4350 replies to this topic

[Scuffers]

Actually, I think there are three versions applicable to a VX at the moment.... the names all get a bit mixed up, but basically, one is 16mm centre move, and only takes radial mount callipers at the rear (like the front), one is the same but for the std lug-mount brembo calliper, there is a new one that has the caliper mounts separately to make it modular, and the last one is the Race spec one for race cars only. the 'normal' ones are for everyday cars and trackday use, basically they allow you to lower the cars to the bottom end of road going levels (Typically ~110/120), they work with all known wheel combo's, only think you have to upgrade at the same time (if you have not already done so) is the toe links as they are double shear brackets for sphericals (as opposed to ball joints). the upside to this is that the cars roll centres are pulled back up to the 'right' area (without going into a text book, your just going to have to take this on trust - sorry). the effect of this from your perspective is it makes the car much more stable/predictable in cornering without having to rely on exaggerated geo's and spring/damping setups to try and keep the car stable, even if your not Lewis Hamilton, you WILL notice the difference on a track within the first lap (all assuming they are installed and setup right!). other upsides is they are lighter than steel ones, and MUCH stiffer, so no more self-adjusting toe depending on lateral load, along with having a much larger surface area to dissipated the heat from the bearing pack, thus they last longer by not getting cooked. All that said, for a road car, I would NOT be changing these first, the wishbone bushes/dampers/ARB are all higher priorities and will give more returns from std.

[Winstar]

other upsides is they are lighter than steel ones, and MUCH stiffer, so no more self-adjusting toe depending on lateral load, along with having a much larger surface area to dissipated the heat from the bearing pack, thus they last longer by not getting cooked.

What is the fatigue preformance of the Ali used for a road/track I seem to remember the Nitron ones used 7075 which has a farly low fatigue resistance/strength.

[Firthy]

Cheers Scuffers all extremely interesting info thanks for taking the time to post and explain

[Scuffers]

other upsides is they are lighter than steel ones, and MUCH stiffer, so no more self-adjusting toe depending on lateral load, along with having a much larger surface area to dissipated the heat from the bearing pack, thus they last longer by not getting cooked.

What is the fatigue preformance of the Ali used for a road/track I seem to remember the Nitron ones used 7075 which has a farly low fatigue resistance/strength.

7075 is the right stuff to use, the issue is you have to design them with the properties of the material in mind.

let me put it this way, I have run them on cars for over 8 years now, with zero fatigue issues, yes we have had some broken, but every time this had involved contact usually with a concrete wall first.

speaking personally, I would not get into a car and give it death of I had *ANY* concern over a single part of it, I have no wish to maim/kill myself.

for example, this car has a set on it from when it was built 3+ years ago...

http://www.youtube.com/watch?v=Ic7uMC3NQO4

the idea of doing 264Kmh with something that might break under load just is not worth thinking about.

Edited by Scuffers, 26 September 2012 - 04:35 PM.

[Nev]

Moving the hub height up only 16mm isn't anywhere near enough IMO, if it had been 35mm I would have bought a set. Instead I have been looking into things that only 2 people to my knowledge have ever done to a VX. However it is expensive and also has a moderate amount of risk so I am not keen. In essence Lotus chassis has limitations, which are hard to overcome: 1. Wishbones are too short. Longer ones have a couple of major advantages. To remedy this you have to cut away chaissis parts and strengthen the new take off/hard points. 2. New wishbones need to be designed with new higher roll plane in mind (approx 40mm higher for a track car, maybe 50mm for a race car). Rosejointed to transmit strains, less long/short ratio due to longer length, require less artifical camber/casteor adding. 3. Coilovers need to be moved inboard to reduce floating mass, utilising a push rod to operate. Geared fulcrum pushrods can use less heavy duty springs/valves as well. 4. Rear brakes need to be moved in board. Would require rear sub frame assembly rework to offer mounting points for the calipers to operate on the driveshafts near the gearbox (possible issues with unequal lengths). 5. Disc circumerance needs to be increased a lot and a new master cylinder with higher ratio installed. This will allow more clampage pressure and more moments of leverage to effect 2.0g+ braking required for racing. 6. Bigger rolling circum wheels/tyres, more width, increase the contact patch especially on the rears. This has worked a treat on my car and allows around 1.4 lateral g (I have yet to remeasure this again accurately BTW). 7. Rear subframe is weak and is not firmly joined to the car. It needs throwing away and replaced with a stronger item. The A-bars that attach to it from the rollover hoop need stronger (multi point) mounting points. This will reduce the major flex this item has. The problem is that doing that lot to the car to make it competetive would be so expensive that it is better to start with a better car in the first place - well thats my conclusion anyway.

