Hi all can any one tell me the thickness of my front and rear anti roll bars please need to order some bushes and theres lots of diffrent sizes its a jdm swb slicktop tt im am putting a na subframe on but think im gona use the tt rear bar as i think its thicker thanks taff.

I think the JDM were thicker than the UK ones. I can measure my JDM one tomorrow if know one knows off hand.

I think the JDM were thicker than the UK ones. I can measure my JDM one tomorrow if know one knows off hand.

 

It's the other way round mate, UK is solid JDM is hollow. Not sure if they are different diameters though.

Made this a few years ago :

 

Uk anti roll bars are considered an upgrade.

Im confused steams says uk bars are solid picture says hollow .

Im confused steams says uk bars are solid picture says hollow .

 

Me too, I could have sworn that the uk bars are solid. But Yowser does know his stuff, so more likely that I'm wrong..lol

I couldnt say for sure right now...it was a good 5 or 6 years ago now that I looked into ARB's and took that pic.

 

However, Solid vs Hollow doesn't make much difference - the greater torsional rigidity is a product of the larger diameter.

Edited July 23, 201312 yr by Yowser

Solid vs Hollow doesn't make much difference - the greater torsion comes from the larger diameter.

 

That can't be strictly true, otherwise the whiteline and other aftermarket arb available are still not up to the performance of a uk model oem bar?

Uk cars have lots of extras, bigger oil coolers, trans and diff coolers, adjustable rear suspension etc so it would stand to reason that yes it makes sense for them to be bigger/better. Which what I've always been Rolfing arb are an upgrade.

That can't be strictly true, otherwise the whiteline and other aftermarket arb available are still not up to the performance of a uk model oem bar?

 

The Torsional Stiffness is relative to the diameter to the 4th power. (2nd moment of Intertia). The outer surface does the bulk of the work. In relative terms, based on a 2.5mm all thickness, a 26mm Diameter hollow would have approx the same stiffness as a 24mm Solid tube - Taking into account the same material use.

 

Materials properties matters too, the shear modulus of steel differs by its carbon content and heat treatment processes. Im not familiar with the different steels used between the stock bars and aftermarket, but its a potential factor.

 

But when it comes to an Antirollbar, the length of the connecting arm has a significant affect.

 

The example used in my picture is non adjustable, but typically you can alter the moment acting on the shaft with adjustable antiroll bars, with different mounting holes on the connecting arm, allowing to to have the same affect of reducing or increasing torsional stiffness. This is the big selling points of Uprated Adjustable anti-roll bars.

Edited July 23, 201312 yr by Yowser

Ok my Jspec tt has a 26mm front arb and a 21mm rear arb which are hollow. Just been out there with the vernier.

One of mine is an NA and the other a TT, both rear and both JDM, both 21mm.

One of mine is an NA and the other a TT, both rear and both JDM, both 21mm.

 

What year (or series) is your NA ?. Its possible the narrower 17mm was replaced by Nissan to be the same as the TT version as standard in a later series. I dont recall which year that 17mm one came off, but I would imagine a Series 1.