AVO & Protech shock absorbers & SJ Springs

[thewheelrestorer]

Hi Jimbo,

Well done on your FTD in the wet, I guess the higher centre of gravity may of helped compared to stiff single seaters ? but nether the less it's a worthy acheivement.
Mr Minshaw these days has left Tweeks and joined Grand Prix racewear last I heard........

I did say an Average age of 60, this was purley a reference at some of the general content and critisims I've encountered since joining........with all due respect when I was 18 I thought 30 was old, now I'm 38 and I think 60 is old, and I'm sure when I get to 60 I'll be having a crack at some whipper snapper too!!!


I mentioned the word "Capri" once and somebody reply to me with rudeness,

I have also mentioned my work and racing experience to illustate to people I'm not from the furry dice stick on aerial brigade, this was also replied with a similar verve.

All of my ideas, data and solutions do have "have realistic input", I 'm not " talking down" to anyone, just doing the best I can to get blood out of a stone.



Getting back on thread.....................What do you suggest on the improvement handling thread ? obviously there are other avenue's being explored, I'm still amazed this hasn't been done before ? Why do you think people are only now thinking of better repalcement products like shocks and springs? Only on my first involved in a thread (KW) this was shot down in flames that it could not be improved? Which how could anyone moan at now with Bilstein and Eibach in the fray?


ektrolleyboy

I personally think we should leave these suspensions discusions alone from now on and merely thread on what exists and no longer theorise.

We could talk Protech, SJ front Springs and AVO shocks, but I thought people were after better than this? You only have to look at the Bilstein & Eibach list?

I think people do want more choice, it's just the mentality that needs to be better, that only Lotus could make an uprated shock and spring is not true.

Later............ gonna paint some wheels..... F355 Ferrari, Impreza, & M3, another late night coming up..........

[Monty]

I`ve only just got back tonight so i`ve not read the whole thread

I`ve got the Fed front springs on with the AVO`s but there useless as there the same height as the stocks which means you need to lower the Damper seat to keep the same ride height which means the springs are not under the correct load. If your going for stiffer springs then they need to be shorter.

This is only my opinion but i think SJ`s stiffer front springs are the Fed springs as he recommends them with adjustable dampers as they know it will increase the ride height on the stock dampers. The best way to find out is to ring them and see if they know the ratings of there front springs and i bet they don`t know

[thewheelrestorer]

Welcome back......Monty

I`ve got the Fed front springs on with the AVO`s but there useless as there the same height as the stocks which means you need to lower the Damper seat to keep the same ride height which means the springs are not under the correct load. If your going for stiffer springs then they need to be shorter.

It's late I'm still working and I probably have lungs full of solvent fumes.....so it's probably me....but something here doesn't add up???

Are you saying the SJ Springs are the same free length as the Se but becasue they are harder they don't compress as much? And to get the ride height as standard the lower spring has to be wound down? IS this then losing too much shock travel ? And hence if it was the same poundage but shorter you could gain more travel at a higher pan height?

SJ told me they are not Fed Springs but a spring they have made for them especially for the Protech Damper....

The spring poundage rate or preload shouldn't change because the lower pan is lower to get the height, it's just the lost piston travel that may be causing a problem?

Does the car bottom out ? and / or feel very harsh and too stiff to "turn in" ?

[Sy V]

The SJ uprated (stiffer but same length) front springs we're made in consultation with Philbo and/or Sooty (members since 2003), to counter nose-dive on braking (IIRC), and were to be used with the GAZ adjustable shocks that SJ stocked prior to swapping to AVOs following a number of leakages/failures (one of my rears included).

[Philbo]

I'll chime in because I was responsible for the original uprated springs.

Basically, from around 2001, I began modifying my Elan for track work. After a couple of track days, I really got to notice the excessive body roll, particularly at the front. I called SJ Sportscars and they had some Gaz dampers but no springs. I basically commissioned them to get some new springs manufactured to match the OEM ones in all but stiffness. We debated how much stiffer to make them, in the end I took a wild stab in the dark and asked for 15% stiffer than standard, as I wanted a significant difference from standard so that we would know which way to go (stiffer or softer) in case they didn't work out.

At the time, I was fitting a new turbo and trying to get it fuelled correctly using a Haltech and a custom map and this took a LOOONG time (years), so it was a while before I got to drive the car with the new springs and Gaz dampers. By this time, SJ had begun to offer the uprated springs as a standard item with the Gaz dampers.

So, in answer to the questions:

1. The SJ springs are rated at 15% stiffer than OEM UK because that is what I asked for. They are not based on Fed spec ones.

