Shorter & uprated Springs

[Monty]

I`ve started this thread as i`m not happy with my suspension set up and i think this is the next step to take and maybe with a stiffer rear anti rollbar too (which i`ll start a new thread on) There has been talks in the past and Da-pinky knows off a company who can do the springs but we need to know the stock ratings, if there`s enough interest what about is all chipping in to buy a new front & rear spring so they can be tested?

A while ago there was a similar thread (can't remember when or who ) - but the end result was that we can get any coil spring made, in any rate we want, at any length and diameter.

It will cost about £40 a corner (IIRC) and i can vouch fo rthe company involved as i have used them alot in the past.

The only/biggest problem is knowing what you want!

Lotus will NOT divulge the standard spring specs (they were asked the question), so the only way i can think of is to get a NEW/unused spring and have it tested to ascertain the spring rate, that will then give a starting point to work from.

The guy i have used knows his stuff and with the accurate weights of the car, can help to develop a spring which will give the ride height you want, with the rate as appropriate.

[Monty]

Another quote

I have just been talking to Andy Waters about the suspension on the Elan as he has just driven it today to test it after fitting the new peco.
Andy races his exige in the elise trophy and has had many years preparing and racing all sorts of cars.
I also have a 111s elise which Andy has uprated with his racecar settings and I can assure you not many things will keep up with it through the corners.
His view was that, amongst other things, he would have stiffer springs made up and alter the castor to give more feel to the steering. He has recently done similar things to a MR2 that races and is now running rings round the rest of the field. He has offered to use my car as a testbed with a view to offering a setup to anyone else who may be interested.
What I need is a front and rear spring so that he has something to work on. I would appreciate it if anyone could loan/sell me one of each. I would obviously sort out the carriage charges.
If there is any interest in this project I will keep you all informed.
Chris

[Nige]

Monty again (as per the roll bar thread) I'm with you on this but have no specialist knowledge, although I've read a lot of stuff and think I understand the basics of the theory. I was planning on getting into discussions with Pro-Tech to see if they could do a double rather than single adjustable damper for the Elan but as I'm currently not in a position to buy given recent expense I don't want top take up their time at the moment, maybe in a few months time I'll approach them. I think the other things we need to consider when looking at springs and dampers is the amount of unsprung weight we are seeking to control. We all have different brake, wheel and tyre combinations and the combined weight of these is a factor we need to incorportate to do this properly.

[bobbrown]

Probably the best people to talk to about springs and spring rates etc are Eibach, I have used them in the past when building a custom rally car and did not have any information regards to spring rates etc just the rough free length required.
I gave them the corner weights of the car and they cam back with a set of springs, which proved to be just about correct.
Did have one slight advantage over the stock system in as mich as they were on full adjustable spring platforms etc
They will not be a cheap option as they are a quality product.
They can probably advise on anti roll bar rates as well but not sure on this one as Gartrac made up these on this rally car.

Bob

[chrishewett]

I have just had another chat with Andy Waters about the uprated suspension project.
I have some standard springs and shocks coming for him to assess. He will then have some stiffer springs made up along with different length inserts. With a bit of trial and error we hope to produce something that will be of use for trackdays but not too uncomfortable for the road.
He doesn't think that anti rollbars are the way to go as they tend to lift the inside wheel on the bends. He tends to disconnect it on his race car.
He is also going to produce a stiffener bar for the rear turrets which will be available off the shelf.
He is hoping to get to Hethel on the 14th so will be available to talk this through with any of you guys that are there.
If anyone wants to run any ideas past him he is at :- AW Tracksport, The Workshop, Lincoln road, Horncastle, Lincs 01507 522242
Chris

[Monty]

Nice work Chris

For me i`m thinking of 10 to 15% stiffer springs but i want the car to sit 1" lower than stock so the spring need to be shorter accordingly. I`m interested but I don`t know if Da-Pinky is going to look in to this as he`s got contacts and there at a reasonable price.

So come on Dave give us your input

[Monty]

Nice work Chris

For me i`m thinking of 10 to 15% stiffer springs but i want the car to sit 1" lower than stock so the spring need to be shorter accordingly. I`m interested but I don`t know if Da-Pinky is going to look in to this as he`s got contacts and there at a reasonable price.

So come on Dave give us your input

I bet if we can work out the ratings and dimensions maybe possible to get them off the shelf

[abmunro]

I'm definitely interested in better suspension set up...

[bobbrown]

Nice work Chris

For me i`m thinking of 10 to 15% stiffer springs but i want the car to sit 1" lower than stock so the spring need to be shorter accordingly. I`m interested but I don`t know if Da-Pinky is going to look in to this as he`s got contacts and there at a reasonable price.

So come on Dave give us your input

I have spoken to Eibach and they have said they will work out what is required e.g. spring rates. lengths etc depending on the ride height etc required
Now as per usual with all this some information is required by them
Sping free length
Spring internal diameter
now two tricky ones spring rate + corner weights of the car e.g. the weight on each wheel and no you can not take the front axle weight and divide by 2.
They can work out the spring rates from a set of springs but would require a pair and are based in Leicester.

If anyone has this sort of information I can forward it on to them

They do all the springs for Lotus and work out what rates etc they need so I feel these are going to be the best people to talk to.

