Which spacers to go with?

[84SFIGN]

My G body Cutlass has the 98-02' LS1 rear brake set up but the factory 15" rims require a .25" spacer to clear them. I've read that if I go with spacers, they should be billet and "hubcentric" meaning the spacer maintains the relationship between the hub and wheel which helps to secure the rim in mounting position. Can anyone recommend a good source? I see Summit has some but they look questionable.

Thanks

 

[jiho2]

Surprised you haven't had any response. But then, I don't have one either. I've been looking at this issue, but more to do with wheels, not yet to spacers.

I have confusion about what exactly the "hub" is. There seems to be a bevel running around the outside of the mounting surface that the studs are in. Mr. Gasket spacers appear to fit on this and have it for the wheel. Then there's the center bore. No wheels or spacers that I know of match the center bore, but everybody and his brother runs wheels with much larger center bores seemingly without issue.

Everything I've read so far seems to confuse these two things.

 

[SHADOWII]

Try www.ezaccessory.com They carry hub adapters as well as spacers.

 

[jiho2]

Surprised you haven't had any response. But then, I don't have one either. I've been looking at this issue, but more to do with wheels, not yet to spacers.

I have confusion about what exactly the "hub" is. There seems to be a bevel running around the outside of the mounting surface that the studs are in. Mr. Gasket spacers appear to fit on this and have it for the wheel. Then there's the center bore. No wheels or spacers that I know of match the center bore, but everybody and his brother runs wheels with much larger center bores seemingly without issue.

Everything I've read so far seems to confuse these two things.

Oops, I just noticed the part about LS1 brakes. Heh.

Just to clear up some of MY confusion at the expense of YOUR thread.... The stock setup on G-bodies isn't really hub-centric or lug-centric, but a little of both. The wheel center bores don't fit tight on the hubs, but fit close enough to help get the wheel flush and center the studs in the lug holes, which take beveled nuts that actually center the wheel. That's how people get by with lug-centric aftermarket wheels, which is just as well since that's all I've seen.

Sorry.

 

[T-CHRGD]

Many companies (like Baer Brakes) sell hub centric rings for aftermarket wheels. The come in many sizes. You would measure your hub and wheel center bore and pick one that fits. They are recommend, especially if you run the car hard. True, not many people use them.

 

[jiho2]

I looked for hub-centric rings. There's actually a company that specializes in those (I forget their name). Not even that company had any that would match aftermarket wheels to G-body hubs. You'd have to order a set specially made. And I've not found any anywhere else, either.

 

[jiho2]

And I forgot, it's not just mounting/centering, there's also the issue of loading. You hear that the hub is meant to take the loading, not the studs. The weight of the car, plus road shocks and insults.

And there's little or no information. Enough to drive you nuts, no pun.

 

[Boxcars]

For what it's worth, I run LS1 brakes with a 7/16" universal spacer with 2" studs. I've run this for years with no issues.

 

[jiho2]

I just found this old forum from 2006 where some actual engineers really get into the hub-centric versus lug-centric issue:

http://www.eng-tips.com/viewthread.cfm?qid=152939

They conclude that "hub-centric" is just to help get the studs centered, while the studs/lugs serve to CLAMP the wheel and hub into a single unit (the studs don't bear load), and the load is borne by the bearings. If the hub took any load at all, those plastic centering rings would get torn to shreds.

Again, sorry to take this thread off somewhere, but once I stumbled in, I had to thrash around....