wheel offset.

[cerdad]

I have a 98 car on spiders,i guess they are not original, the problem is that the tyres touch the inside edge of the wheelarch over bumps,the geometry has been checked and is ok, i am assuming the wheels may not have come from a late cerb but another tvr so the offset may be wrong, does anyone have the figures?.
Its on Gaz which are crap .

[Jhonno]

Fronts or rears?

[Random24234]

From what i can tell after asking this quite a few times the rule of thumb for the spiders is :-

18x8.5 ET 42 fronts & either 18x8.5 ET 42 or 18x8.5 ET 33 (lucky dip?)

[Luckyone]

My 98 runs spiders, the fronts do catch like that too, I had the ride high set a bit too low, there is a note of the correct ride hight in the sticky threads up the top.

It’s possible the later cars may have had more clearance in the arches. I’m going to cut away some of the arch & remake it higher up + run the car a bit higher when it’s back together.

I think Rids trimmed his arches to run his 19s too.

[Vee8ight]

What size tyres and how low is it?

[Vee8ight]

Mine is a 97 on spiders and standard ride height and doesn't get anywhere near the arches, however you can sleep under the arches!

[cerdad]

Rears 255 35 18 and the ride height is standard ,about 20mm between the tyre and the arch.Its on Gaz which are awful,how do you measure rim offset

[Vee8ight]

cerdad said:

Rears 255 35 18 and the ride height is standard ,about 20mm between the tyre and the arch.Its on Gaz which are awful,how do you measure rim offset

I don't think that's standard ride height as I have 2 inch above my wheels!

[Vee8ight]

Rear spring should measure 195mm with wheels on the ground

[Vee8ight]

And damper should measure 353 mm from end to end

[ridds]

Probably got short shocks on the back. I have 10" springs on the rear and 9" on the front from memory.

Rear arches were trimmed on the RH side to fit the 19s but the 18s with slightly larger tyres rub worse than the 19s.

LH arch was fine, don;t you love had laid bodies.

[Luckyone]

cerdad said:

how do you measure rim offset

Like this

I measured the old 17" RL7s as ET40 if thats any help.

[K4TRV]

Luckyone said:

Like this

I measured the old 17" RL7s as ET40 if thats any help.

It's usually stamped on the inside of the rim: ET33 or ET 42

HTHs

Trev

[Steve_T]

My recollection is my 17" RLs were marked ET41.

[Luckyone]

Mine had been reconditioned at least once & so the markings were illegible.

I measured the offset with the tyres still on so ET41 was only 1mm out, not too bad!

[cerdad]

how do you measure the offset?

[K4TRV]

Luckyone said:

cerdad said:

how do you measure rim offset

Like this

I measured the old 17" RL7s as ET40 if thats any help.

As previous posting, ^^ see above??

T

[cerdad]

thankyou for that .