73 replies to this topic

[james4563]

I've spoken with BoT and they advise that the main problem is probably the quantum blacks I have. Apparently they replace a lot of quantums with nitrons because the valving is better. I've only had my quantums for about a year. They recommend it might be worth considering replacing my quantums and if I'm not happy that the car feels better they will put the quantums back on free or charge. Nitrons ntr 40 with something like 450/550 springs even for road use. It will not be too harsh apparently due to the much better valving in the nitrons.

Edited by james4563, 21 March 2018 - 09:19 AM.

[james4563]

They also said it's running too much camber and for road use they would set front toe basically straight. The extra camber will make it feel skitty on the road.

Edited by james4563, 21 March 2018 - 09:21 AM.

[Mattyboi]

I'd try the geo changes before buying another set of coilovers. Many people use Quantums with no issues. Start with the the cheap things first.

 

I'm not saying one brand of coilover is better than another but new suspension is going to be ~six times the price of a geo set up. Most people wouldn't be able to split hairs between quantum's and nitron's on the road but they would notice a bad geo set up.

Edited by Mattyboi, 21 March 2018 - 09:40 AM.

[james_ly]

I'd raise the ride height, try 10-15mm each side and report back? Might take a few hours but won't cost anything.

[james4563]

I will have a look at ride height of the weather holds out this weekend 😁 I might have been wrong and it could be 120/130 but I will double check. Is 120/130 a good height to be aiming for? I will of course get the geo done right before changing coilovers, for the sake of 1 hour drive and £210 it'll be a lot cheaper if that fixes it! I got the impression that BoT think I may still find it feels the same and they really don't rate the quantums at all.

[Nev]

Hi James,   I'd suggest setting the ride height, camber and toe to OEM, use OEM profile tyres and you will almost certainly see a big improvement. You could easily DIY this yourself, it's not hard, just a bit time consuming and very rewarding. If you do, be sure to datum your garage floor, even a few mm inaccuracy will affect things, I have done a small write up here of the basics (scroll down): https://sites.google...07---new-engine   When these cars came out of the factory (like most Lotus') they were a handling sensation, designed and setup by genuine experts. Thus deviating away from the OEM setup (for a road car) can/will lead to poorer handling unless you really know why and what you are doing.   Resetting the geo yourself would cost next to nothing BTW, you can lookup how to use the string and pole method online and make your own camber measuring tool out of scrap wood etc. Accuracy of DIY geoing can be very good if you take care, people get misguided into thinking "laser" tracking is far better. While you are under the car you should investigate for: 1. Worn ball joints. 2. Worn bushes. 3. Worn pinion gear (or incorrect pre-load) in the steering rack. 4. Worn coilovers. 5. Loose/worn UJs in the steering rack.   HTH.

Edited by Nev, 21 March 2018 - 11:02 AM.

[Nev]

I will have a look at ride height of the weather holds out this weekend 😁 I might have been wrong and it could be 120/130 but I will double check. Is 120/130 a good height to be aiming for? I will of course get the geo done right before changing coilovers, for the sake of 1 hour drive and £210 it'll be a lot cheaper if that fixes it! I got the impression that BoT think I may still find it feels the same and they really don't rate the quantums at all.

 

I think OEM is 140f/140r (assuming OEM wheels with OEM tyre profiles), the bump curve is strongly logarithmic, so the further your deviate away from OEM ride height the more dramatic the bump steer (particularly on the rear with the very stubby wishbone arms).  

Edited by Nev, 21 March 2018 - 10:44 AM.

[chris_uk]

I spec the gaz monos we sell to 400/500 for road settings.. and that seems to work really quite well. 0 toe is because under bump (compression) you gain toe out, you get a slightly worse turn in but less chance of understeering mid corner to exit (track obviously) on the road it will just feel slightly damped and not as darty. To be honest, for just standard road driving there is little wrong with the standard geo really.

[james_ly]

I've got some standard Bilsteins in the shed you can buy...

[Arno]

It often feels quite wavey/floaty on the motorway at around 70. It feels horrendous on some other roads too, the steering seems to jerk excessively, although it does depend on the surface.

 

Perhaps an odd question.. But what tyre pressures are you running?

 

'Book' values are usually too high on these cars and many regular tyre shops tend to inlfate to 2.4+bar which is way too much and makes it feel like driving on eggs.

 

If you're not already lower, drop the pressure at the front to around 1.6 bar and the back to 1.7 and see if that makes things more relaxed at motorway speeds.

 

BTW do you know if the last alignment was done with the proper ballasting of the car? All quoted figures from Lotus and Vauxhall are with 1/2 tank of fuel and 75kg of ballast in each seat. Can be aligned fine without that, but you can't use the listed values for toe and camber/caster anymore as they will not result in the same behaviour.

 

I suspect the original alignment was done with ballast and perhaps even with only driver-side ballast if they asked if you're driving the car alone most of the time. If it's then (re) checked without ballast it may seem quite 'off' but it isn't.

 

BTW..

