Offset / backspacing help please

[NYStepside]

This is my first post. I just recently found this forum and I’m very excited to have joined. The information here is tremendous. I have searched a little bit still have trouble figuring out the perfect backspace / offset. I have an 87 Chevy Stepside that has between a 3/5-4/6 drop. I approximate because the truck is being restored and not yet put together. I will be putting in a ride tech suspension system and along with my 2.5 inch drop spindles that’s what they estimate the final drop to be. I have narrowed my rim choice down to two. One is 9’ wide and the other has the option of 8.5, 10 and 10.5. I see many go with the 8.5 and 10. First question is will the 10.5 fit the rear? Also if I went with first rim would 9 fit the front? And lastly what’s the best backspace? I have read anywhere from 4.5-5 in the front and anwhere between about 5 and 6 in the rear. I appreciate the help and will be posting some progress pics in the coming weeks.

[NYStepside]

I forgot to add that the rim size will be 20”.

[Rapid Roy]

Welcome to the site

[NYStepside]

Come on I know there are a ton of smart guys on here. Someone has to know what will work

[NYStepside]

Waiting on some help before I purchase the rims. Anyone able to guide me in the right direction??

[NYStepside]

Alright let’s try this. Will the 9” wide front and rear work with 5 1/2 backspacing work all around?

[zieg85]

I doubt anyone will give you an answer.  It is going to be close and tire sizes are all over the map.  Sure don't want to rub new tires...  It's a trial and error

[NYStepside]

Is there a tire width front and back with 20’s and a backspace you are positive works?

[VileZambonie]

Buy a wheel fitment tool instead of guessing or borrow a buddy's set of wheels to try on or bust out the tape measure and roll the dice. There's way too many variables.

https://www.youtube.com/watch?v=ug3uLNL3aGc

[NYStepside]

I appreciate the response. Was hoping some would be able to share what has worked for them.

[VileZambonie]

The backspacing will be different for 9" vs 8.5" same goes for 10 or 10.5", what diameter wheels are you planning on running? You can fit a 12" wide wheel in the back if the offset is correct

Do yourself a favor and wait to buy wheels until you are done with your suspension work. Like I said, a lot of variables. We can all tell you what will work and then if it doesn't? I don't think you'll be very happy. You've got to take measurements. That tool is a worthy investment and you can resell it when you are done or just get the tape measure out and crunch some numbers once it's sitting the way you want it.

[NYStepside]

I am going to wait just wanted to narrow down to which rim. As I said earlier one would be 9” wide all around the other comes 8.5 up front and 10 wide in the back. I have read guys do the second of the two most commonly. Was asking if the 9 wide up front would work.

[VileZambonie]

It really depends on the backspacing and what diameter you are intending to run. I don't think you've told us that still.

[NYStepside]

I think that’s where I’m getting confused. Both come in a variety of offsets if that’s what you mean? I appreciate the hwlp

Wheel one:
https://www.carid.com/black-rhino-wheels/everest-silver-17486792.html?gclid=EAIaIQobChMIotq9nKWp2gIVE1mGCh0RvASTEAQYAyABEgJJMvD_BwE

Wheel two:
https://www.carid.com/tsw-wheels/bristol-silver-mirror-43164376.html

[NYStepside]

First rim comes with offset options of 15-20-25-30 for the 9” wide 20”

Second comes with the 8.5 wide offset options of 20-30-32-40
The 10” wide for the rear comes with options of 25-35-44-56