Rim caliper clearance

I took off my front rims today. They are Alessio F1 Rims or something like that and i noticed that there was a spacer on there. It says 8mm on it. Just wondering is this a safe size to have without bigger wheels studs? The rim only clears the caliper buy like 1-2mm

 

8mm is not a lot, but the longer hub bolts are cheap enough and worth going to the trouble.

Does your spacer have the centering ring to locate into the hub? - they are the best type to have.

It is a real pity that so many great looking wheels just won't bolt up to a Zed because of caliper clearance.

 

na they are just ones that u slip on and they sit there. What do you mean by the centering ring? Does anyone have a picture of any?

I might just have to go nissan and order some new bolts then, hmmm....

 

i doubt any 8mm is hubcentric so it's a floating type.

longer wheel studs or not, these kind of spacers are not safe period.

 

bin that shit michael,hubcentric bolt on's or nothing

 

As I understand it, the minimum meat required for a successful bolt on spacer is 20mm, though I have seen advertised bolt ons as thin as 15mm. Certainly no thinner.

Using such a bolt on spacer would therefore move the load bearing point at least 20mm further from the fulcrum. So unless the laws of physics have been repealed while I wasn't looking, especially the principle of moments, I would say that any bolt on spacer would produce a serious increase in torsional stress to every suspension component compared to a 8mm slip on spacer, hub centric or not. It's all a question of Newton-Metres.

Further, assuming a minimum of 20mm for the billet of a bolt on spacer, there would be a track increase of 40mm minimum, where the minimum legal increase is 25mm pretty much everywhere. So easy for Constable Plod to spot too - the car basically looks like a go kart.

Sure you could compensate for that by changing the offset of the wheels, but wouldn't it be simpler to just get a wheel that fits in the first place?

In summary I would go the 8mm slip on and longer studs over a bolt on every time.

 

thanks for the physics class Barry

Maybe Albert Einstein can tell me how you centre the slip on spacer ,nothing like an unbalanced wheel spacer at 100kmh ,thats the whole problem with them,they just slip over the studs and sit anywhere they want
Bolt ons sit exactly over the wheel locator and sit dead centre on the rotor

 

No problem - that stuff was about grade 9 level.

Don't get me wrong, I am no fan of spacers of any sort, but I do take odds with the view that bolt ons are always better. They can't be, because they are a minimum of 20mm thick, have a large rotational mass (usually made of steel), and move the centre of support further from the fulcrum. That loads up everything.

When it comes to aluminium spacers as thin as 3, 5 or 8mm, their weight compared to the unsprung mass of the rest of the assembly is trivial, as is the resultant moment of inertia. The worst you could expect would be a bit of wheel wobble at speed if you didn't centre them properly, but there would be a pretty large margin for error, and an easy fix.

A bit of wheel wobble if you get it a bit out is a whole lot different to the failure of a major suspension component due to excess torsional forces due to a major increase in the track of the car from bolt on spacers of 20mm or more.

I reckon most people using slip ons don't go to the trouble of fitting the extra length studs, and problems with modest slip ons are due more to that than anything else.

Given that just about all of us use after market adjustable camber arms, that adds an extra element of doubt to the use of any spacer.

That's my view anyway -everyone else is welcome to theirs.

 

oh well,youll get no W.A responses now,nice one lol

 

If you are using slip on spacers, shouldn't you also be using larger diameter studs? Since the wheel is not sitting on the hub, you would have an additional loading (shear) on the wheel studs. You would need to increase the diameter of the studs to give more area in the shear plane to avoid failure, but I have never seen anybody do this as it would require alot of work (hub modification, larger holes in the rotor and possible wheel to allow the larger studs to fit etc) which could explain why slip on spacers are illegal.

 

Most people run spacers to clear calipers or correct for having wheels that have incorrect offset, not to increase track. As long as the nuts are torqued up properly I can't see it loading up the hubs or arms any more than stock.

I need 20mm spacers to run my Work Rezax's so they clear the calipers, this will bring the offset to stock specification. Doesn't worry me in the least except for the powers that be just have a blanket ban on them unless OEM (i.e. old school 911)

 

I also needed a set of spacers for a set of rims that I'd purchased from this forum. I settled on a bolt-on kit from Just Jap (17mm from memory) and longer nismo studs. I too experienced strong vibrations at speeds over 100 KPH and under heavy braking.

After four months of use, one of the Nismo studs on front passenger side was shorn off, and the remaining four bolts were somehow rattled loose.

Of course, I never found out about it until it was too late. Going about 80 KPH by MRT in Sydney, it started to wobble something ridiculous - scary moment - and I quickly pulled in to their workshop. Had the mechanics there take a look, and they found the aforementioned problem. Basically, the wheel was hanging on by sheer friction alone.

The twenty metres traveled with wheel wobble was enough to bend the wheel out of shape.

I binned both wheel and spacers in favour of a Jap set that suited the Z. Never again will I use spacers on my car.

 

finally, some facts. thanks for sharing.

is this what you had? http://justjap.com/store/product.php?productid=17022&cat=0&page=1

 

And on my old 930 Porsche I had 3" (75mm) bolt on spacers, as necessary with the old school tub Porsches and Porsche rims. Never had a problem with 2 years of heavy track work and driving.

I dare say either the JustJap spacers where of questionable quality or you just plain didn't torque them up enough.

 

Laws of physics have been repealed while you were napping Barry

Take a 35 offset wheel for example, add a spacer to it on a zed and yes your entire argument is correct.

Take a 50 offset wheel, add a 15mm bolt on spacer to it, and you have a wheel sitting in the exact same position as the 35 offset wheel, so it's not always cut and dry, and as most people use a spacer purely to use a set of wheels which, basically, don't fit, then the effect of using a spacer is actually helping as it's moving the center of the wheel closer to where it's supposed to be. (in my highly technical language)

Bolt ons are safe only as far as the quality of the product and the person bolting them on.

 

That's because you have Volk spacers and they are probably worth more than some peoples wheels

And I agree with everything that Andy has said

 

im running 3mm hubcentric spacers. with upgraded nismo bolts that are 10mm longer than stock.. works a treat and no vibrations.

slip on generic ones are friggen horrible

 

3mm hubcentric? they must be really well made and very strong. usually the cheapo hubcentrics don't come in anything less than 15mm like the justjap ones.

 

heres the facts ........
I have 3 sets of them here and the quality is perfect 100%,no problems at all with them
Benny has been running these exact same ones for years with no dramas
I was running a set of them on my last black spur run with the evo,im still alive lol

As far as joes statements
1/they dont make 17mm hubcentric bolt ons
2/why he fitted nismo longer studs is beyond me,you dont need to fit longer studs with 15mm ones which is what i presume he had

Like Andy said,the spacers are as good as the person fitting them