Boxhead, due to the different positions of 15" tyres compared to 17" tyres in the guards we were trying to run the same set of arms for all wheel choices. We already run different uprights for 15" wheels compared to 17 wheels & larger.
But decided to bite the bullet and also supply different length arms depending on whether the customer wants to run 15" wheels compared to 17" wheels. It's purely a cosmetic thing, the existing arms operated correctly and had the required strength etc when adjusted to support any wheel choice.
It's all because we are dialling in the look of the wheels/tyres exactly in the wheel arches. And want the owners to be able to fill the guards with whatever wheel/tyre combination they choose. The main issue is the additional bulge/bagging a 15" tyre has compared to 17" or larger tyre.
It is mainly a problem with fixed offset wheel choices, like pin drive wheels.
And customers can still fine tune the wheel/tyre fitment in the guards to the mm by adjusting the joints on the arms. Handy to cater for difference in tyre bulge between 17" & 18 tyres. Even handy if you are purchasing custom offset wheels as you can still fine tune fitment with the suspension to dial them in perfectly.
There are no mistakes like this, this product is dialled in to the nth degree. The development cost of this product is high. I believe much more time and money has been spent on the PACE 427 than any other Cobra replica kit in Australia. But I hope the results show that.
And due to the aggressive nature of the pricing we have optimised construction as much as possible and running two different arm lengths increases production cost slightly.
So those arms that have been pulled off are suitable for 15" wheels. Brad you should have gone with 15" wheels.
Actually what Cobra replica out there has different arm lengths & different uprights for different wheel diameters...none that I know of.