what is your wheel backspacing when using Porterbuilt suspension

[G-NUT]

What is your wheel backspacing when using Porterbuilt suspension components? Narrowed rear axle?

Online & in magazines I see squarebody trucks with wheel backspacing that I like and don't like. I am installing a complete Porterbuilt extreme (level 3) suspension on my '85 GMC. I like the look of the Reyna Brothers Orange/White truck's wheel setup.

What I'm planning on running are 24x8.5 front / 24x12 rear Raceline wheels. There is the possibility that I'll run a 24x9 front / 24x12 rear U.S. Mags wheels. And also, depending on some things I may reluctantly run a 24x10 in the rear.

I'm curious to know what would be the best offsets for this and how much people have narrowed their rear axle for this.

[G-NUT]

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[G-NUT]

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[G-NUT]

bump, bump, bump

[andrewmp6]

Maybe ask in the suspension part of the forum.Or buy a wheelrite https://www.summitracing.com/parts/php-01201 and test out the size and back spacing to know for sure it works.

[G-NUT]

Originally Posted by andrewmp6

Maybe ask in the suspension part of the forum.Or buy a wheelrite https://www.summitracing.com/parts/php-01201 and test out the size and back spacing to know for sure it works.

Thanks for replying. I will post this question in the other forum. I've seen that device or one like it used before in magazines. Thanks for that. I think I'll try it too.

[lolife99]

Originally Posted by G-NUT

What is your wheel backspacing when using Porterbuilt suspension components? Narrowed rear axle?

Online & in magazines I see squarebody trucks with wheel backspacing that I like and don't like. I am installing a complete Porterbuilt extreme (level 3) suspension on my '85 GMC. I like the look of the Reyna Brothers Orange/White truck's wheel setup.

What I'm planning on running are 24x8.5 front / 24x12 rear Raceline wheels. There is the possibility that I'll run a 24x9 front / 24x12 rear U.S. Mags wheels. And also, depending on some things I may reluctantly run a 24x10 in the rear.

I'm curious to know what would be the best offsets for this and how much people have narrowed their rear axle for this.

I hate to say it but that's a really open ended question.
Too many varibles to compare to other people.

The front might get you a generic answer that works,... but:
1) which brand drop spindles?
2) stock length or narrowed a-arms?
3) how much do you want the wheels to tuck inside the fenders?
4) do you plan to drive it lay'd out?
These things all figure in to wheel backspacing.
And I have no idea if there is more width room on the 73-80 trucks vs the 81-87 trucks. (different fenders)

And then the rear:
1) inboard or outboard bags?
2) inboard or outboard 4-link (or is it a trailing arm suspension for 73-87)
3) narrowing the rearend: Most people buy the wheel and tire they want to run and place them under the truck with the bed bolted to the chassis (or mocked up) and then measure between the wheels. You also have to allow a little clearance inside and out side of the tire.
4) are you running a panhard bar or watts link?
A watts link with keep the rearend centered in the bed throught the suspension travel.
A panhard bar will shove the rearend slightly to the side that the bar attaches to the rear axle.

Just some things to think about when comparing numbers to "other peoples" trucks.

[G-NUT]

Thanks for responding. I know things can and will vary a bit from truck to truck, even if it's the same yr/body trucks looking to run the same thing. I'm just looking for an idea. Here's what I have going on.

front
1) McGaughys 2.5" drop spindle
2) PB 1" narrowed UCA's
3) I want the front wheels to tuck enough that I can drive with it lay'd out.

rear
1) inboard bags
2) inboard parallel 4-link
3) watts link

[andrewmp6]

I preach using a wheelrite so you know for 100% what will fit your setup or not.80 is cheaper then ended up having to buy another set of rims.