Is this SAFE????

[BQR280Z]

Hi Guys,

I'm 54 years old and an old school hot rodder, love my Z, but need your help. I ran into a good buy on some 17" wheels and my son talked me into trying them on the car. They needed complete refinishing so I painted them the color of my stripes. The offset was massive 42mm so they are mounted with 2" hub-centric adapters, but I don't know, they look kind of scary to me. I love the openness of the wheels and the fact I can see my discs, but???

Tell me your experience with adapters, I don't want the wheels to fall off while I'm pushing the Z through fun corners.

 

Thanks for input,

Bill

[naviathan]

Wheel adapters are used quite often on Z cars because of the offset issues. I won't say it's safe though. I've read about problems with studs snapping and wheels coming off and therefore I'll never try it myself.

[jdizzy204]

agreed. although lots of people use spacers, i would suggest finding better offset wheels

[rudypoochris]

I agree with the above comment. It just doesn't jive with me. There are ALOT of wheels out there, it just takes a little more work to find the right set.

[Armand]

I think you need more holes in your rotors.

 

But really, WHY SO MANY?!

[z-ya]

I think you need more holes in your rotors.

 

But really, WHY SO MANY?!

 

Yes, the most dangerous thing in your photos is the rotors. They can for hairline cracks that can cause the whole rotor to come apart. The adapters are fine. I am assuming that you mainly driver your Z on the street? Pickup a new set of Brembo or Mountain rotors and ditch those drilled ones. You will notice an immediate difference 1in your braking performance.

 

Pete

[ron260z]

ok this topic is one that i've never understood, and i've been waiting for a chance to ask this.

 

lets say his rim is 7 inches wide. the offset is 42. so in order to mount the rim he uses a spacer. the rim is now lets say a zero offset including the spacer.

 

my queston:

 

what is the difference in the amount of stress on the hub if you put a rim that has a zero offset on the car, vs. the rim with a spacer that is now a zero offset?

 

both rims are zero offset NOW. so why does one put more stress on the hub than the other?

 

the rims are both let's say 1 inch away from the inside of the fender.

 

it's not like one rim is sticking out more than the other.

 

i'm trying to prove this argument wrong, or be proven wrong and learn something.

[Bartman]

As far as the original question posted, I think that if the wheel adapters are well made they should be safe; however they should be lug-centric instead of hub-centric.

ok this topic is one that i've never understood, and i've been waiting for a chance to ask this.

 

lets say his rim is 7 inches wide. the offset is 42. so in order to mount the rim he uses a spacer. the rim is now lets say a zero offset including the spacer.

 

my queston:

 

what is the difference in the amount of stress on the hub if you put a rim that has a zero offset on the car, vs. the rim with a spacer that is now a zero offset?

 

both rims are zero offset NOW. so why does one put more stress on the hub than the other?

 

the rims are both let's say 1 inch away from the inside of the fender.

 

it's not like one rim is sticking out more than the other.

 

i'm trying to prove this argument wrong, or be proven wrong and learn something.

Here's a link to Skulte that addresses your issue. http://www.skulte.com/info_pages.php/pages_id/3 If the net offset is the same it doesn't create any more stress.

[johnc]

both rims are zero offset NOW. so why does one put more stress on the hub than the other?

 

No one has mentioned hub stress in this thread. Our concerns are the fasteners (wheel studs) and the adapter. And also the messed up rotors.

[ron260z]

so what is everyone refering to when they say things like "i would never use spacers"

 

why not? what's so bad about them.

 

bartman i read the link you posted and it says spacers don't put any stress on your hub, bearings, bushings or wheel studs. but if you use just slip on spacers it does make more strees on ONLY your wheel studs and NOTHING else.

 

so now i'm asking why do people hate using wheel spacers?

[ZR8ED]

spacers/adapters.. are a BIG difference. To clear my wheels (older wheels than in my sig pic), I ran a 1/4" SPACER to clear my brakes, and I used 1.5" wheel adapters for my rear wheels, and I was pushing 300+ ft/lbs of torque at that time, and I street drove and did some track time no issues. They did make me nervous the first few times on the track. Also note that I did this to fillup my flares, NOT to correct a fwd offset rim, so I was doing what we all talk about not doing.

