Pro Comp 16x8

[asrooster8100]

I am looking at purchasing the the Pro Comp series 69 16x8 5x5 -12 wheels and am wanting to to put 245/75r16 on them for my 2000 astro AWD LS. My main concern is whether or not the side door will just rub the tire or if this wheel and tire setup will completely keep me from opening the side door. Any help would be greatly appreciated.

[astrotardis]

I have the same wheels on my 03 . but 16x7 with 4" offset and 245 70 16 tires. And it just clears the slider by like 1/8 inch although I suspect my slider might be sagging a bit at full open. Im guessing with a stock offset you should be ok. I'm sure some others will chime in soon also!

[97cargocrawler]

Funny you should ask because this very same question came up last year in my Discrete Mathematics course. We in fact modeled a matrix to solve this problem with 95% certainty. In order to perform the necessary operations I need the following inputs:

Current leaf spring rate of your van:

Max and Min load for the rear 75% of the vessel:

Passenger side axle offset, aka "Dogleg factor":

Instantaneous atmospheric temperature and pressure at the time the door is accessed (try to estimate):

Gravitation force at that same location for the above input:

Your best estimate of the door track roller bearing wear (within 10% please):

Trim level of your van:

Roll degree:

Just a few matrix operations and I will have that answer for you in a jiff.

[zach914v8]

Funny you should ask because this very same question came up last year in my Discrete Mathematics course. We in fact modeled a matrix to solve this problem with 95% certainty. In order to perform the necessary operations I need the following inputs:

Current leaf spring rate of your van:

Max and Min load for the rear 75% of the vessel:

Passenger side axle offset, aka "Dogleg factor":

Instantaneous atmospheric temperature and pressure at the time the door is accessed (try to estimate):

Gravitation force at that same location for the above input:

Your best estimate of the door track roller bearing wear (within 10% please):

Trim level of your van:

Roll degree:

Just a few matrix operations and I will have that answer for you in a jiff.

[asrooster8100]

Wow. It really is as hard as I'm making it out to be.

[97cargocrawler]

Well no, the computer is going to do the math. I just need to know those static measurements. Imagine if you wanted to know while the van was moving! THAT would be hard! I think we would have to model the van like a gummy bear.

[asrooster8100]

LMAO

[MI_Ghost]

You have to be careful when comparing wheel specs. The 03-05 wheel specs do not directly relate to the 85-02 wheel specs. Wider axle width due to the brake upgrade increased the wheel offset.

85-02
15x6.5, +5 offset, 3.9" backspace
215/75-15

03-05
16x6.5 steel, +31 offset, 5" backspace
16x7 alloy, +31 offset, 5.25" backspace
215/70-16

16x8 5x5 -12 wheels and am wanting to to put 245/75r16
16x8, -12 offset, 4" backspace

245/75r16, Approx 30 mm (1.25") wider all to the outside.
Measure from the sidewall to the slider to see if you have the clearance for the extra 1.25" width.

[asrooster8100]

It looks like I should have plenty of clearance. With my stock setup I have over 2 inches of clearance to the side door.

[MI_Ghost]

With room to spare! On the rear at least!
And you will probably find that there is also 2" from sidewall to leaf spring.

Your Next point of concern will be the front end.
215/75-15 27.7" diameter
245/75-15 30.5" diameter
Your backspace is almost the same as stock but you will be 2.8" larger in diameter or 1.4" larger front and rear so there might be clearance issues on the front

[asrooster8100]

Thanks for the help. I have just installed the overland 4" lift and plan on trimming out the front fender. My main concern was my side door being able to open all the way. Thanks!

[zach914v8]

If you do end up havung issues, I think I have seen guys make some extensions on the slides before.... You could always lift it so high, that it doesn't matter.... Or make the door unto a gullwing, that would be cool, or better yet make it flip open from the top and put steps on it?

[asrooster8100]

Good to know. Thanks!

[97cargocrawler]

Thanks for the help. I have just installed the overland 4" lift and plan on trimming out the front fender. My main concern was my side door being able to open all the way. Thanks!

Say whaaaaaaaaaaat?! See that's info that would have been helpful YESTERDAY. Now I gotta restart the supercomputer.

...or better yet make it flip open from the top and put steps on it?

[zach914v8]

Thanks for the help. I have just installed the overland 4" lift and plan on trimming out the front fender. My main concern was my side door being able to open all the way. Thanks!

Say whaaaaaaaaaaat?! See that's info that would have been helpful YESTERDAY. Now I gotta restart the supercomputer.

...or better yet make it flip open from the top and put steps on it?

Sure, just make believe the spaceship is an astro...

astrosidedoor.jpg (10.83 KiB) Viewed 4018 times

[97cargocrawler]

astrosidedoor2.jpg (16.89 KiB) Viewed 3962 times

[MI_Ghost]

Thanks for the help. I have just installed the overland 4" lift and plan on trimming out the front fender. My main concern was my side door being able to open all the way. Thanks!

But did you take into account that your measuring point is 1.4" low and short of what you asked??

[asrooster8100]

Are you talking about the measurement to the side door?

[MI_Ghost]

Correct. The larger diameter wheel and tire combo will change the point where slider could contact the sidewall.

Stock: 215/75-15 27.7" diameter
New: 245/75-16 30.5" diameter

This difference of 2.8" increases the size both up/down and front/rear.
With the 4" lift already installed. The up/down change should be minimal.
This moves the point of contact with the sidewall 1.4" closer to the slider door opening where it moves outward before it moves back.

Make a cardboard L with the legs being 1.5" wide.
Hold it on the center of the wheel/tire with the front leg going across the tread.
Open and close the slider to make sure it clears the outer corner of the L.

[asrooster8100]

It's coming along. I have a little more trimming to do and some cosmetic pieces to get back on.