2. There are no rear ones because I didn't ask for any! In my track work I felt that the front was moving more than the rear, bearing in mind the weight bias being over the front wheels I felt that as a starting point making the fronts stiffer would be the place to go.

3. Are they correct? I don't know, I haven't driven the Elan on full tap on a track since adding them, so I don't know how they really affected the car.

My goals were not to "modify" the suspension in any way other than reducing body roll. In terms of changing the handling characteristics of the Elan, I'm not sure that that is really desirable, but being a complete noob at this kind of stuff my expectation would be that it would involve an awful lot of trial and error with an unknown outcome.

Overall, I spent a LOT of money on the Elan to try and make it into a track tool (I organised the first group buy of Quaife ATB diffs) as well as complete suspension, engine and drivetrain overhauls. To be honest, I came to the conclusion that without stripping the car out and making some substantial changes, it was never going to be as much fun to drive on track as something that was originally designed for the job, so I ended up with a Radical for that and kept the Elan as a road car.

[Monty]

I`m not that well clued up on suspension etc but when i fitted the Fed springs the car was very bouncy so had to turn the damper right up to counter act this, which means you can feel every bloody bump and i believe this has caused me more understeer on track hence why i`ve been intouch with Bob along time ago to look in to a better set up.

To me
a) just fitting stiffer front springs will mess up the balance, all 4 corners need to be done
b) stiffer springs need to be lower to keep the same ride height and keep the spring under the correct preload on the damper

[JIMBO]

Getting back on thread.....................What do you suggest on the improvement handling thread ? obviously there are other avenue's being explored, I'm still amazed this hasn't been done before ? Why do you think people are only now thinking of better repalcement products like shocks and springs? Only on my first involved in a thread (KW) this was shot down in flames that it could not be improved? Which how could anyone moan at now with Bilstein and Eibach in the fray?

I believe the reason for "suspension and handling" coming under such scrutiny is because so many of our cars have been
uprated and improved in so many other critical areas (Brakes, Power Output, lsd? etc) that it's 20+ old years technology,
is showing its age (like me). This, coupled with the handling improvements in more modern cars are causing some people
to look for possible improvements, and others to defend what they believe to be a great design. And so it was 20years ago.

How to improve it? not being blinkered, and not by squabling amongst ourselves.

We, no matter how good we are, are not in a position (unless you can tell me different) to carry out "back to back" testing under controlled conditions with a range of variable parts, tested by a profesional "test"driver (different from a race driver)

Good solutions cost money!! Has anyone asked Lotus for their input? (they have all of the required facilities) . Yes I know
they are in business to make money, but some of them are still car enthusiast's and might lend a sympathetic ear. It could even be a project for an apprentice ? with guidance !!

My own personal thoughts are way off the wall !! Conventional sring and damper changes will allways be a compromise -
too stiff, too soft, too much camber change,too much bump steer, too much/too little travel etc etc etc.
WHAT ABOUT AIR SUSPENSION ?
Jim

[ailwyn]

I realise that the Elan is a road/comfort setup and that some want a more track based setup, but I read with interest all the comparisons that are made between the Elan and a modern car, or suspension developments over the last 20 years....

How much improvement has actually gone into the springs/dampers/ARBs over 20 years? Are they that much better? Or is the improved handling of more modern cars (as perceived by the average drivers on internet forums) more attributable to the little black boxes: traction control, active diffs, ABS, EBD and a multitude of other 3 letter abbreviations?

If it is down to the bits and bytes rather than springs and dampers are we not comparing apples to oranges?

[Elanlover]

I think that's a great point Ailwyn. I too have wondered just how much "better" modern suspensions are over the Elan's system. And, most importantly, it depends on how one defines "better". Even with all the electronic systems in cars today I don't think they "handle" better than the Elan's non-electronic suspension does. Sure, they control slip, etc. mostly through reducing indvidual wheel power and the like but is that really better "handling" as we would describe it?

I don't think so.

I think just about everyone here has defined "better handling" (as far as our Elan goes anyway) as less body roll, less nose dive, flatter in corners and the like. Isn't that pretty much all controlled by springs, shocks and the suspension design (wishbone, double wishbone, etc.)? If so, I would bet plenty that no one here is going to claim they can build a better suspension design (wishbones, etc.) than Lotus did for this car. So doesn't that leave us with springs and shocks? And, as Ailwyn has said, just how much better are they today over 20 years ago? I'm not talking about stiffer springs as an example. That's not "better" - just different. Lotus could have done that themselves at the time if they'd wanted to.