 

I ran like that for a year or two, then spent big $ on the proper rims to fill my rear flares. No fears now. I still have 4.5" back space, but a whole lot of dish as well!

 

I have "heard" of full track z's running adapters with no issues, but have not personally witnessed and verified it.

 

Scott.

[naviathan]

so what is everyone refering to when they say things like "i would never use spacers"

 

why not? what's so bad about them.

 

bartman i read the link you posted and it says spacers don't put any stress on your hub, bearings, bushings or wheel studs. but if you use just slip on spacers it does make more strees on ONLY your wheel studs and NOTHING else.

 

so now i'm asking why do people hate using wheel spacers?

When using FWD rims on a Z the rim center coupled with the necessary spacers to fit pushes the weight placement out away from the hub. If you think about leverage, when we make our pry bar longer we create more force without increasing pressure. Ergo when we make our hub longer with a spacer we're creating more force on the bearings and the studs which can (no one is saying it absolutely will) cause more wear and shearing force on said components. Some people just prefer not to run that risk.

[johnc]

so what is everyone refering to when they say things like "i would never use spacers"

 

You'll have to ask the people making those statements. I've run spacers on all of my race cars in thicknesses from 1/16" to 1" without ever having a problem. Right now on my 350Z I have 1/2" spacers in front and 1/4" spacers in back. That car has seen speeds of 150mph in Turn 2 on the Cal Speedway oval. Nothing snapped, nothing flew off, the car didn't explode into a fireball and then run into a school bus full of children.

[JMortensen]

You'll have to ask the people making those statements. I've run spacers on all of my race cars in thicknesses from 1/16" to 1" without ever having a problem. Right now on my 350Z I have 1/2" spacers in front and 1/4" spacers in back. That car has seen speeds of 150mph in Turn 2 on the Cal Speedway oval. Nothing snapped, nothing flew off, the car didn't explode into a fireball and then run into a school bus full of children.

Likewise I used to wrench on a race Porsche that saw upwards of 170 and had thick spacers on the back with 335/35/18 Hoosiers. The spacers were thicker than 2", might have been 3", it's been years so I can't really recall exactly. The issue with wheel spacers is the strength of the studs more than anything else. If the center of the wheel is moved way out (like the Ferrari kit car posted on another thread), then you have a wheel bearing issue as well.

 

Ross at Modern Motorsports used to sell wheel spacers. He had a story about getting his 280ZX stolen and joy ridden until the car was driven off an embankment. The car was pretty much totaled as I recall, but his bolt on spacers were fine.

 

As to the drilled brake rotors, I think that's another overhyped "safety" issue. If those are the fronts then I think having them drilled that much is a bad idea because it reduces the mass of the rotor and that means that it can't absorb as much heat. If they are in the rear though I think that is probably OK, because they won't be doing as much work and the offset to losing the mass is the lighter weight. I've seen many racecars with drilled rotors like that. Look at a drilled Wilwood UL-32 rotor, that's how they come. Smaller rotor so only two rows of holes, but still a lot more holes than you'll find on a Power Stop or other brand. http://store.revolutionbrake.com/wilwood-disc-brakes-wilwood-brake-rotors-uld-32-drilled-lightened-straight-vane-rotors.html Again to use the race Porsche as an example, we used to send that thing out on cracked rotors all the time, and only changed them when the cracks bridged from one hole to the next, and never had a problem with a broken rotor.

[Bartman]

There seem to be quite a few people that want to say spacers and/or adapters aren't safe, but is there any evidence to back up that claim? If so, I'd like to see it.

 

Naviathan, I question the logic in your post. If the final offset for two rims is identical, but one achieves that offset with an adapter and one with a deep dish; I contend that the forces exerted on the hub and bearings is going to be the same.

 

I challenge anyone who posts that well made adapters aren't safe to post up evidence or logic that supports that position (other than the adapter lug nuts loosening up, which can be resolved with proper maintenance).

[naviathan]

There's nothing wrong with my logic. A deep dish puts the weight center of the rim at the hub where as a spacer extends the mount surface for the hub thereby increasing the leverage/force exerted on the studs and hub bearings. It's simple grade school logic, increased leverage increases force applied with a constant force exerted. It may not be a large enough increase in force to do any damage when your parts are good, but some people are slapping adapters and spacers on old lugs and bearings that can't take the added (slight or not) stress.

