41 replies to this topic

[Marco Polo]

Another warning for track users around here...

Scary picture on my car (NA) :


Here is the place:


I also heard stories of this happening to some other people (Ricky again ? )...

This place appears to be a weak spot (the Rear Frame is different between NA and Turbo, it looks mutch stronger on Turbo)... With an external advice, I plan to renforce this frame with a brace holding the two "towers"... I let you know as soon as I have more info (by next week I think)...


(again)

[Foxy]

Would be nice to hear the VXL/Lotus take on this and the bolt issue...StuH?

[Mick43]

Crikey.... Marco what age/mileage is your VX please - and how many track days have you done ? If this is seen on other cars - it should be checked by Vauxhall - if of course dealers haven't already been alerted... ?? Mick

[Mick43]

Crikey.... Marco what age/mileage is your VX please - and how many track days have you done ? If this is seen on other cars - it should be checked by Vauxhall - if of course dealers haven't already been alerted... ?? It looks like a weld has failed ? Mick

[Marco Polo]

My Speedster is an August 2000 NA (build #0027)... I do around 6 track per year (third year in my possession now)... I try my best to avoid the kerbs... (but the biggest "bangs" on my chassis have been while driving on pothole on the roads !!! ) And it is definitively a crack in the steel... It has been fixed by welding the crack and by welding 2 small steel plate on each site of the zone (like a sandwitch).

Edited by Marco Polo, 27 February 2005 - 06:43 PM.

[meldert]

I have seen the same problem on Dudes racecar.

[clipping_point]

Are u using Yokos? II Edit! Read your profile. Well sorry, you cant put Yokos on it and increase curve velocity 10-20 km/h and expect that it has no consequence. No car is designed for that. Lotus usually keep their designs slimmed and light.

Edited by clipping_point, 27 February 2005 - 06:55 PM.

[earlystock]

How different is this to the Exige design. That uses Yokos. Sorry, but to suggest that a tyre change (and by the way a tyre that is standard on the VXR) excuses this is silly. There should absolutely be adequate margin built into any design.

[cheeky_chops]

How different is this to the Exige design. That uses Yokos. Sorry, but to suggest that a tyre change (and by the way a tyre that is standard on the VXR) excuses this is silly. There should absolutely be adequate margin built into any design.

arent R048's the race compound?? Not road 048s??

[Marco Polo]

Are u using Yokos? II

Edit! Read your profile. Well sorry, you cant put Yokos on it and increase curve velocity 10-20 km/h and expect that it has no consequence. No car is designed for that. Lotus usually keep their designs slimmed and light.

Indeed I use Yoko (048R LTS, Lotus spec 048 for Elise, Exige and VXR ! )

I completly agree with you Clipping_point, putting Yoko increase stress but the design of the chassis should allow some more stress than standard road use on Bridgestone...

Anyway, my post is more intented as a warning for track user not a shout at Lotus/Vauxhall/Opel designer...
(or just a little, as they apparently put a stronger subframe on the Turbo)

Edit: spelling

Edited by Marco Polo, 27 February 2005 - 09:17 PM.

[clipping_point]

Maybe one should put up som FAQ about Yokos and the VX, how the probs look and their cure (if there is any).

• rear subframe fatigue cracks
• hub bolts snapping
• rear toe-links bending
• more?

Also quoting Ricky 2772:

"btw, I replaced the 2 bolts holding the hub and shims in place with stonger ones, rated 12.0, instead of the stock 8.0 ones...having experienced the sudden breakdown on one of them while at 120kmh, it was not fun....
....so I decided to upgrade to a stronger alloy... now I feel better when pushing hard... "

Edited by clipping_point, 27 February 2005 - 09:00 PM.

[cicastol]

Also quoting Ricky 2772:

"btw, I replaced the 2 bolts holding the hub and shims in place with stonger ones, rated 12.0, instead of the stock 8.0 ones...having experienced the sudden breakdown on one of them while at 120kmh, it was not fun.... 
....so I decided to upgrade to a stronger alloy... now I feel better when pushing hard...  "

Probably doing this is not a really better solution,because higher grade bolt are much more less resilient,so they are stronger but are much hard and crack faster without warning(no deformation), because they absorb dynamically much less energy before cracking!!
Probably the best solution is to use the same 8.8 grade steel but with larger diameter bolts.....!!

Edited by cicastol, 27 February 2005 - 10:59 PM.

[clipping_point]

Could be true

• 8.8 Yield Stress 640 MPa 12 %
• 12. 9 Yield Stress 1100 MPa 12.9 8 %

...but the impact strength of the 8.8 is twice as strong as the 12.9. Could be interesting to know what Lotus use

Edited by clipping_point, 28 February 2005 - 08:08 AM.

[MacGyver]

Hi Marco

What mileage is your speedster?

If I'm not wrong the rear toe links must be replaced every 20000 miles (or 5 years) ... As said before, if they do break you end up with a vehicule "steering" from the wrong end

If this thingy is two old it may have got loose, thus generated some kind of over stress on the rear sub frame creating this bad crack.

Read this: http://secure.elisep...n-gb/p_442.html

[Marco Polo]

Hi, Thanks for the tip... My car is 4 1/2 year old (august 2000) and 32 000 km, but the rear toe links were changed 1 1/2 year ago... (while doing a geo the dealer broke one toe link !!! As they were old, I understood and asked to fully change both of them...)

Edited by Marco Polo, 28 February 2005 - 09:07 PM.

[Mosi]

Are u using Yokos? II

Edit! Read your profile. Well sorry, you cant put Yokos on it and increase curve velocity 10-20 km/h and expect that it has no consequence. No car is designed for that. Lotus usually keep their designs slimmed and light.

I agree to this, I guess the number of damages like this or describes in the Warning thread Nr.1 we'll see more often in the next years. Our cars builds up such a higjh level of gravity that the load on the bolts is even quite high.

So I presume those who could answer all these point with yes has a grat probability to be one of the next

- track use or hard road driving
- using bigger tyres
- dring the car when wet or melting salt is used because there is no grease around the bolts that would protect it from corrosion, look at the pics
- high milage (for such a light weight car)

[Thorney]

You've got to love forums. We know of 2/3 cars which have had some of these issues whereas hundreds a re driven on track (hard) every day - hardly data for a recall is it. It is sensible to check things like suspension mounts on a car of this kind (we always do when working on them) but this isn't "failure about to happen" level is it? However, its right to post this sort of stuff as a warning, re-read my post and didn't want to give the impression that this info shouldn't be shared only that we shouldn't suddenly all panic about it thats all

[cucharillas]

First on Spain to have a similar cracked rear subframe.

 

 

6 trackdays / year

AD08R tyres

Gaz gold pro 600lbs

No rust

Toe links installed a month ago, -800 km.

208.000 km , but almost 150.000 on highway and with care by previous owners

 

Today i´ll weld it, tomorrow we race a trackday with 800km trip on 2 days

Edited by cucharillas, 24 November 2017 - 12:03 PM.

[CHILL Gone DUTCH]

better to bend a track rod than cause this 

 

 

[Captain Vimes]

Presumably this is where the cross brace that comes with some of the kits (spitfire??) makes a lot of sense!

Edited by Captain Vimes, 24 November 2017 - 12:27 PM.