What size backspacer needed for pro stars 15x10

[Lturbo6]

Weld Pro-stars 15x10. MT 28x15 slicks. What size backspace do i need for 87 grand natiional? Problems is I got wheels from a buddy with backspacer already included with them. They were on an monte 86-87 g-body. When i pit them on my car i hear an stretching sound on both side. Airs up the air bags some to no avail. Is it something 'm doing wrong with the spacers correct way to install them. 3.75 or 4 spacers. Thanks alot!

 

[Grumpy]

Do a search.. I believe this has been beat to death a few times. Your rear 1/4 edge rolled ?? That 10" rim is HUGE !!

 

[pacecarta]

rolled lips? stock frame rails? axle centered on body
what tires as the section width will affect how much over the rims 10.5" size the tire bulge will be
and whats the backspace of 'your' 15x10 rims
all these will affect what total backspace you will need to run and depending on the rim what size spacer (if any) you would need

with tire and rim on ground face down lay a straight edge across the tire and measure to the back side of the rim , you want no more than 5.25" or youll be on the frame and depending on how loose your rear bushings are and how much the axle slides side to side you may need to run with even less backspace but every car is different ..do the math and add spacer and remeasure till your around 5" and then try it on 'your' car

once you're clear of the frame with a 10"rim and appropriate tire for the rim (295 or bigger) youll be into the wheel lips and most likely need to roll or raise the car up broncobilly style ,
and even if it looks good and safe sitting there how stiff the car suspension is and how much the axle twists which happens when turning off the road onto a driveway apron will also affect how much tire you can run because as the axle rises on one side it tilts taking away clearance at the lips , bags may help for the straights but on turning if you dont roll the edges you could end up cutting the tires . a stiffer swaybar helps the twisting but with stock even an aggressive turn can lean the car and cut the tires

 

[Grumpy]

broncobilly style

:biggrin:

 

[BIGONTS]

I don't believe they will fit without a frame notch. Mine is notched and I'm running 5" back spacing and a 325/50/15 = 28". Still close on inside and fender.

 

[GNBRETT]

5 was a perfect fit on my old car with a notch/mini tub tho. 325/50

 

[Lturbo6]

Would airing the air bags up some more help. Those who have pro stars what backspace are you using?

 

[tntdiablo]

15x10 4 1/2" back space

 

[toofastforyou]

15x10 4 1/2" back space

X2!...Yep!

also

"broncobilly style"

what??...I don't get it...:frown:

Claude.

 

[Lturbo6]

I'll try that, Where do I get the correct backspace from. anyone special, part number.

 

[ZNix]

15x10 4 1/2" back space

Sorry for the hi-jack, but I was looking at rims that are 9.5" Wide with a 5" BS. Is it fare to say that it would have about the same fitment as these rims? Considering the 1/2" is taken from width and added to BS..

Thanks
ZNix

 

[pacecarta]

BS is still BS regardless of the rim width
the 9.5 with 5bs will stick out less to the fender then a 10.0 rim with 5BS but when it comes to the frame you still have 5"BS + the tire bulge and unless youve notched the frame you'll need some spacers to get the frame clearance

 

[ZNix]

BS is still BS regardless of the rim width
the 9.5 with 5bs will stick out less to the fender then a 10.0 rim with 5BS but when it comes to the frame you still have 5"BS + the tire bulge and unless youve notched the frame you'll need some spacers to get the frame clearance

Okay, then again I don't mean to hi-jack. But what would you recommend for BS with a 9.5" Rim that will not go past the fender, and with no frame notch. The rim I want is a 17" so the tire bulge will not be very large. Most likely I will go low profile tires if I can. I think they are 275/40/17's.

 

[49-blues]

4.5" works!

 

[charlief1]

The rim I want is a 17" so the tire bulge will not be very large.

Trust me Zack, at your age the "bulge" won't matter for a few more years.:biggrin: Then it will be gone. LMAO! Sorry but I just hadda!:biggrin:

 

[chadswe4]

4.5" is the deal!!!

 

[49-blues]

I will be putting 295 x 45 x 17"s mts on the rear with a 4.5" bs and will just make it-I put a 8" x 17" rim with 4.5 bs and 255 x 45 x 17" a 10.2" wide tire and had a 1/2" space to the frame, if you measure across the mounted tire the tire to the mounting flange I had 5", from the axle mounting flAnge to the frame is 5.5", I'm putting 10" wide tires on 8" rims in the front and 11.5" wide tires on 9.5" rims in the back all with 4.5" backspacing.

 

[HUMBLE-U2]

x2 4.5 bs will work fine.

 

[Lturbo6]

4.5 bs rubbing all over the frame. I need 15x8

 

[ZNix]

Trust me Zack, at your age the "bulge" won't matter for a few more years.:biggrin: Then it will be gone. LMAO! Sorry but I just hadda!:biggrin:

Charlie your a hot ticket man . Made me laugh really hard with that!

Thanks everyone for the advice.