61 replies to this topic

[CHILL Gone DUTCH]

chill can you take your toe link bracket off to see if the crack originated from the bolt hole

 

Yes i will

but what i can see so far mine has missed the bolt wholes completely so unlikely to started there 

 

will get evidence when i remove it all completely  

[CHILL Gone DUTCH]

have any turbo cars had the issue and whats the difference 

 

[Spitfire Engineering]

have any turbo cars had the issue and whats the difference 

 

Yes, for sure though the differences seem marginal.

Sample size is too small to categorise and the damage is not consistent anyway.

The biggest surprise was the numbers involved, it is so rarely mentioned it was assumed it was a minor issue affecting a handful of tired, corroded heavy track cars but that is certainly not the case.

[MartynM]

Gaz , have you seen Nitron's design on an S2 Exige that can incorporate a brace bar with the toe links too? 

[Spitfire Engineering]

Hi Martyn, is it like like the Spitfire one on page 2 of this thread circa 2007? on the yellow 111R?  

I think the later Nitron one was a steel bar and was just a straight copy of the Lotus Motorsport version but all of these are toe link braces not subframe braces. The Toyo and VX subframe are not comparable. The VX needs a subframe brace and the trick is to design such a component which alleviates the issues but does not create it's own issues in the process.

 

It's worth noting even the 111R brace we designed right back then was mounted on bearings even though the non lateral forces were minimal on this subframe/RSJ, we wanted the subframe to be free to flex as Lotus designed it to as this controls fatigue resistance, the stress paths and compliance which in turn controls geo, handling, etc

 

 

 

 

 

 

 

 

Edited by Spitfire Engineering, 28 July 2018 - 08:02 AM.

[MartynM]

Fairly similar, it uses the factory cross brace steel bar with the bolt going through the bearing that is shared with the toe link arm - https://www.seriousl...ar-toe-link-kit

 

Gaz, I think it's great though how much effort, time and passion you guys are putting into for finding a engineering solution without it causing more issues or impacting on other components, I'm may also be interested in your plan A, pm me some details at some point if you like? 

[Spitfire Engineering]

Fairly similar, it uses the factory cross brace steel bar with the bolt going through the bearing that is shared with the toe link arm - https://www.seriousl...ar-toe-link-kit

 

Gaz, I think it's great though how much effort, time and passion you guys are putting into for finding a engineering solution without it causing more issues or impacting on other components, I'm may also be interested in your plan A, pm me some details at some point if you like? 

 

The design is more or less finalised now, just working on pricing and production.

[FLD]

Can't wait!

[Spitfire Engineering]

OK, pretty sure we have covered all the bases and are more or less ready to manufacture.

Please see the new thread "VX Brace offer" as this tells you all you need to know if you are interested.

[CHILL Gone DUTCH]

Is this caused by the support brackets

Anyone sufferedwith a cracked subframe with the oem style toe links

[Spitfire Engineering]

Is this caused by the support brackets

Anyone sufferedwith a cracked subframe with the oem style toe links

 

No, the cracks don't route through the bracket holes and you wouldn't expect them to really as they are the same panel as the main M10 bolt which also takes the wishbone loads. There is one possible exception which was the thread on Facebook but I never received a response from the OP so can only speculate but not publicly.

 

Yes, plenty of examples of cracked OE subframes, some claim never to have been tracked though not many are on their first owners so hard to confirm.

 

You would expect some correlation between uprated toe links and subframe cracks because the cracks are related to subframe stress which in turn are related to some degree with sticky tyres and extensive track work and many of these cars are on uprated toe links.

So correlation? - yes, but there is a similar correlation between those having a full seat harness and a fire extinguisher fitted and cracked subframes.

 

Cause and effect? - no evidence of that whatsoever and no pattern I could see from the responses apart from corrosion which is to be expected really.

 

 

 

 

 

[2-20]

Mine cracked on OEM toe link and at low mileage ( 35000 Kms) on LH side

[The Batman]

Why is it always lhs

[Spitfire Engineering]

Why is it always lhs

 

If you can work it out in the next ten mins I'll bring a bar of chocolate down with me  

 

Just go up a post and it should be obvious.

 

[Johnboyhgt]

I know a car on OEM links with the crack.

Sent from my SM-G903F using Tapatalk

[The Batman]

Why is it always lhs

If you can work it out in the next ten mins I'll bring a bar of chocolate down with me

Just go up a post and it should be obvious.

Lol I had only just woken up after 5hr sleep

That’s the excuse and I’m sticking to it!!

Subframe is waiting for collection now

If you can get or bring a brace down Or get one sent here this week I can see if it fits with a 2.5” tullet

[Spitfire Engineering]

 

 

Why is it always lhs

If you can work it out in the next ten mins I'll bring a bar of chocolate down with me

Just go up a post and it should be obvious.

Lol I had only just woken up after 5hr sleep

That’s the excuse and I’m sticking to it!!

Subframe is waiting for collection now

If you can get or bring a brace down Or get one sent here this week I can see if it fits with a 2.5” tullet

 

 

 

OK I will check it out thanks.

 

Most UK tracks are predominantly RH so the weight transfer is mostly on the LH wheels, as this is when the subframe suffers the most deformation you would expect to see more subframes damaged on the left side than the right. All things being equal of course.

 

[Tibbles Stryker]

So I take it this is another vx related issue in general and not caused by uprated toe links, I'm struggling to determine the ultimate issue behind this from everyone's posts above? So having bought and fitted uprated toe links will I have this issue sooner or later or does it affect all vx220 regardless?

[Spitfire Engineering]

So I take it this is another vx related issue in general and not caused by uprated toe links, I'm struggling to determine the ultimate issue behind this from everyone's posts above? So having bought and fitted uprated toe links will I have this issue sooner or later or does it affect all vx220 regardless?

 

So I take it this is another vx related issue in general and not caused by uprated toe links,

Correct, please see the post above.

There is no pattern to the cracking I can determine though a sample group of 50 is not exactly overwhelming.

Mileage, usage and condition would seem to be the largest factors but this data set is even smaller so not conclusive.

 

The toe links themselves are nothing to do with the cracking (one possible exception but no info from the owner) insomuch as they do not change the geometry nor the pick up points.

The spreading of the load by the double shear bracket is on the same face as the main bolt so academic.

The holes in the subframe are not relevant either.

 

But as mentioned they tend to be fitted to track cars which generate more force on the link so there is a correlation but no more than a fitted fire extinguisher or the fact the drivers are wearing racing boots.

 

will I have this issue sooner or later or does it affect all vx220 regardless?

 

Well that is what we are trying to avoid!

 

[Tibbles Stryker]

Fantastic, the answer I was after! Thanks for taking the time to respond, appreciated 👍