Tire sizing/wheels

[dinanminicooper]

Hello - new with my Megabusa, and will be running Hoosier R6s on track, but just picked up some 21.5x8x13 Hoosier bias ply tires super cheap. They are SCCA formula FE tread tires.

 

Was wondering if anyone has any experience with these (tire pressure etc) and if anyone thinks they could go on 7" wide rims. Hoosier recommends 8" rims. I don't think I will have body/fender clearance issues. Think these could be more of a autocross tire rather than a road race tire for me.

 

Also, does anyone know what the bolt pattern/offset is for Team Dynamics 1.2 race wheels for the Megabusa?

 

Thanks again!

DMC

[JohnCh]

Westfield and Caterham use the same bolt pattern: 4x108. They also share the same offset for their 6" wheels at ET24, but Westfield uses ET35 for their 15x7 wheels. That places the outside of the wheel in essentially the same place, but the inside extends inward about 24mm. On my car, that would foul the front wing stays. Have you looked for an ET stamp on your current wheels? Most manufacturers have this, although sometimes it's hidden on surface that mates to the hub.

 

-John

[JohnCh]

Hmm... Westfield has made changes over the years, so I just did a search on WSCC and it sounds like the ET35 is no longer the current recommendation. According to posts 2 & 3 here, the factory is recommending ET24 for the Team Dynamics: http://forum.wscc.co.uk/forum/index.php?/topic/95634-seiw-standard-wheel-offset-23mm/

 

-John

[lancylad]

I have caterham prisoner wheels on my 1995 Westfield, 6.5 x 15 ET13. This wheel thing confuses me!

[ayseven]

Higher offset = wheel more inward

 

Less offset = wheel more outward

 

 

eg. 0 offset wheel gives a wider track than a + 45 offset wheel

 

You can measure any rim by checking wheel width, then measuring the distance to the centre of the rim (the part that sits against the hub) from the INSIDE edge, using two rulers. The difference between the half way point of the total width, and this distance from the inside edge, is your offset.

 

There is no way to tell what anybody needs, because all the cars are so different, and have their wing stays mounted differently (unless you have bog standard Westfields or Caterhams).

[lancylad]

Gotcha.. Cheers

[jlumba81]

Is there any factory wheel that will fit a 7? I'd like to be able to use those search functions that most tire/wheel sites have.