[z-ya]

For the street, adapters are fine. I probably would not run them on a road racer. Spacers are fine, as long as you have enough stud so that it protrudes beyond the lugnut. I run 1/2" spacers on the front of my road race Z.

[Bartman]

There's nothing wrong with my logic. A deep dish puts the weight center of the rim at the hub where as a spacer extends the mount surface for the hub thereby increasing the leverage/force exerted on the studs and hub bearings. It's simple grade school logic, increased leverage increases force applied with a constant force exerted. It may not be a large enough increase in force to do any damage when your parts are good, but some people are slapping adapters and spacers on old lugs and bearings that can't take the added (slight or not) stress.

Here's a direct quote from Skulte that contradicts your 'simple grade school logic':

 

 

Do the bolt-on wheel adapters increase the load on suspension parts?

The suspension loads are only affected by the centerline of the tire. Billet adapters usually correct offset issues when bolting newer style high offset wheels onto older cars that were designed with low offset wheels. A wheel with a 51mm offset and a 2" adapter is identical to the suspension as a 0mm factory wheel. This loads are the same on the wheel studs, bearings, bushings, because the wheel is in exactly the same location on the car. If it helps, imagine two identical wheels, with only the offset being different. Bolt the 2" adapter to the 51mm offset wheel, and it will measure exactly the same as the 0mm offset wheel.

 

http://www.skulte.com/info_pages.php/pages_id/3

[naviathan]

Here's a direct quote from Skulte that contradicts your 'simple grade school logic':

 

 

Do the bolt-on wheel adapters increase the load on suspension parts?

The suspension loads are only affected by the centerline of the tire. Billet adapters usually correct offset issues when bolting newer style high offset wheels onto older cars that were designed with low offset wheels. A wheel with a 51mm offset and a 2" adapter is identical to the suspension as a 0mm factory wheel. This loads are the same on the wheel studs, bearings, bushings, because the wheel is in exactly the same location on the car. If it helps, imagine two identical wheels, with only the offset being different. Bolt the 2" adapter to the 51mm offset wheel, and it will measure exactly the same as the 0mm offset wheel.

 

http://www.skulte.com/info_pages.php/pages_id/3

I don't understand how you can't see the obvious forces of leverage. The thing the statement made above isn't taking into account is that the lugnut mounting surface on the wheel isn't changing thickness when you get a properly fit wheel, but with a spacer or an adapter that's exactly what is changing.

 

| |

| |--| Normal Offset

| |

 

 

| |

| |-| FWD Wheel Offset

| |

 

| |

| |-|-| FWD Wheel with added spacer to offset.

| |

 

 

The point of force with the FWD wheel doesn't change in relation to the wheel with or without the adapter. It does change in relation to the hub mounting surfaced though which increases the force through leverage. I can't make it any simpler. Honestly though, do you really think a website that sells adapters/spacers is going to tell you that yes it will increase the stress on your car? Yeah that's good for business. I don't think the added stress is enough to cause excess wear or breakage on the car myself, but I do understand the point that others are trying to make when they say they won't use spacers/adapters.

[cygnusx1]

The likelyhood of failure of a wheel spacer or adapter is much more closely tied to the quality of the construction, the balance/alignment of the spacer, the grade of the bolts, proper torque on the bolts.

 

If the spacer/adapter is correctly made and torqued, the bolts should not see any shear force. They should only see tension. If the lugs get loose, they will then see shear forces which will more likely lead to a failure. The same applies to no-spacer wheels. If using a spacer, there could also be a longer bending moment on the lugs. Using a spacer that is hubcentric to both the hub and wheel is the best route for strength and reliability. In that case, the shear would not be delivered to the bolts in the event of loose lugs. If it were a machine and I was designing it, I would make it hubcentric. If that was not possible, I would use 2 to 4, 1/4" locating dowels to maintain alignment and absorb shear on both sides of the plate.

 

The biggest reason NOT to use spacers is the KISS principle. Keep it simple, stupid. One less thing to fail.

 

(edit) If done correctly and maintained properly, spacers and adapters are fine.