The shiny spots are evidence that the bolt was moving within the hole.......
The two pictures of the shiny spots are taken from opposite sides of the same bolt. It seems to me that the specific locations of the two discreet shiny spots indicate that the bolt was moving diagonally inside the "hole", which can only mean that the "hole" was too big for the bolt! The problem is not that the hole is too big, but that the bolt moved in the first place, as it is suposed to be fixated by the clamping force of the bolt+nut.

Interesting to note that on the Toyota powered cars the torque for this connection is so much lower (50Nm) than on the Rover versions (70Nm).

Of course they use different subframes, which may be the root cause of this reduction, but of course this also reduces the clamping force provided by the whole setup significantly.

Not sure if the toyota powered cars use 10.9 grade nut and balljoint shank for this application. The rover ones do, therefore the M10 can handle the 70Nm torque.

Bye, Arno. Stan, Arno: maybe one of you ought to measure the inside diameter of the hole the bolt goes through...both the tranny mount and the A-arm. Oviously, it's to late to do that on my car now, and it was not measured at the shop. I would be very interested in your findings and opinion after taking measurements. Doing so would put this little sub-debate to an end. I seem to remember a factory drawing being posted somewhere that the hole in the tranny mount was 10.15mm or something like that? In any case, it would be helpful too know what the diameters actually are, and also "what they should be" given the loads experienced by this piece on the track. Of course, the fact that so many people are finding these bolts to be loose on their cars does not help elither.
Stan, Arno: maybe one of you ought to measure the inside diameter of the hole the bolt goes through...both the tranny mount and the A-arm. Oviously, it's to late to do that on my car now, and it was not measured at the shop. I would be very interested in your findings and opinion after taking measurements. Doing so would put this little sub-debate to an end. I seem to remember a factory drawing being posted somewhere that the hole in the tranny mount was 10.15mm or something like that? In any case, it would be helpful too know what the diameters actually are, and also "what they should be" given the loads experienced by this piece on the track. Of course, the fact that so many people are finding these bolts to be loose on their cars does not help elither.
I will measure it on my car when possible. And I will inspect the 10 mm stud for signs of rubbing. But it is highly likely that the various holes are of suitable size.

The main thing, the predominating factor, is that the clamping force is greater than the loads presented to the assembly when the car is operated.

If a 100 pound horse jockey runs into a huge pro wrestler, he takes the worst of it. If the pro wrestler runs into the jockey, you call an ambulance for the jockey. Same basic idea. The clamping force holding everything tightly together needs to be sufficiently above the in use loads. it would be helpful too know what the diameters actually are, and also "what they should be" given the loads experienced by this piece on the track. The diameter of the holes are irrelevant. As explained before, the clamping force is all that matters. For hole size, there are two options - a press fit hole (zero clearance) requiring a press to install it, of a hole that the bolt can pass through. What size the hole is doesn't matter, as the bolt is not supposed to be free to move in the hole - if it's a couple of 10,000 thousands of an inch, or a quarter of an inch, any movement of the bolt will cause undue stress and wear.

Once again, the clamping force of the bolt is all that matters. Make sure that the nut/bolt is torqued properly. If the hole was smaller, that wouldn't keep the bolt from moving. It would just move a shorter distance. You'd still get shiny spots.

Many cars have suspension mounting holes that are a very loose fit around the studs or bolts that go through them. Yet, they do not get shiny spots, and they do not break or tear apart. Good alignment technicians know that they can loosen up bolts holding the suspension or chassis together, and use the tolerances in those holes to help extend the adjustment range of the car. UPDATE:

Lotus has some new text in the factory service manual (my bold):

DH.6 - SUPER SPORT SUSPENSION
To provide customers for 6-speed Elise/Exige with a track optimised suspension choice, a 'Super Sport'
suspension specification was introduced in early 2006 as a factory build option package comprising:
- Bilstein dampers with thread adjustable spring platforms and 10 position combined damping adjustment.
Remote reservoirs on front dampers.
Note: For 'Cup' and supercharged cars fitted with Ohlins spring/damper units, refer to Exige S/C supplement.
- Elise road springs (42.5 and 60 N/mm front/rear) uprated to Exige specification; 47.5 and 65 N/mm front/
rear.
- Stiffer front anti-roll bar with 5-hole adjustment and Nylon mountings.
- Rear suspension chassis brace kit (recommended for track use and/or A048 tyres)
- Lightweight forged wheels, 6.5J x 16 front, 7.5J x 17 rear.
- Yokohama A048 tyres (standard fit on Exige), 195/50 R16 front, 225/45 R17 rear. I seem to remember a factory drawing being posted somewhere that the hole in the tranny mount was 10.15mm or something like that?
Here's the drawing that I made of spacer, part of the factory "expensive" rear chassis brace:



