BklynRX7

ok im seriously looking at buying some 25mm spacers to put my fd wheels on my fc once my 5 lug conversion is done. I see alot of emphasis being placed on the term hubcentric. from what i have uncovered in searchs this means that the weight of the spacer and wheel rest on the center of the hub and not on the studs.
Now my problem is I can find 5x114.3 spacers for mustangs but the center bore diameter is 70.5 while the fc's is close to 60. Does anyone know of any car with the same bolt pattern and bore diameter? Am i correct in assuming that running a larger bore diameter spacer would be dangerous? I know of places that custom make spacers but they use cast studs which seems very cheap and dangerous.

Also i saw someone mention in another thread about this that they got spacers that matched the fd wheels bore diameter. what does this mean, does it make sense?

Ill say agin, ive searched here extensively using the terms "3rd wheels" since the search doesnt pick up fd. and other similar terms.

BklynRX7

im looking at h&R's and the closest ive found is 64mm centerbore for a prelude. A site or company that makes some for us would also be appreciated.

ScrappyDoo

iTrader: (7)

Search for hubcentric rings, they fill the gap and rest the wheel back on the hub. They are always on ebay or check a local wheel shop they should have them or no where to get them.

BklynRX7

ive seen them online they say they reduce vibration. Are they safe? is what im really concerned with. Most likely fi they as safe im gonna go with the mustang kit that includes longer studs. I believe this will be almost as safe as stock. Im gonna ask some local shops about the safety issue.

Crash Test Joey

iTrader: (1)

Unless you are using a spindle mount wheel, hubcentric is moot. If you use the correct length studs with conical seat lugs the spacer doesn't matter. It's the face of the lugs fitting into the seats on the wheel that will center your wheel if tightened properly. If your lugs are properly spaced (and you'd know if they weren't) the wheel can't help but be 'hubcentric.'

Rxmfn7

iTrader: (4)

While that is true, wont all of the weight of the wheel be put upon the lug studs only, as opposed to being shared by the lup of the hub , such as stock wheels do? Thats what concerns me, and why I always use wheels with the proper centerbore, or use hubcentric rings. I dont want to be taking a hard corner at 70MPH and thinking in the back of my head " Hope my wheel doesnt fall off".. Ive actually known people to have their lugs break off when going to non-hubcentric wheels. Granted there were other factors involved, but it still is something to think about. If anyone has more experience with this, and would care to correct me, please feel free.

Crash Test Joey

iTrader: (1)

Don't know what heppened to my reply, I answered this yesterday. Anyway:

I'm no engineer, but look at it this way: When you turn a corner, the top of the outside wheel wants to pull away from the hub. The bottom of the inside wheel wants to pull away from the hub. The lugs/nuts are what is holding them on the car. The weight of the car on the hub "lip" is really not substantial compared to the forces acting on the lug nuts.

I'm curious where we might find some test results regarding the forces placed on the wheel/hub/studs of a car. I'm quite sure it's been tested by someone.

reza

I got 25mm H&R for Mitsubishi, it has 67.1mm center bore that matched the FD wheel.
The problem is the bore too deep, thus hitting the center bore of the FD wheel before meeting with the mating surface. Thus the mating surface of FD wheel and spacer has about 1mm gap.
This is easy to fix, by machining the 1mm off the spacer. Then the only question is will doing this reduce the strength of the spacer.

White_FC

While im no engineer, only a mere machinist, I can assure you that having a wheel only resting on the studs will induce some vibration.
If you have it hub centric it wont vibrate. There is a very good reason why just about every car made has a matching wheel/hub.

The studs keep it pressed onto the hub. If you don't have something to center the wheel on.. well it wont be centered will it? even if the wheel only moves a poofteenth of a mm w.r.t the hub if its not hubcentric, that is more than enough to induce some sort of vibration/wear and any sort of speed.


And to the original poster... Just go get one machined up at a local shop? I don't know how much your paying for these off the shelf ones but a custom made job should not be much more..

Bigretardhead

it won't neccesarily vibrate if the spacers aren't hubcentric. it just depends on when you tighten it. sometimes it will, and sometimes it won't. but if you DO get a hubcentric wheel, there's no way to bolt it on even the slightest bit offset.

BklynRX7

Thanks for the suggestions guys. Here is the theory i came up with

https://www.rx7club.com/showthread.p...=1#post3866311

tell me what you think.

