Wheels and offsets
Author
Discussion

Jabbah

Original Poster:

1,331 posts

183 months

Wednesday 17th July 2013
quotequote all
Looks like a previous owner put the wrong offset wheels on the rear of the Cerb resulting in the tyres rubbing on the inner arches every time I go over a bump or dip in the road.

Is there any way of changing the wheels offset or best off selling those and buying ones with the correct offset? They are Spider RL7s with 35 offset.

K4TRV

1,819 posts

281 months

Wednesday 17th July 2013
quotequote all
Depends on what tyres and rim width? What are you using.........???? (888s & R1Rs have broader shoulders than more usual road rubber [List 1A tyres that is])

But if you look at this link, you are running the correct offset and just a small fettle of the inner wheel arch would be the solution.

Have you coil-overs and running too low a ride-height, or too soft a spring?

Click on this link:http://www.pistonheads.com/gassing/topic.asp?h=0&t=725844

Getting a different offset is not, IMHO, the way to go.

HTHs

Trev

phazed

22,457 posts

233 months

Wednesday 17th July 2013
quotequote all
Everything he said!

Jabbah

Original Poster:

1,331 posts

183 months

Wednesday 17th July 2013
quotequote all
K4TRV said:
But if you look at this link,
Click on this link:http://www.pistonheads.com/gassing/topic.asp?h=0&t=725844
That was the link I originally looked at:

flyingdutchie said:
But if you are after the spider you should have ET 42 all round. The ET33 is what tuscans have at the back. It may fit, but it may rub at the innerarches
It has happened with two sets of tyres, the ones on atm are 595 RS-Rs, rims are 8J I think.

K4TRV said:
Have you coil-overs and running too low a ride-height, or too soft a spring?
It has Protech dampers but I tried raising the height and firming them up and it still rubbed on large dips on the motorway.

Edited by Jabbah on Wednesday 17th July 14:59

K4TRV

1,819 posts

281 months

Wednesday 17th July 2013
quotequote all
Jabbah said:
It has happened with two sets of tyres, the ones on atm are 595 RS-Rs.
I'd hate to repeat many others, but TVR bodies and location on the chassis, can at times cause individual problems.

I would also repeat the solution as you are running what are List 1B tyres like 888's & R1Rs, with very stiff sidewalls and broad shoulders which will exacerbate the clearance problem.

I think the solution is to raise the rear half an inch and possibly shave a few thou off the offending underneath arch, NOT to change your existing offset.

Edited to add that maybe the Protechs need a heavier spring? What are you running 325-ish? Upping to 400 can shorten the movement but not necessarily give a harsher ride? Cheaper than new wheels and a compromise of offset versus handling?

Just my pennies's worth ?

Trev

Edited by K4TRV on Wednesday 17th July 15:09

Alistair H.

1,173 posts

300 months

Wednesday 17th July 2013
quotequote all
Jabbah said:
They are Spider RL7s with 35 offset.
Jabbah,

They are either spiders OR RL7's...cant be both? looking at your profile pic, they look like 18 inch spiders. You should have ET42 all round...i.e four fronts. If your rears are ET33 then they most likely WILL rub..I know I had them and they did. Are all 4 rims exactly the same? or are the rears sticking out a little further?

Jabbah

Original Poster:

1,331 posts

183 months

Wednesday 17th July 2013
quotequote all
K4TRV said:
I'd hate to repeat many others, but TVR bodies and location on the chassis, can at times cause individual problems.

I would also repeat the solution as you are running what are List 1B tyres like 888's & R1Rs, with very stiff sidewalls and broad shoulders which will exacerbate the clearance problem.

I think the solution is to raise the rear half an inch and possibly shave a few thou off the offending underneath arch, NOT to change your existing offset.

Edited to add that maybe the Protechs need a heavier spring? What are you running 325-ish? Upping to 400 can shorten the movement but not necessarily give a harsher ride? Cheaper than new wheels and a compromise of offset versus handling?

Just my pennies's worth ?

Trev

Edited by K4TRV on Wednesday 17th July 15:09
Thanks for the advice Trev. Yeah, I've heard about the individuality of them.

I have tried pretty much everything with the geo and I think the springs were reasonably stiff but don't know off the top of my head. Didn't really want to take a grinder to the arches, and it is a bit more than a few thou...




And as it seems as though the Cerb prefers different offset on the Spiders was looking down that route. The previous ditch finder specials that it was sold with caught on the arches too so sure its nothing to do with tyre shape.

Jabbah

Original Poster:

1,331 posts

183 months

Wednesday 17th July 2013
quotequote all
Alistair H. said:
They are either spiders OR RL7's...cant be both? looking at your profile pic, they look like 18 inch spiders. You should have ET42 all round...i.e four fronts. If your rears are ET33 then they most likely WILL rub..I know I had them and they did. Are all 4 rims exactly the same? or are the rears sticking out a little further?
Yes, I don't know where the RL7 bit came from, they are definitely Spiders, and the rears are ET33.

Are the Spiders special in this regard or should all wheels have ET42 offset for the rear?

Alistair H.

1,173 posts

300 months

Wednesday 17th July 2013
quotequote all
Jabbah said:
Yes, I don't know where the RL7 bit came from, they are definitely Spiders, and the rears are ET33.

Are the Spiders special in this regard or should all wheels have ET42 offset for the rear?
Cerbera's need 4 "front" spiders. So that is 4 x ET 42. I also had new spiders from circa 2000 and TVR wrongly supplied the same as the Tuscans have, which is 2 x ET42 front and 2 x ET33 back. These simply don't fit properly and most cars with them on suffer from catching the arch, usually only one side and definitely worse with a full tank or track day tyres!! You need to get 2 new rims at ET42 for the rears and all your rubbing issues will go away. Trust me...mine did.

K4TRV

1,819 posts

281 months

Wednesday 17th July 2013
quotequote all
Alistair H. said:
Cerbera's need 4 "front" spiders. So that is 4 x ET 42. I also had new spiders from circa 2000 and TVR wrongly supplied the same as the Tuscans have, which is 2 x ET42 front and 2 x ET33 back. These simply don't fit properly and most cars with them on suffer from catching the arch, usually only one side and definitely worse with a full tank or track day tyres!! You need to get 2 new rims at ET42 for the rears and all your rubbing issues will go away. Trust me...mine did.
+1 ^^ what Alistair said - He didn"t get where he is today without knowing his onions. [see u at Loton?]
Trev

Alistair H.

1,173 posts

300 months

Thursday 18th July 2013
quotequote all
K4TRV said:
[see u at Loton?]
Trev
Yes indeedy!

Jabbah

Original Poster:

1,331 posts

183 months

Thursday 18th July 2013
quotequote all
Alistair H. said:
Cerbera's need 4 "front" spiders. So that is 4 x ET 42.
Thanks for the info Alistair. I was asking about that more because I was considering getting different wheels and from the other thread I got the impression Spiders were slightly odd size wise.