The diameter of the hole through this part is 10.15mm as is the diameter of the hole in the factory replacement heim joint. I didn't yet get the chance to measure the diameter of the hole through the subframe.

marcw, nice work. I found it cool that the spacer your guys came up with is exactly as I envisioned. I haven't yet found a heim joint with a long enough threaded end, if I find one this would eliminate the need to fabricate the new longer toe push rod as your shop did (although the longer push rod could increase it's strength over stock). you guys are animals! the knowledge here is incredible... im going to have to read through this 3 more times to see if can understand any of it....

thanks for the research on all of this marc. it couldn't have been cheap to do (time or $$). i just want to drive my car on the track and not worry about the parts breaking off....

or having a forklift tow. please keep us posted on any updates or news. (although the longer push rod could increase it's strength over stock). Which would prevent the link from breaking in the even that the tire was hit or "curbed", instead transferring the force to the chassis, bending it...

Find the longer threaded Heim Joint - it could be the better solution in the long run. here's a link to some photo's of the Lotus rear brace kit - LOTAC05377



enjoy! thanks for the photos, i notice there is a threaded part with adjustablitly on the inside of the brace between the ball joints. what is this for? is it so it fits hand built cars which might not all be exactly the same or is there some other function. thanks for the photos, i notice there is a threaded part with adjustablitly on the inside of the brace between the ball joints. what is this for? is it so it fits hand built cars which might not all be exactly the same or is there some other function.
Best I can tell that's what it's for, to adjust the length of the crossbrace so it's contacting the pivot bolts. Probably a good idea since the crossbrace is bolted down in the center as well. You'd need the postion of the engine mount, and both pivot holes all to be perfectly the same to make a non adjustable piece. But i'm no expert, I just know enough to be dangerous. Marc, nice work. Our Toe Link Brace solutions are now in production.

We've developed two solutions. One that improves Track Pack equipped cars. And most importantly, one that will work with ALL Elise and Exiges. This solution is more complicated but will retail for under $500. We've test fit this on 3 different cars (Thx Rachel!). Neil is running this kit and we've been very pleased. Marc, nice work. Our Toe Link Brace solutions are now in production.

We've developed two solutions. One that improves Track Pack equipped cars. And most importantly, one that will work with ALL Elise and Exiges. This solution is more complicated but will retail for under $500.
Cool. When are you going to put it on the website? Got any pics? What rod ends are you using? Cool. When are you going to put it on the website? Got any pics? What rod ends are you using?

Shinoo,

Don't be bashful...we need details. I'm sure there are a bunch of people getting ready to purchase a brace. What's cooking? Shinoo has a nice system that does not require machining out the rear chassis brace and A-arm pivot holes. He showed me one of the prototypes at the WCLM. I wll let him fill y'all in on the details, but suffice to say, if you are considering the factory brace, dont pull the trigger until you see what he has come up with. And most importantly, one that will work with ALL Elise and Exiges. This solution is more complicated but will retail for under $500.
Make a bunch of these... I have a feeling you will sell out quickly!
Thanks for all your work on this!
(can I send you and pay for my order now??? ) We've been running two different solutions on our cars for a couple of months. BOTH feature the additional bracing to the chassis at the tranny mount.

Our solution for non Track Pack equipped cars will feature lighter (but plenty strong)tubular toe-links, Teflon lined heim joints, and will be Zinc plated. All required hardware and spacers will be provided. We've also got a nice little feature that'll keep those pesky nuts from coming loose too quickly.

The Heims are the longest lead time item for us at this point as they are very unusual. We should have a small batch ready in 4 weeks. Priced under $500. We've been running two different solutions on our cars for a couple of months. BOTH feature the additional bracing to the chassis at the tranny mount.

Our solution for non Track Pack equipped cars will feature lighter (but plenty strong)tubular toe-links, Teflon lined heim joints, and will be Zinc plated. All required hardware and spacers will be provided. We've also got a nice little feature that'll keep those pesky nuts from coming loose too quickly.

The Heims are the longest lead time item for us at this point as they are very unusual. We should have a small batch ready in 4 weeks. Priced under $500.
If the spherical rod ends are very unusual how do we get replacements and what will they cost? Also, what do you expect for life on a street car? Service life is one of the reasons that type of sperical rod end is not used on street cars and on race cars they have to be replaced as part of prep and maintenance. Also, what's the temp rating on that rod end? Thanks.