So, for all the people who have claimed we can make the suspension better because the Elan is 20 years old I say bah! (which is how I've always felt when hearing that claim). I think we can make it different. And, depending on who you are and what you want, that may be "better" or not.



(of course I could just be talking out of my a$$................again )

[MattDon]

i think you both raised valid points, but i think you could improve the damper and spring setup, the elan is a production car and as such is built to a budget, its just a matter of how much you want to/can spend. i was talking to a motorsport engineer last week, and he had some very interesting ideas, the frightening bit was when he mentioned £5000 per corner for realy good suspention

[thewheelrestorer]

Blimey £5000 per corner is way off expensive and off the mark for what can be achieved here, I have no doubt....Ithis must be Racing use ? circuit and / or Rally cars...Proflex, or Ohlins or Penske etc...


Jimbo:

Good solutions cost money!! Has anyone asked Lotus for their input? (they have all of the required facilities)

I Don't know about the past? of course on the other Bilstein & Eibach thread Bob has mentioned an interest to contact them.

Conventional spring and damper changes will allways be a compromise

Yes and no,......stiff will be taughter handling (Less roll etc.. more feel) but crashy ride, and soft or standard suspension, wheel size, & profile etc.. much nicer ride quality, but inbetween with some differences using better damper & spring technologies (Dual & Progressive) +roll bars ? will add better body control and at least retain the same comfort.

We, no matter how good we are, are not in a position (unless you can tell me different) to carry out "back to back" testing under controlled conditions with a range of variable parts, tested by a profesional "test"driver (different from a race driver)

We don't need to, we're not looking to optimise two tenths of a second around a racetrack by rigerously testing and testing, it's a road car and a million miles from any racer...so we can get the latest manufactures (Eibach, Bilstein, Koni, KW, etc..) to use there proven formulas on road values, (Damper bump and rebound settings with the latest load sensing valves etc... and the latest spring technology to improve both attributes (Ride & Body Control)

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Monty

i believe this has caused me more understeer on track

Yes, I agree stiffen one axle only will decrease traction quicker than the other axle if this has not been changed, which is why all the front wheel drive racers spend a lot of time getting a set up for the rear of the car to oversteer, so just when the front starts to understeer slightly the rear oversteers and then you have a 4 wheel drift (Nice and controllable and with good feel through the steering wheel) but the beauty is the front is "turning in". There's nothinmg worst than screeching front tyres and the car ploughing on ahead towards the scenery!

To me
a) just fitting stiffer front springs will mess up the balance, all 4 corners need to be done

Yes exactly, the rear springs need doing desperatley and also the rollbar, but it needs to be thought out so that any changes are either minor or major. Sometimes a small change isn't enough to show up any change in balance and a bigger change will show itself up much more clearly. Like whack up the rear tyre pressures by 10psi!! 36! then you' should have some oversteer

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philbo

The SJ springs are rated at 15% stiffer than OEM UK because that is what I asked for. They are not based on Fed spec ones.

Ok, thanks for the info.

In my track work I felt that the front was moving more than the rear

The dive under braking?.............Or the body roll?

[quoteAfter a couple of track days, I really got to notice the excessive body roll, particularly at the front. ][/quote]
This may of answered the above question?

Are they correct? I don't know, I haven't driven the Elan on full tap on a track since adding them, so I don't know how they really affected the car.

Ahhh that would of been an interesting acid test then, although Monty has done this with negative comments and a too understeery balance.......

Sy v also mentioned........

to counter nose-dive on braking

This can be reduced possiby by the rear damping on rebound.

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ailwyn

How much improvement has actually gone into the springs/dampers/ARBs over 20 years? Are they that much better?

Oh my God !! Loads..........Since 1989 Heaps.......

Or is the improved handling of more modern cars (as perceived by the average drivers on internet forums) more attributable to the little black boxes: traction control, active diffs, ABS, EBD and a multitude of other 3 letter abbreviations?

Yes and No, new Mass produced cars these days are build with stiffer structures and chassis than 20 twenty years ago, the driver aids will of course help Jo bloggs if he fancies punching the throttle in his 300bhp M3 on a slippery diesel roundabout! In a previous 1989 320 he would of been looking through the side windows

But the designs for better performance have all improved just like everything else from 20 years ago (Mobile phones ! Microwaves! TV's etc...)

Look at all these raw Bike Engined Super stiff track day cars like radical's, X-Bow, Ariel Atom etc....they don't have driver aids yet the handling on these lightweights is very direct stiff and race handling like ...due also the damping and springs!


