15 replies to this topic

[Muncher]

I'm working with SpitFire Engineering to develop some aluminium machined uprights/hub carriers to fit the S1/S2 Elise and the VX.

There will be a number of features to overcome existing weaknesses in the setup but at this stage I'd welcome any comments as to their design and problems in the current setup they could overcome.

* Massive weight saving over standard, probably 5kg per corner
* Improving weaknesses in the current bearing setup
* Ride height lowered as standard without changing wishbone angle
* Easier to remove so hub can be changed within minutes and not change the geo
* More room for camber adjustment
* Double sheer track rod end incorporating zero bump steer
* Wider choice of brake setups following on from them


It will take a few months to develop but will be a common item for all Elise derivatives.

Something like this:

[markv]

Nice one, defenitly interested Mark

[kipper]

Paul, you are turning out to be the suspension guru..could be a nice bit of kit, keep up the work..would be interesed when replacing our rusting casing iron lumps of suspension. Dave K

[Muncher]

Paul, you are turning out to be the suspension guru..could be a nice bit of kit, keep up the work..would be interesed when replacing our rusting casing iron lumps of suspension.

Dave K

LOL, not quite I'm just supplying standard parts, taking measurements, giving feedback and testing. There's also input from suspension and brake specialists. I sent my hubs off to Spitfire a while back to be machined and that's how I got to know them. The hubs weigh a ridiculous amount and the box I sent them in weighed about 40kg if I remember rightly! None of the stuff they do is priced for any real commercial gain, it's just done as a problem solving exercise and the enjoyment of producing something worthwhile.

If it can be made out of metal I'll look into what can be made

[techieboy]

Some new powder/plastic/rubber coated wishbones as well please whilst we're fecking around stripping the suspension. But liking the look/sound of those hub carriers.

[markiii]

my biggest interest is in weight saving but if you manage that lot as well I'm in :-) I realise it's way early days but any vague ballpark on price?

[JawZ]

B.A.D has made some for the Speedster :-)

[Muncher]

my biggest interest is in weight saving but if you manage that lot as well I'm in :-)

I realise it's way early days but any vague ballpark on price?

Off the top of my head I'd guess at £750-1,000 for all 4 corners, difficult to predict. Either way they wouldn't bother making them unless it could be better than what's already out there and cheaper. There's a few bits that I've suggested are made but they've said that there are firms making similar components who do the job well for a reasonable price so they're not interested in making a component unless it can be done better.

Techieboy - I can get wishbones made, or lengthened but I'm not sure many people would be interested in spending that kind of money on a complete set of standard sized and weight wishbones which look a bit nicer. I'm guessing you'd be looking at £1,500 for a set, plus another £450 for ball joints, bushes etc. That's even before you've paid someone to do it and have a geo reset. You could easily be looking at 3 grand if you paid someone else to do it.

It's probably best just to get your wishbones powdercoated (altough some don't recommend that). I asked sinclaires whether they had ever seen or heard of a wishbone failing due to corrosion and they hadn't so I don't think they're going to fall to bits any time soon.

[jasvxt]

A 4 or 5 stud hub option, would be good, and open up more wheel options

[Winstar]

Some new powder/plastic/rubber coated wishbones as well please whilst we're fecking around stripping the suspension.

But liking the look/sound of those hub carriers.

The current suspenion can be stripped and powder coated relativly easily, it's just time consuming

Now Aliminium wishbones like the new BMW's have would be cool.

[Arno]

Sounds interesting, but just letting you know that some are already on the market:

Rear GT hub: http://www.elisepart...products_id=575



Front GT hub: http://www.elisepart...products_id=572



(can of course be fitted with the 5-bolt hubs used on the VX)

These are set up for 4-pot front brakes and 2-pot rears though.

These also move the axle center line up by 10mm, so the car is lowered by 10mm without changing the wishbone angles. This is important if you run very low ride-heights. With the normal uprights the wishbones start to angle upward and that screws up your bumpsteer graphs.

Bye, Arno.

[mandarinvx]

But those come out at £1700 for all four instead of £750-1000

[VIX]

Interested but, like the Spitfire tie rod bits, probably not until a full suspension refresh next year. PS. Will all these items be produced on an ongoing basis or is this a one-off?

Edited by VIX, 26 January 2008 - 05:03 PM.

[Muncher]

Had another chat today, the weight losses probably won't be as much as I estimated, but still worthwhile. Arno, I'm aware of those but Spitfire think they can be improved significantly. I won't go into how at this stage and I don't want to belittle someone else's product Similarly there is a lot of room for improvement with the badster design apparently. You're right about the ride height and wishbone angles, Lotus intended the cars to be 10mm lower but had to raise them due to headlight issues.

[Arno]

Arno, I'm aware of those but Spitfire think they can be improved significantly. I won't go into how at this stage and I don't want to belittle someone else's product Similarly there is a lot of room for improvement with the badster design apparently. You're right about the ride height and wishbone angles, Lotus intended the cars to be 10mm lower but had to raise them due to headlight issues.

Sure.. No prob.. Just hope that the original S1 ali uprights won't be the 'template' for these as they are well known to be ummm.. let's say 'flexible'. Apart from cost that was one of the reasons Lotus went to steel uprights at the back of the later S1's.

The VX and S2 did get redesigned uprights though that are between the S1 ali and steel uprights weight-wise. They were actually developed as an practical example of an R&D project for the American Iron and Steel Institute by Lotus Engineering. PDF of the research floated around the net for a while, but seems to have gone now. Some interesting bits about the loads and the deflection of the piece compared to the alu uprights and the S1 steel ones vs. weight and cost.. (with the last bit of course very important for the bean-counters )

Good luck with the project! Should be interesting to see what comes out of it!

Although it's easy to sink into a 'featuritis' swamp you may want to keep an open mind to adding extra bolt holes that are spaced a bit wider to the front uprights to fit bigger calipers for instance (Eg. AP, Alcon, Brembo). Rears could possibly be a modular design to allow fitment of knuckle-mount calipers (eg. the OEM ones) or third party radial mounts (like the fronts). Perhaps my using some sort of adaptation piece for either if that doesn't compromise the rigidity of the mount too much.

Bye, Arno.

[Muncher]

Arno, you've pretty much summed up our plans there:)