TVR Cerbera Hubs for Kit Car
TVR Cerbera Hubs for Kit Car
Author
Discussion

MrNickB

Original Poster:

44 posts

162 months

Saturday 1st December 2012
quotequote all
Hi,

Firstly, an apology. I'm not a TVR owner, although if I didn't already have an Elise I'm sure I could be persuaded. My reason for posting here is that you chaps are undoubtedly the experts for all things TVR.

I am working on the design for an overpowered, over-aeroed and under-weighted single seater, with the intention of fully drawing and CAD modelling the car before I start building mid next year. This isn't another pie in the sky idea; I have experience in building cars and have backup from various professionals in F1 and elsewhere, and I have the resources and tools to follow this through.

I've discovered that the Cerbera extruded uprights look like great options for the four corners of the car, but I will need to design wishbones and model the suspension geometry with 305mm wide x 660mm diameter tyres.

Ideally, does anyone have a TVR Cerbera upright that I can borrow and draw up? Even better still, does anyone have two pairs of these sitting in a garage pile that they'd like to convert to cash? I don't mind about calipers and brakes, I can deal with those later on; key things now are working out the suspension geometry so I can locate the hard points on the car chassis and build a full size wooden mockup. I'm based south of Croydon.

I promise updates as I start the build!

Nick


MrNickB

Original Poster:

44 posts

162 months

Saturday 1st December 2012
quotequote all
Slight correction, based on research... I'd like to use the front uprights on all four corner, and run toe links on the rear. So drawings or samples of one of the front corners is all I need.

cymtriks

4,561 posts

269 months

Saturday 1st December 2012
quotequote all
Some years ago there was a problem with TVR hubs cracking. The design was changed. I don't know anything more about this but recall it being on PH.

I've tried a search but nothing came up.

Just check that you get the modified design.

RichB

55,500 posts

308 months

Saturday 1st December 2012
quotequote all
cymtriks said:
Some years ago there was a problem with TVR hubs cracking. The design was changed. I don't know anything more about this but recall it being on PH.
Been around TVRs for 20 years and never, ever heard this. Not saying it's not true but what I can say is that the early rims used on the Cerbera used to get hairline cracks and were re-worked. You may be thinking of this?

As for expert advice on Cerbers, why not post on the Cerbera section there are some experts on there.

Gazzab

21,583 posts

306 months

Saturday 1st December 2012
quotequote all
You should speak with Julian. Spitfirev8 on here....

Jasper Gilder

2,166 posts

297 months

Saturday 1st December 2012
quotequote all
Have a chat with Andy or Adrian at Central TVR, they do a lot of work on Cerbs and I have a niggling feeling they may be about to break one

MrNickB

Original Poster:

44 posts

162 months

Saturday 1st December 2012
quotequote all
Thanks guys, really appreciate that.

If there are any issues with hubs cracking, it would be good to know. In my application I'll probably be driving them harder than in a TVR, due to size of tyres, extra load from downforce, and a bi-turbo 4.2 V8. If the issue was actually with wheels/rims, that's less of a problem as I'll use aftermarket 5x114 rims to fit tyres of the desired size, rather than TVR OEM.

Gazzab

21,583 posts

306 months

Saturday 1st December 2012
quotequote all
the cracked uprights were part of a recall back in 98/99 time. Doubt there are more than one or two cerbs out there that made it through the net.

Gazzab

21,583 posts

306 months

TA14

14,332 posts

282 months

Saturday 1st December 2012
quotequote all
RichB said:
the early rims used on the Cerbera used to get hairline cracks
Wasn't that just the 18" ones?

RichB

55,500 posts

308 months

Saturday 1st December 2012
quotequote all
Gazzab said:
You should speak with Julian. Spitfirev8 on here....
Is that Joolz? If so I remember he was 'the man' for Cerberas back in the days.

spitfire4v8

4,021 posts

205 months

Saturday 1st December 2012
quotequote all
hi. yep the very early cerb hubs were fine, thick castings that gave no trouble. Then they changed to a thinner casting that fractured when the bearing outer corroded and swelled (steel carrier in aluminium hub). These hubs were the subject of the recall. Very early cars didn't get recalled as their hubs were fine. As said above you'd be hard pushed to find any of the fragile hubs in existence as it was a DOT recall not a factory one as such so HAD to be carried out I think?
If you're drawing up a hub why not do one from scratch though. Or have a word with Guy Evans at Nitron .. when he and colin blower were looking into a vx220 race series I seem to remember them settling on a merc S class bearing as the best available at the time?

MrNickB

Original Poster:

44 posts

162 months

Saturday 1st December 2012
quotequote all
Thanks for Guy and Colin info. I'll have a look at that hub.

From what I've seen of the TVR hub (TheTVRShop), the position of the top ball joint can be put in a number of horizontal positions. This is useful as it means I can set the line through the ball joints to hit the correct spot on the road (~1.5" inboard of the centre of the tyre contact patch), dialled in for the ET of the wheels I end up using.

Where possible, I want to use OTS parts that are 95% close to what I would design anyway. There's a lot to be said for someone else having done the testing, i.e. recalls!

MrNickB

Original Poster:

44 posts

162 months

Saturday 1st December 2012
quotequote all
Here's a not-to-scale version, based on guesswork on a cold winter's afternoon...


camel_landy

5,418 posts

207 months

Saturday 1st December 2012
quotequote all
Nick,

Where in the country are you?? If you're anywhere near N Wilts, you're more than welcome to pop over to my place as my Cerbera is currently in bits.

I haven't completely stripped the front hubs but you'd be able to get most of your measurements.

Drop me PM if interested.

M

Tafford

280 posts

252 months

Sunday 2nd December 2012
quotequote all
Hi - I've got a pair spare you can have - drop me an email and I'll send some pics if you like.

MrNickB

Original Poster:

44 posts

162 months

Monday 3rd December 2012
quotequote all
I've now bought two used Cerbera front uprights, I should have hands on them in the next week or so. I'll post drawings here once I've done them, if anyone needs CAD or dimensions feel free. Thanks, Nick.

plasticman

907 posts

275 months

Monday 3rd December 2012
quotequote all
The Uprights are fine but the bulky jeep wheel hubs that they are designed for spoil them . Have you not considered elise ones ?

MrNickB

Original Poster:

44 posts

162 months

Wednesday 5th December 2012
quotequote all
I've got an Elise with the original extruded hubs, and definitely considered these. The Elise hubs have two downsides though, in my opinion.

Firstly, I think the bearings are a bit fragile, I've been through at least one on each corner in 40k of driving. The Jeep bearings on the TVR are substantial, but on the upside that means I'm not going to be too concerned about strength.

Secondly, the TVR hubs can be changed with small tools, whereas you need a press to get the bearings out of an Elise. Unlike the designers of the Elise, I'm keen on accessibility and ease of maintenance, especially when at a track.

Thanks to readers here I now have one set of front hubs in my garage, and am hoping to organise myself to get another set sent across next week. Once again shows what a fantastic place this is for enthusiasts, and I will post the drawings of a corners for your amusement when they are available!