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Elanlover

And, most importantly, it depends on how one defines "better". Even with all the electronic systems in cars today I don't think they "handle" better than the Elan's non-electronic suspension does. Sure, they control slip, etc. mostly through reducing indvidual wheel power and the like but is that really better "handling" as we would describe it?
...I don't think so....

A new 2008 sportscar, or even some hot hatch's with no electronic aids corner as well and some better than the Elan, it's evolution of automotive designs.......

I think just about everyone here has defined "better handling" (as far as our Elan goes anyway) as less body roll, less nose dive, flatter in corners and the like. Isn't that pretty much all controlled by springs, shocks and the suspension design

Yes, obviously the design is not going to be redesigned that's not realistic, but the 1 component that can be changed is the coil over assembly, and a modern damper and spring will still go up and down like the original but it's control of going up and down will be better..........better for the car 's body to not pitch and roll and also better compliance of the underlations (Ride quality)

I'm not talking about stiffer springs as an example. That's not "better" - just different. Lotus could have done that themselves at the time if they'd wanted to.

Stiffer springs would be different, but if somebody here wants a stiffer car for mostly track use it will be better than a stock car around a track, in other words if both cars were given a lap by the Stig the uprated damper and spring car would be faster..no question. Lotus would not be wanting the road car to be too stiff, the word would get out, people would of hated driving it and they would not of sold as many as they did.

So, for all the people who have claimed we can make the suspension better because the Elan is 20 years old I say bah! (which is how I've always felt when hearing that claim). I think we can make it different. And, depending on who you are and what you want, that may be "better" or not.

It can be made better for a tracky, an occasional tracky, and a general road user going for a 2 hour drive to the beach.

KW produce coil over assemblies for some fairly high performance machinery, when a Porche 911 Gt is fitted with their speciality it's better than the standard set up from the boys at stuggart, why ?........because they are building production cars, very high quality ones for the masses, and not everybody wants to change their car, they like it the way it is, because they are not interested in better (Grip) handling and they also may not be convinced it can be any better for them.......which is fair enough everybody desires different things.

For those that are interested.......Keep the questions, solutions and feedback coming.

[GeoffSmith]

Has anyone asked Lotus for their input?

For the ~£800 Esprit Eibach/Bilstein upgrade, Lotus required commitment of ~75 people from LEF to proceed (Lotus had to stump up ~£5000 on the test cars to satisfy their insurers, so someone got a real bargain service). Some work has already being done by the suppliers (gratis) and we know the Lotus contact details if we think a similar arrangement could/should be made for the Elan.

[thewheelrestorer]

geoffsmith,

For the ~£800 Esprit Eibach/Bilstein upgrade, Lotus required commitment of ~75 people

Maybe this needs to go on the other Bilstein & eibach thread where Bob also metioned getting Lotus involved? I think this list is up to about 13?

Talking of handling, and drivin................... today I drove a customers car as below:


Engine Size 4799 cc
Cylinders 8
0-60 mph 5.2 s
Power Output 361 bhp
Valves 32
Torque 490 Nm 361 lb-ft
Top Speed 155 mph
Weight 1670kg

I didn't like the feel of it at all, but it was a comfortable ride, but it had a lack of communication through the steering wheel, it almost felt like driving on ice!!

A 4.8 V8 and 0-60 in 5.2 is not slow and the torque at 490nm is a fair lick, it was sport automatic box though and was very punchy pulling out of T juctions
to the point where the inside wheel would wheelspin, it felt big and lardy which at 1670kg is quite heavy but not a bad feat for a 5 litre v8 ! but I didn't feel like it could be chucked about!

Anyone guess what it is?













6 series beemer, 650i.
Later..........

[JIMBO]

6 series beemer, 650i.

Should have tried my 535 M Sport !
It doesn't get much better.
Jimbo

[thewheelrestorer]

Should have tried my 535 M Sport !
It doesn't get much better.

Hmmmm....... I beg to differ..........as I said I didn't like really like the 6 series but a 535 MS wouldn't be for me either....too heavy and lardy to throw around!

Is it the Diesel or Petrol model ? Pre 1996 -03 ? and Isn't this the little baby 3.5 litre that was Probably £35K new and now worth 5K ?

If it is this bird, it also weighs a hefty 1685kg which is a tad heavier than the 4.8 Litre 6 series and more importantly...100 bhp less & 150 nm less torque.......

I think if you had the M5 V10............this would warrant your opinion that "It doesn't get much better"

I'm sure it does what you want it for, everybody has there own tastes etc.....this is not a dig.

