Hi, i'm doing a Grand-am brake conversion on my '87 GT and the only problem is the center ring (on front wheels) does not come out as far. As a result, the wheel will be centered by the lug nuts. Is it safe or can i have problems with that ?

Thanks.

IMHO, I woudn't do it; the hub and wheel rim together support the weight and loads of the car as a system, the wheel lugs can stand the slight increase in tension okay (as from cornering loads) but I wouldn't trust them for sheer stress as you'd get by static weight plus road bumps.

pretty much all the brake upgrades cause this on the fronts

if you aren't comfortable with it then you can have a steel centering ring made and welded onto the existing protruding ring

The main problem I see is that the lugnuts won't do a proper job of centering the wheel on the hub, there are just too many tolerances acting against centering that way. Results will likely be the same as an out of round wheel or tire.

JazzMan

Aren't most of the after market wheels that folks use only centered via the lug nuts?

It will work fine. The lug nuts have always done all of the work. A lot of people (including myself) are running Grand Am brakes, as well as a variety of other swaps. There have been no problems.

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1986 SE 350 V8

Properly designed, the lugnuts only hold the wheel to the hub and they are centered on the hub offset. That said, as someone else pointed out, most aftermarket wheels require centering rings and they are made of plastic, for the most part, so the wheels are actually held in center by the lug nuts themselves and not the centering rings. If you do have wheels or hubs that center this way, torque your wheels then drive them a few blocks, then torque them again to make sure you didn't have anything stuck behind them or that they were tightened off center somehow.

John Stricker

quote Originally posted by tesmith66: It will work fine. The lug nuts have always done all of the work. A lot of people (including myself) are running Grand Am brakes, as well as a variety of other swaps. There have been no problems.

quote Originally posted by Phil: Aren't most of the after market wheels that folks use only centered via the lug nuts?

No. Aftermarket wheels with the larger holes are supposed to be used in conjunction with a centering ring. If you are running aftermarket wheels like that without the rings, get them.

Lugs nuts on most vehicles including Fieros have a "conical seat" they center the wheel as they are tightened. The Fiero rims arent truly centered by the hub, the lugs center them as they tighten down, which is one of the reasons you are supposed to tighten them in sequence. I wouldnt worry about it, I dont have centric rings on my 12" rotors or rims on my 88GT and I run the crap out of it, corner as hard as the thing will go, stand it on its nose daily, and bust out the occasional doughnut fest without inncident. Until recently It was dead smooth vibration wise to 150MPH, now Ive got some kinda vibration, but im confident it has nothing to do with this.

Lug Centric Wheels are not a problem in/of themselves. Many aftermarket wheels are installed this way. (A number of the wheel makers say doing this is just fine as long as you follow a rule or two.)

How you tighten them is very important.

Hub Centric wheels aren't always perfectly centered by the hub but they also resist being clamped more than a very tiny fraction off center. (OE Steel wheels frequently are "fully" hub located in that they are as tight on the hub as the car makers felt they could get them short of pressing them on the axle.)

Lug Centric wheels can be tightened allot more off center than many would think even with cone lugs. (Without cone lugs is worse.)

With lug centric you want to work all the lugs down firm by hand in at least a couple stages. AND NO load on the wheel!!!!
Then carefully torque them with a decent Torque Wrench and avoid significant loading on the wheel if you can.

I have lug cetric after market wheels and I can tell you that if you tighten the lugs with allot of weight on the wheel you can get them off center enough to shake your teeth loose even on a completely OE Fiero with its cone lugs.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurasic Park)

The Ogre's Fiero Cave (It's also at the top of every forum page...)

[This message has been edited by theogre (edited 02-15-2006).]

quote Originally posted by theogre: . (OE Steel wheels frequently are "fully" hub located in that they are as tight on the hub as the car makers felt they could get them short of pressing them on the axle.) \

Yea, no crap. We've had ford trucks come through the shop that took a 20lb sledge hammer to knock the rims loose, and not tap tap tap, sometime you have to WAIL on it to get em off. Those tight clearances can be made into makeshift welds with a year's rust. Good luck getting them off without bending the rims, some of them are on too tight to come loose just hitting the rubber of the tire.

quote Originally posted by 86GT3.4DOHC: We've had ford trucks come through the shop that took a 20lb sledge hammer to knock the rims loose....

Been there, done that. Not just on Ford either. Common with allot of cars in the rust belt. Al hub centric wheels can actually be worse. Aluminum expands like mad as it corrodes and Al oxide is unfazed by penetrating oils.

One of my sets of wheels is lug centered.

To tighten, just use a 3/8" ratchet to snug the lugs while pounding on the sidewall of the tire with your palm (no weight on the wheel). The pounding helps the wheel center on the lugs as they are tightened. Once all are snug, then tighten them fully. Never had a vibration issue with this method.

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Thanks everybody, also, i'd like to know if somebody are using the GA brakes set-up and how do you like it ?

I am useing the GA brakes in the front, stock rear. I have to much front braking right now. I need the hand brake, so I didnt do GA rears. I expect with GA rears, braking would be ALOT better than what I got now.

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1985 Fiero SE - Plain Red V6 Coupe
3.1 Crane272 MSD 4.10-4spd DarthChip Borla
D.A.M.M. - Drunks Against Mad Mothers

The wheels are held in place by the nuts. That's why the nuts or bolts always are cone shaped. The cones is what centers the wheels.
The center ring is there to help keep the wheel in place while you get the nut's/bolt's in place.

Wery important that you don't over tighten the nut's/bolt's. When tightend to much, they are stretched, and stretched enough they break.
They don't usualy break driving to work, they break when you puch the car, the litle extra. Hence when you least want a wheel to come of.
I don't remember the exact torque for tightening wheel, but i belive it's around 20 N/m (Newton/meter).
The number varies with the size of the nut/bolt. Bigger nuts/bolts may need a higher torque.
Tighten the wheels, then go for a 15 mile drive, and then tighten them again. The reason for the second tightening is that during the first miles, the wheels work them selves in to the exact right position, and there for the nuts/bolts may be tightend a litle bit more.

Tightening the wheels more than spec, makes more harm than good.

I guess i slipped a litle bit of topic there, sorry about that. Correct anwer is: The cones of the nut's or bolts centers the wheels.
And if everything else looks fine on your swap, it should be totaly safe to drive.

Do it! And go and have some fun!