Bob

[ailwyn]

They do all the springs for Lotus

So don't they know the details?

[dapinky]

Monty - as requested you can have my input

I dont want any springs, so have limited interest in the project ....





.......That said......

I have already agreed with Chris for him to have a set of shocks and springs - they will be going via Hethel!

I don't know where he is taking them, or if it is the same people as Bob is talking to.

I know Eibach only by reputation (a good one!), but have never used them.

The company i have used is http://www.coilsprings.co.uk/ and can vouch for them - albeit that i'm sure the others would do a good job as well.

Coilsprings claim to have the OE specs for Lotus cars, so might be a good starting point???

[bobbrown]

So don't they know the details?

May be I should clarify "they do all the springs for Lotus now" its been comming on for 20years since the development of M100 so I doubt very much they did the springs for the M100 but it may be the case they have the right contacts within Lotus to find out

Bob

[chrishewett]

To clarify:
Andy Waters is going to set my car up as an experiment with his own spec springs which he will have made for him by his usual source. He will also have different inserts made up to suit. He will use his years of experience as a racing driver and preparer of various racing cars to set the car up. He has full laser geometry and corner weight equipment adequate to set up a race winning car. I believe that this is a great chance to use his knowledge to improve my car. I am happy to use my car as a guinea pig in this as Andy has already set up the suspension on my elise 111s and my brothers TVR cerbera with great results. If anyone else can benefit from this project I will be happy for them and for Andy if he gains business from the project.
However, if you guys have a prefered source of experience and supply I will gladly keep this project to myself. I am not trying to persuade anyone to use my prefered motorsport engineers over their own.
Thanks to Dave for his offer of springs which Andy will need in this project.
Chris

[bobbrown]

Do I detect an issue here if so it was not intended

I have had experience in the past of people in the past who say they can do something but when you look at the results they have been rubbish.
Now I am NOT saying this is the case in this instance, but it is better to have a second opinion if nothing else.
If one says the springs should be x long and 400lb and the other says y long and 800lb then someone is wrong.
I was interested to see if the results were going to be the same and is more information a bad thing.
Eibach do the springs and setups for some of the big boys including Audi (DTM) Focus WRC, BTCC cars and lots of others so they do have the know how.

The only true way to get the best setup is to test and this can take a lot of time and if you have to pay someone a lot of money.
It is not just springs and dampers but a lot of other things that effect the handling from ride height, to caster and camber angles, all of which take a lot of time to get right and then what you have may be good in the dry but is a disaster in the wet.

[Monty]

This is a great discussion, hence why i started this thread and everyones views are welcomed.

I`m not after a race car cause thats going to cost ££££££££ i`ll be happy with just reduce the amount of roll so the car is more flat through the corners. Since nobody knows the rating and we don`t have a new springs to have tested i think lets see where Chris gets with Andy Walker. I`m in no rush and this would be a project i`ll start next year, so this a thread to watch

Chris,
When Andy starts on the set up can you get as much information as the project goes along?
eg
The stock spring ratings/diemensions
New spring ratings/dimensions
Dampers & setting
Geo setup etc

Cheers
Jay

[chrishewett]

Jay,
All information will be available from me or direct from Andy ( I recommend the latter!).
I am sure that there are many large companies that could do this job well but I am sure that like me most of you guys have less than unlimited funds. This project is an attempt to achieve results without a huge outlay. Andy understands this as he has funded his career without huge backing. I can't afford the fees eibach, lotus & co charge so I will stick to my approach.
As I said, anyone interested in following this keep in touch.
Chris

[bobbrown]

FYI

Eibach are not charging for their expert opinion, they make their money selling product and in their book it is no good selling springs if they are wrong for the application as it does not do their business any good.
OK they are not the cheapest kit but they are one of the best, it is quality and as they say you "pay for what you get".

[surfboardfiller]

I have spoken to Eibach and they have said they will work out what is required e.g. spring rates. lengths etc depending on the ride height etc required
Now as per usual with all this some information is required by them
Sping free length
Spring internal diameter
now two tricky ones spring rate + corner weights of the car e.g. the weight on each wheel and no you can not take the front axle weight and divide by 2.
They can work out the spring rates from a set of springs but would require a pair and are based in Leicester.

If anyone has this sort of information I can forward it on to them

They do all the springs for Lotus and work out what rates etc they need so I feel these are going to be the best people to talk to.

Bob

Sounds like a great idea Bob. I think I have a set in the garage I'll dig out for you.

[Monty]

Nice one Phil

Have a couple off options ie with Bob and Chris will benefit us members

[Candles]

Chris,

I'm in Lincs as well and since rebuilding various bits of my car, have been looking for someone to set up the geometry and corner weights. I'm guessing your contact Andy could do this? Could you recommend him to me with contact details?

Out of interest, I've gone for: Protech dampers, new rear springs & 20% uprated front springs. I've found it very hard to set up the car so it feels right as I've just been using a steel ruler to measure spring-seat height and a laser pointer for tracking. I've never adjusted the camber. With the protechs, I found that the factory damping knob position doesn't go hard enough to cope with the 20% uprated springs. The ride is quite good now but firm.

Candles.