 

The PZero's the S1 elise came with were the original Pzero Asymetrico's that were ok-ish for the time but pretty dysmal in any but the most dry conditions.. And have been out of production for 15+ years now The VX/Speedster like the S2 elise was originally set up with propietary Bridgestone RE040 tyres which by now are also no longer available and frankly also not that great anymore.

 

Edit: if you're running 110 front without steering rack riser plates fitted then front bumpsteer (toe change with wheel travel)  will be quite agressive..

 

Bye, Arno.

Edited by Arno, 21 March 2018 - 01:30 PM.

[pete-r]

I would definitely start with the cheap/free basics as previously mentioned... Tyre pressures Play in suspension Wheel balancing Play in steering rack Reset the shocks. Wind them up to full hard, then soften them by counting back the clicks with say 2 more clicks on the front. I go 10/12 with 300/425 springs but whatever suits your springs obviously. Do that then see how it feels and you can adjust from there. Id be a bit miffed if a specialist told me I need new shocks to fix a handling issue on a car with adjustable suspension without even seeing the car.

[james4563]

Arno, I'll try lower pressures you mentioned on my drive home and see how it feels. I have run various different pressures but normally around 24/26 psi. I'm not sure if ballast was used or not. I have again had mixed comments when I've asked people to ballast it, some saying it'll make no difference and others saying it's critical. I don't know if Matt used ballast, but the place near me certainly didn't. I have a alignment jig I used for my previous car, so I may get that out ballast the car properly and then see where the geo is at. As far as I am aware, based on the last checks I did. I don't have any play in the suspension. Bushes and ball joints are basically new, only the bearings have not been done however I don't feel any play in them when checking each wheel. I didn't speak with jez because he wasn't in at the time and I'm sure they would do a geo for me if I requested it but the general advise was that the quantums are crap.

[james4563]

Oh and I did refurb the rack only a few months ago too. Preloaded everything to OEM specs.

[PaulCP]

Having ditched Nitrons for Quantum Bkacks a few years back I found the Quantums a tad better insomuch as they performed no worse than the Nitrons on track but were much more compliant on the road. Travelled the length of France taking in 3 track days in a week twice and never experienced any problems with them. No doubt Nitrons have improved since the ones I had but I can't see how the Quantums can be to blame if they are in good shape. As others have said, geo would be my starting point but MBR rarely gets it wrong

Edited by PaulCP, 21 March 2018 - 02:55 PM.

[james4563]

Paul what spring rates did you run on your blacks?

[fiveoclock]

I'd try the geo changes before buying another set of coilovers. Many people use Quantums with no issues. Start with the the cheap things first.

 

I'm not saying one brand of coilover is better than another but new suspension is going to be ~six times the price of a geo set up. Most people wouldn't be able to split hairs between quantum's and nitron's on the road but they would notice a bad geo set up.

He's had a money back if not satisfied with Nitrons deal. Why wouldn't anyone go with it?

[fiveoclock]

I would definitely start with the cheap/free basics as previously mentioned... Tyre pressures Play in suspension Wheel balancing Play in steering rack Reset the shocks. Wind them up to full hard, then soften them by counting back the clicks with say 2 more clicks on the front. I go 10/12 with 300/425 springs but whatever suits your springs obviously. Do that then see how it feels and you can adjust from there. Id be a bit miffed if a specialist told me I need new shocks to fix a handling issue on a car with adjustable suspension without even seeing the car.

Perhaps he's seen the problem many times before and doesn't need to see the car and anyway what was offered was a no risk money back deal if he couldn't see a significant improvement with the Nitrons fitted.

[PaulCP]

Paul what spring rates did you run on your blacks?

TBH I can't remember. Dan r has the car now and all of the receipts over the years. If you PM him I'm sure he'll give you the information

[PaulCP]

I'd try the geo changes before buying another set of coilovers. Many people use Quantums with no issues. Start with the the cheap things first.   I'm not saying one brand of coilover is better than another but new suspension is going to be ~six times the price of a geo set up. Most people wouldn't be able to split hairs between quantum's and nitron's on the road but they would notice a bad geo set up.

He's had a money back if not satisfied with Nitrons deal. Why wouldn't anyone go with it?

Agreed, provided they just fitted the Nitrons and did not adjust anything else, otherwise how would he know it the problem was 100% the Quantums

[fiveoclock]

 

 

I'd try the geo changes before buying another set of coilovers. Many people use Quantums with no issues. Start with the the cheap things first.   I'm not saying one brand of coilover is better than another but new suspension is going to be ~six times the price of a geo set up. Most people wouldn't be able to split hairs between quantum's and nitron's on the road but they would notice a bad geo set up.

He's had a money back if not satisfied with Nitrons deal. Why wouldn't anyone go with it?

Agreed, provided they just fitted the Nitrons and did not adjust anything else, otherwise how would he know it the problem was 100% the Quantums

 

They didn't say the problem was 100% the Quantums

Edited by fiveoclock, 21 March 2018 - 04:43 PM.