Edited by Nev, 26 September 2012 - 05:02 PM.

[Scuffers]

with respect, that's mostly total horlicks! and 1.4 G? a std road car can just about muster that with half decent tyres. as for the 16mm, the race set are 45, but as I said, on a road going car, that's just not going to work out. Me thinks you have either been reading too many books or the like....

[Nev]

Fine. I knew I'd get flamed !

All my comments are for a competative race car (not a road car BTW).

Edited by Nev, 26 September 2012 - 05:07 PM.

[Scuffers]

Fine. I knew I'd get flamed !

not a case of getting flamed, more about how about backing up *any* of what you posted with real visible results?

for example, show me the datalogging/video/etc for you managing to pull a sustained 2G under brakes?

[Nev]

Read what I wrote carefully. As usually people are misreading me. I didnt say I had installed inboard brakes or new master cylinder or even new calipers or pulled 2g in my car. It is however my opinion on how to acheive decent braking whilst improving handling. ie the things I would attempt to do on a race car if I were building one. Trying to get over 2g braking is quite possible and clearly would give a comptative edge, hence my critique above.

Edited by Nev, 26 September 2012 - 05:14 PM.

[Scuffers]

So, like i said, Wild theory then. Look, i have raced many different cars, driven even more, outside of single seaters, your not noting to see 2G.

[Nev]

I can't understand "your not noting to see 2G" but I think I will bow out of Cliffies thread now as I can see you are opinionated and becoming polarised. However, I stand by my ideas on how I'd build up a race car, if you chose to do it another way thats fine.

Edited by Nev, 26 September 2012 - 05:53 PM.

[chris_uk]

nev do you mean sustained G or peak G?

[Nev]

Sustained (on a big roundabout for about 180 degrees) - I thought 1.4 was pretty good, though I was using an accelerometer in my phone to measure it, so there may be some margin of error in it. Also that was before my geo (which was previously terrible as my wheels were pointing all over the place), so things might be a bit improved on that value now.

Edited by Nev, 26 September 2012 - 05:48 PM.

[chris_uk]

i tried it and i think i got more than 1.4G doing the same, but i used a perf box.

[J4EY D]

Scuffers, its mind boggling how much you know and how quick you are on track... I need to start taking notes... And driver training Mike, It will be awesome if you're back next season! I'm going to try to make more rounds now that I know I can survive in a tent

[Firthy]

"I can't understand "your not noting to see 2G" but I think I will bow out of Cliffies thread now as I can see you are opinionated and becoming polarised."

Nev...... You my friend are clearly intelligent and have read a lot (and contributed a great deal which we are all grateful) ..... but you clearly have very little car setup experience.... which is what this forum needs at times.

"Sustained (on a big roundabout for about 180 degrees) - I thought 1.4 was pretty good, though I was using an accelerometer in my phone to measure it, so there may be some margin of error in it." - This sort of stuff doesn't help and the fact your car hasn't been on track yet......

Of course you are going to get a reaction from your first post... you clearly wanted one

Stop being so bloody sensitive!

Edited by Firthy, 26 September 2012 - 06:06 PM.

[luke.]

Scuffers you have a world of knowledge mate and i think the cars you have developed is proof in the pudding. Top work my man And i think i say this for the whole forum but you are a good asset to this forum

[Mike (Cliffie)]

Please don't take Scuffers to heart Nev, he is a far cleverer bloke than I am and trust me when I say this... He has far more experience and knowledge in setting up out little cars than most race prep companies and he may have had quite a lot of involvement with a car company beginning with L on the design and set up of their cars.

[RobNA]

Please don't take Scuffers to heart Nev, he is a far cleverer bloke than I am and trust me when I say this...

He has far more experience and knowledge in setting up out little cars than most race prep companies and he may have had quite a lot of involvement with a car company beginning with L on the design and set up of their cars.

Please don't take Scuffers to heart Nev, he is a far cleverer bloke than I am and trust me when I say this...

He has far more experience and knowledge in setting up out little cars than most race prep companies and he may have had quite a lot of involvement with a car company beginning with L on the design and set up of their cars.

Come on Nev, you have zero motorsport experience, let alone designing race cars. You may have read lots, but until you have years of experience putting it into practice you just cant state facts and claim "theories" against people that have been there and done that a thousand times before.

Nice to see some proper sense being spoken on here Scuffers

[MAXR]

Great Thread, good to read some interesting stuff again! Scuffers clearly has immense knowledge & his approach has been throughly tried & tested... And, He's an awesome driver, can't argue there either!