Wheel Spacers Still Confused!!

[gopats76]

I have just switched from 315 Nittos to 315 BFG Drag radials and am having some rub issues when the car is in the air on a lift etc. I do have the replica 17 x 10.5 in. wheels and I also have polyurethane differential & subframe bushings, IRS subframe bracket kit, IRS differential cover brace etc. The car is lowered with Eibachs but the rear does not sit as low as my GT did. I can supply pics if needed of the cars stance. The car drove fine with no issues back form the tire shop but I still don't have a warm and fuzzy. :??:

After researching I am still confused as to what brand and size wheel spacer I actually need. Any info would help at this point. Thanks in advance!

 

[Top_Fuel]

...just switched from 315 Nittos to 315 BFG Drag radials and am having some rub issues when the car is in the air...

What you have discovered is pretty typical. Those BFGs are too wide to fit on most Cobras without some rubbing when the rear suspension is totally unloaded.

The sidewalls are probably rubbing the bolt heads pictured below, right?

If that's the case, you have 3 options:

1. You can use wheel spacers for more clearance
2. You can modify the IRS bolt heads to shorten them
3. You can swap out the bolts with new ones with shorter heads

If you need wheel spacers, get the 3/8" hubcentric spacers from LFP:

http://lightningforceperformance.com/index.php?main_page=product_info&products_id=514


If you want to modify the bolt heads, here's an example:

If you want to replace the bolts, you can try these:

http://www.maximummotorsports.com/s...roduct_info&manufacturers_id=&products_id=495

 

[gopats76]

Thanks for the info. I'll give that a try with modifying the bolts today...

 

[firemedic]

The LFP spacers are nicely done. Even with the low profile 14mm bolt, or shaved bolt, I would still put on the LFP spacers. They help get the wheel that much further out the well and look 110% better.

 

[gopats76]

Some dude told me that wheel spacers weaken the studs. Any amplifying info on that?

 

[Top_Fuel]

Some dude told me that wheel spacers weaken the studs.

There is some truth to that. That's why you want to stick with hubcentric spacers. Read this...

What is the difference between hubcentric and lugcentric spacers?

Hubcentric spacers have a recess that fits onto the hub as well as a protrusion that fits into the back of the wheel. When installed, a hubcentric spacer meshes with a section of the wheel and a section of the hub at the same time. The hub, spacer and wheel become mechanically joined together through the clamping force of the lugnuts.

Lugcentric spacers are completely flat. When installed, they only serve as a spacer and do not allow the hub and wheel to remain mechanically linked.


Which is better: hubcentric or lugcentric spacers?

Hubcentric spacers are strongly preferred. Because they become directly linked with both the wheel and hub, hubcentric spacers have two distinct advantages:

1. The wheel will always be perfectly centered on the hub when the spacer is installed.
2. The load on the wheel is transferred through the spacer directly to the wheel hub. This is because the spacer is supporting the wheel while the hub supports the spacer.

Lugcentric spacers, on the other hand, rely on the studs to center and support the wheel. The wheel load is then transferred through the wheel studs instead of the hub. This can cause stresses on the OEM studs for which they were not designed. The result may be accelerated fatigue or tension overload of the wheel studs. When over-stressed, wheel studs WILL eventually break.

 

[gopats76]

Will I need to replace the wheel studs with hubcentric spacers?

 

[Top_Fuel]

Will I need to replace the wheel studs with hubcentric spacers?

As long as your lugnuts have adequate thread engagement with the stock wheel studs, you should be fine.

Quoting Maximum Motorsports' website:

The factory wheel studs are long enough to allow the use of 1/8" and 1/4" thick wheel spacers with most wheels. You must check the amount of thread engagement on your car to ensure that at least 6 threads are fully engaged after installing the wheel spacer.

Plenty of people are running 3/8" hubcentric spacers with stock wheel studs. To do this safely, you must use EXTENDED THREAD lugnuts. These will get you some extra thread engagement. Here's an "ET" lugnut compared to a standard lugnut...

When you buy spacers from LFP, they include these special lug nuts. Be sure to torque them properly and re-check them after a short test drive.

 

[gopats76]

Cool thanks again!

 

[dirtywhiteboy]

wow, great info guys!
one more question...LFP, do they not sell anything for cobras other than '03-'04?

 

[SonicBlueFTW]

being lowered i did not need spacers. the bolt is on the inside of the rim