CHINOOO

I had FD wheels on my S4 did'nt change anything, never had a problem. No vibrations or shakes. Pretty light wheels I may say. I used them for street racing. Dude don't get too technical. You're giving me a headache. J/K. I just purchased RX-8 wheels for my FC. Can't wait to throw them on but first I'm gonna send them out for chrome plating so they could be my show wheels this summer. This is Chino from Brooklyn by the way can't wait to see your Seven on the streets!

BklynRX7

WHat spacers did you use?

Icemark

Although technically not a car, the Toyota Tacoma alloys are all LUG CENTRIC.

In other words if you try and balance the wheel by using a hub centric adapter, your wheels will be out of balance. This is a common issue on Tacomas, and points out that a hub centric is not on all vehicles and that the lugs and their position really are the most important part of the balancing.

Sure its great when you can balance a wheel by its hub... its 100% easier, than having to use an adapter. But if the adapter is correct, when using a 5 lug set up, the lugs will always center the wheel.

CHINOOO

None. I used very wide tires in the rear and they had a tubbed look to it which was great since there was no tire rub issues. I wish I took pictures of them so you could've checked it out.

Crash Test Joey

iTrader: (1)

This is the case for probably 95% of the cars and trucks out there. I've personally never even owned a vehicle which required hubcentric wheels, and I've owned more than 50. A lot of money is poured into wheel R&D and part of it is making sure the lugs go through the wheel in the right place. If your bolt pattern (and the method you use to tighten them) is correct, your wheels will be fine.

White_FC

Ok, having never even heard of a toyota tacoma i didn't know that.. thanks Icemark.

so there is no through hole in the wheel? and no raised section on the hub at all?
bizare...

White_FC

That is wrong.

How can you say 95% of all cars and trucks don't have hubcentric wheels?

Sure I may not have worked in many car places, but I can tell you the whole time i spent working as a mechanic at a mitsubishi workshop EVERY car I took a wheel off was hub centric.
And I can tell you that one of the factors contributing to a good deal of all vibration problems that came in were due to people using after market wheels with a larger through hole. A particular case was a magna that was supposed to have the stock wheels on it (and it did) but had a bad vibration problem, took a long time to realise that this one came off the showroom with hub rings because of some dealer fitted wheels.
A quick 5 min trip to buy some from the wheel shop fixed the problem.

Icemark

Probably the Toyota Hi Lux down where you are.

There is a center hub hole, but it is oversized, and if you balance the wheel off of it (as with many Toyota/Lexus Vehicles) the balance will be incorrect.

White_FC

Interesting.... Didn't know hilux's were like that, so when you buy aftermarket wheels for them your at the total mercy of how well the company drilled out the PCD? wonder why on earth they did that... Ah well, i'm sure they had a good reason.

Crash Test Joey

iTrader: (1)

Because 100% of the cars I've owned personally did NOT have hubcentric wheels. None of them were Mitsubishis though. I have stuck with Ford, Chevy, Pontiac, Cadillac, Nissan, Buick, Dodge, Plymouth, Jeep, Mazda and Toyota. Almost all of them have had aftermarket wheels at some point, and not a single one has ever had a vibration problem. Well, there was one that I bent an axle on, but that doesn't count

BklynRX7

By any chance did you have a '87 gxl? The fd wheels i got came of an '87 gxl that i got from a friend of mine who bought it off a friend of a guy with an rx-2 on rockaway parkway. They were on the back with no spacers but I had bologna cutters in the front cause the tires had rubbed through.

White_FC

I'd bet they all came off the showroom floor with hubcentric wheels on them though....
I'm very suprised you never had a vibration problem with them.

My Rx-7 has had continual problem with wheels that have a larger center hole them the hub.. Nothing solves the problem except buying hub spacers.

I'm not talking massive, undrivable vibrations here.. just annoying ones.. everytime it's happened (a few different wheels) it's been around 100km/hr..

NZConvertible

I concur with the Aussie. The R32 Skyline wheels I've just fitted have a bigger center-bore than the Mazda wheels and have induced a bit of vibration over ~110km/h. I'm going to get some center-bore spacers machined up.

This is always a hit and miss affair. Sometimes not having a matching center-bore causes a problem; sometimes it doesn't. But hubcentric wheels are far more common than non-hubcentric. Any wheel/tire fitter will tell you that.

Crash Test Joey

iTrader: (1)

Nope. I've bought over 15 of them brand new. Maybe I just have better luck with not having vibration than you do