wheelworks weelfit 45 accuracy

[DCx]

I decided to up and buy a wheelworks wheelfit 45 from summit racing for the tune of $350, only because I have a 67 mustang coupe with a fox body 8.8 axle with ebay sn95 rear disc brake brackets. It should make for some fun rim spacing..

I picked up some brand new bridgestone potenza pole position tires in 275/35/18 and plan on running a 18x9.5 rim. These are some massive 275 tires. They look a lot wider than the 275/35/18 BFG drag radials on my 69 camaro that are mounted on 18x9.5s.



I messed around with the tool today and placed it into the tire. I sure had a hell of a time getting the bead clamp on. These tires have a huge protrusion for rim protection and the clamp didn't set to well on it. i eventually got it assembled.



Instructions say to set the slider to one inch wider than rim width so i set it at 10.5. Backspace settings call for .5 inches wider on the ruler to account for the mounting plate thickness so i set it at 6.5 for 6" backspace. well here are the results...



The wheel tucks pretty well but it's very close to the leaf spring. I placed this same setup on my dads 67 fastback with a factory 9" rear with drums and he had a safer distance to the leaf spring but still too close for comfort.



So how accurate is this thing? i feel like its not to accurate for the actual rim size. Testing a 5.75 backspace seems to be the sweet spot but I haven't lifted the axle up yet to get an idea of ride height since the car is on the lift and I'm still using the factory sky high leaf springs. I'm sure a 5.5 backspace would be safe but the wheels might stick out some and I would need to have the fender float over the tire. I'm starting to see that not too many companies offer 18x9.5 wheels with a preset 5.75 backspace.... 5.5 and 5.25 seem the most popular.