with 6 piston caliper (note, these are for a 1970 spindle, not a normal ’67!), and also tried out a stiffer set of front springs.
Big step up from the old Kelsey Hayes 4 piston calipers.
And for the record… 12.88″ rotors and 6 piston Superlite calipers fit perfectly inside a 16″x8″ Vintage Wheelworks V45 with 4.5″ of backspacing!
I drove the car a fair bit over the summer like this, but I got the itch for something better. The front suspension, though only having ~25,000 miles on it was showing its age from years of abuse at college, not to mention I’ve learned a whole lot about what is “good” when it comes to suspension since my Dad and I put the car together. So, out came the dreaming and in came the parts!
A MOD1 front suspension package (minus the sway bar) arrived from Mike Maier Inc. While I could have built something myself, time and a proven combo won out over DIY. Mike knows his stuff and getting a set of shocks that were already setup for this chassis was a huge benefit as well. I went with a set of single adjustables instead of doubles, sometimes you got to hold yourself back just a little bit…
Then it was time to go to the next level of silliness. Big wheels and tires are what every autocrosser wants and muscle car guys can never seem to get enough rubber under a car. I had dreams of 315s on all 4 corners of the car and hatched a plan to make it happen. Using a wheel spacing tool, I was able to visualize what might rub.
On a vintage car like my Mustang, wheel choice is difficult. Modern cars have LOTS of backspacing (or large positive offset) which means the hub to wheel mounting flange is very far outboard on the car. There are lots of benefits to this. If you recall back to the Camaro front suspension design, we ended up with 9″ of backspacing in the front! Modern cars typically are upwards of 6″ of backspacing on a 8″ wheel. This is a big change from the 4.5″ that a classic Mustang usually runs. When a modern wheel gets fitted to an old car, the wheels sit too far inboard and end up hitting body, suspension, you name it, not to mention they end up looking funny.
For the Mustang, I needed something on the order of 4.5″-4.75″ in the rear to avoid hitting the leaf spring or the inner wheel tub. Why not tub it you ask? Couple of reasons – 1) the contact point is only the front of the wheel tub (see the white splotch in the picture above), the rest of the tub has a lot more clearance. 2) putting in tubs screws with the interior panels and I didn’t want to modify them. 3) I wanted a wider body look to the car, because flares are cool.
Now I don’t plan to go as nuts as the Hoonicorn… but 315s are a big step up from 225/245 combo that I had on the car!
Front options in the wheels are limited to 5″ of backspacing with a factory spindle because the upper ball joint gets in the way, even with 18″ wheels. My budget isn’t unlimited and I wasn’t chasing grams. This ruled out the majority of custom wheel options (silly money) and a good quality cast wheel should hold up just fine. So I started looking into wheel spacers. Search the internet and you’ll find horror stories galore on wheel spacer failure. The engineer in me knew that spacers would be just fine, as long as they were executed correctly. I won’t go into all the details, but it boils down the following: quality materials, proper design (hub centric if possible), and proper installation/maintenance. I couldn’t get to a hub-centric design in the front, but the factory wheels aren’t so I think this will work.
Long story short and tons of measurements later, I’d settled on wheels, spacers, and tires! After looking at a lot of different style options, I picked one which was a more updated look than the typical Torq-Thurst style wheel you always see.
Cosmis Racing’s XT-006R ended up taking the prize. While I’m not enamored with the lettering, these wheels had the spoke shape I was looking for, a decent amount of wheel lip, and came in an 18×11 with a +8 (6.3″ backspace) which meant I should be able to get away with a 1.5″ wheel spacer. I ended up with this style of spacer as they’re the safest to run. Putting on this big of a spacer that’s a slip-on over extended wheel studs is a big no-no.
A little photoshop work sealed the deal!
I’m super pleased with the quality of the powercoating on the wheels and all the machine work on the hub face looks to be very good. Pricing was also in the ball park, on the order for $300/wheel which is pretty fair considering the size of the wheel.
Tire choice was the BFGoodrich g-Force Rival S in 315/30/18. Hot street tires in autocross seem to be the flavor of the month, but the BFGs had a “reasonable” price and I’m not planning to compete a whole bunch anyways so these will fill the bill. Rear look to fit very nicely with the expected fender flare work needed of course.
Inside looks to have enough clearance. This is with the axle sitting on jack stands, so the suspension is loaded a fair bit. If the front wheel tub rubs, there’s always some persuasion that can happen with the proper application of a sledgehammer. Special note, the rear axle in my car is out of a Lincoln Versailles which is ~2″ narrower flange to flange than factory (more on that in a minute).
Front fitment is where it gets a little interesting. I knew mods would be needed to the fender where, but I think I might have bit off a little more than anticipated.
Well those flares won’t work… Anyone need a set of Maier Racing bolt-on flares?
Not the end of the world. I’d had a gut feeling when I ordered the wheels and tires, deciding “screw it, I’m going big” I’d run into something like this, but that’s part of the fun right?
Picture from the underside of the front showing off why can’t have anymore backspacing. Could maybe squeeze in another 1/4″, but that’d be it.
That’s it for now. I’ll be getting the car back on the road with the old 16″ wheels and tires first to get some driving impressions of the new Maier front end before I dive into the flare project. More fun to come soon!
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Would the same wheels in 18×9.5 with +10 offset fit front with no problems?
Have 68 coupe that I’m doing same Mike Maier suspension and wilwood brakes on.
Hopefully you might be able to help.
Thanks
JUSTIN BENEFIEL
Hey Justin, best you can fit is 4.75″ backspacing in the front unless you change the spindles. So with a 9.5″ you’ll either need to run spacer/adapters like me or look at different wheels.