[JIMBO]

Should have tried my 535 M Sport !
It doesn't get much better.

Hmmmm....... I beg to differ..........as I said I didn't like really like the 6 series but a 535 MS wouldn't be for me either....too heavy and lardy to throw around!

Is it the Diesel or Petrol model ? Pre 1996 -03 ? and Isn't this the little baby 3.5 litre that was Probably £35K new and now worth 5K ?

If it is this bird, it also weighs a hefty 1685kg which is a tad heavier than the 4.8 Litre 6 series and more importantly...100 bhp less & 150 nm less torque.......

I think if you had the M5 V10............this would warrant your opinion that "It doesn't get much better"

I'm sure it does what you want it for, everybody has there own tastes etc.....this is not a dig.

As you say, everyone has their own opinion, but this is a 2006 diesel with Alpina suspension mods and chipped to 330bhp,
with even more "torque" than you
This is also OFF TOPIC. (or is it ? )Alpina suspension mods)
Regards
Jim

[Specky]

with even more "torque" than you

TTFN

[thewheelrestorer]

Okey Dokes,...........I did wonder and mention was it the oil burner engine

I guess it's on a slush box too ? (Automatic) with all that torque...
BMW used to use the model numbers for the engine size etc.......but the technical info I have on this model seems to say it's a 2993cc but badged 535?
With the remap and increases I bet it's a right cruise ship,........just the kind of vehicle I'd take for a drive through europe.....

Anyway...............this car is only aged 3 , it can't have more talk than me I've been on the planet since 1970 !!

This is also OFF TOPIC. (or is it ? )

.....................oops


AVO
I hope to be contacting AVO next week, in regard to the shock set they currently produce and the possibility of producing some modified units for the track day boys, and also the feasability of using a 2.25ID Spring pan and then universal race coil springs can be used. This will allow anyone to choose how stiff they want it for the track, and / or both etc...

Also KONI produce a patented technology called FSD used on Mr. Hamiltons F1 Mclaren to good effect last year, this has excellent ride quality & taught body control properties, I would imagine if Lotus wanted 75 people to warrant the Esprit project, Koni may want more and this could be a problem getting the numbers, but I'll make some enquiries soon, I've just been flat chat all week fixing bent and cracked round aluminium things............

So some modified versions of a current available product (AVO) will certainly have more chance of being made and less expensive.........

later..........

[thewheelrestorer]

AVO Update..............

I have some info from them on the shock they currently produce that:

The lower spring pan which currently is designed to accept the standard stock spring, can be exchanged for a different version which will accept a 2.25 ID Race coil.

Don't get confused people when I say race coil, for those that don't know race coils are a range of springs which all have an inside diamter in this case of 2.25",
but more importantly are available in different free (Unsprung) lengths and more importantly still different spring rates usually in pounds.

So race doesn't mean it's for race use, beacuse you / we can choose whatever spring rate (Stiff or soft) we want from a vast range for different applications.

For example you could actually use a poundage exactly the same as the currect car, or go a bit softer if you prefer a better ride, but we have to be careful as softer may not work too well with the standard replacement AVO shock as it's bump and rebound ratio is 2:1 and I don't know if the standard Lotus shock is the same as this or different yet!.

But................before we continue the current top spring mount will not accept a 2.25ID Spring............
But..........One can be made and this I can do with a local machine shop.

I've got 2 rear standard SE strut and spring assemblies and also 2 front SE shocks but not the springs or top mounts yet!!!

The next plan is to complete the above and then be in a position to send (1) front and (1) rear strut and spring assembly inc top mounts to AVO and get them to
find out the spring spec and damping settings.

Then I can ask them what options are available based on the current units and at what cost.

If we feel the current AVO product is a tad too stiff, then maybe a new unit is possible inbetween the Lotus and current one, in other words it will be slightly better than stock and also better ride quality than the current avo if that makes sense.

Then for the tracky boys, we can get them to possibly make an even stiffer shock and advise stiffer spring rates front and rear etc...

To be continued........

[abmunro]

This sounds like good progress.

I am watching all the current suspension/spring/shock threads as I hope to improve my cars handling.

I think most of us are in the same boat.

We will watch and wait to hear feedback from any developments and chose between them.

But in the end it will all come down to VALUE FOR MONEY. not just the cheapest.

Good luck with the developments and thanks for your work..

Tony

Ps my Jo Bloggs machine has 343 BHP and the Electronics work instantly. The back end of mine has tried to step out a couple of times but I have never lost it.