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MDC1969
07-26-2018, 02:43 PM
Hello everyone!

I'm new to the forum and this is my first post. I have a 69 Camaro that I've owned for 35 years now and I've decided to go the pro-mod route. I'm making good progress but is a labor of love and money!

The question I have is regarding backspacing for the front tires/wheels. I wish to run a 265/35 R18 tires on 9' wide wheels. I have 2" drop spindles and a Heidts front suspension. I've used some tools and it looks like a 5 to 5.5" back space will work. Has anyone run this particular setup that can offer any insight to this configuration?

Thanks!!
Mike
Tinker
07-26-2018, 05:21 PM
Welcome to the forum.

Do some searching within this forum. This has been covered many times. Its hard to say what exactly works because some spindle or brake packages change wheel offset. Aftermarket frame you have a whole new ballgame.
The old standard was 245's on 8 inch rim 4.75 backspace. Wheels have gotten wider. With each size increase, the difficulty increases much more. Pay close attention to the backspace with drop spindles, because the steering arm may interfere with the rim. Push the rim out, and tire rub occurs. Many members have spent a great deal of money and time trying to stuff bigger wheels up front.

Good luck!
MDC1969
07-27-2018, 06:20 AM
This form has been a great resource and has gotten me dialed-in pretty close. Since I know the width of my wheels, the offset will be a mathematical function of backspace and I do know the caliper clearance. I'm getting custom billet wheels so once they are cut I have to own the success, or pain! I did purchase a tool to measure backspace, (Wheelfit Pro 45, it actually mounts the real tire to the hub) it was expensive but seemed to be a good insurance against the cost of custom wheels.

Thanks for the tips, particularly about the control arm clearance with the drop spindles! I had not considered this before. Perhaps I can share this tool I purchased with someone else who is having to make these costly decisions.

https://www.cecodist.com/wp-content/uploads/2014/11/35-Chevy-Front-TMM-test-fit-straight.jpg