AVO & Protech shock absorbers & SJ Springs

[thewheelrestorer]

AVO Protech shock absorbers & SJ Springs

There are already off the shelf adjustable dampers by both AVO and Pro-Tech available for our cars and stiffer front springs are available from SJ sportscars. A number of people here have these fitted and I am not aware of any particular concerns

Happy new year to you all...........this thread is to discuss the perormance of the CURRENT replacement uprated shocks and springs available for this vehicle and discuss other options available for development through my contacts or anyone else's, I do not intend to be making money out of it, I enjoy understanding and modifying suspension for fun.


Anyone that has experiences and / or thoughts on how good or bad these products are (AVO, Protech,SJ) in comparison to the standard set-up please air your views:

Does anyone know why stiffer rear springs are not available from (SJ Sportcars) ?



As there has been lots of interest in people wanting better handling, one of my questions is the interpretation of this meaning (Handling)?

What exactly is happening to your drive to make you be requesting this ? (This is not personal - just a simple question)

[b]EG.
Have people had bad experiences where their car has lost control when pushed?
Have you been left standing by a Golf GTI around a corner and your quite rightly miffed!!
Are you fed up with the bangs and crashes that the car has when going over bumps etc.. ?
Does the bonnet aim for the sky under hard acceleration ? (Mine does!)
Does the bonnet point toward the floor under hard braking?
Have you pushed your car to a point where the grip finishes and you want more ?

Answers to all of these could be attributed to a lot of things which are NOT the car's fault: Tyres, Driver, worn parts (Shocks, springs, bushes, balljoint...etc) geometry etc..

The car has a reputation of handling well on the road in it's day and is still regarded as very good today, it's design when new was revolutionary, but technology has and does keep improving.

The car will have a limit of improvement due to it's design though, the new Lotus Evora should handle better than the previous Elise and
in five years time the benchmark could be different again.

Most upgrades will affect the ride quality, and if this is too important to sacrafice then stay close to the standard set up.

If however people don't mind the ride quality firmer because less body roll and a stiffer set up is their desire, it can be done, and you can do it in stages or smaller steps.

Changing the tyre profile is probably the first step because it does not change any other settings on the car.
You could also change the profile to lower the car, which will assist better handling (Lower centre of gravity). The downside is it will make your speedo reading inaccurate and also make the ride quality harder!
Then possibly the anti roll bars, whilst keeping the standard shocks and springs (

An improvement in the ride and body control will however not be done through one component, the components and characteristics that control these are:

The Wheel width, diameter and offset, weight and tyre pressures
The Tyre width, profile, compound, and condition.
The shock absorber
The coil Spring
The Anti (Sway) roll bars
The condition of the mounts, bushes and ball joints etc..
The cars natural static geometry (EG how all the angles of the 4 wheels are sitting naturally and in relation to each other)

Is there any demand from people to change some components to result in a similar if not better ride quality but also improve the body control?

It's the best of both worlds but not as stiff as a track day set-up this is being catered for by Bob with Bilstein and Eibach.

I look forward to hearing from those that want better handling but would like to know exactly what is not good enough ? what is the car doing or not doing ?

In the meantime I will be contacting my old employers KONI, Possibly some connections I have at AVO because I think their shocks they make now could be used with a spring pan that uses a 2.25ID coil and then 2 springs can be used and some comfort built in, also the bump and rebound valving could be changed.
The KW situation I am in contact with xiphias and if and when any fruition comes I will report forthwith, I may also contact a few high quality spring manufactures as a progressive spring could also work well (Tighter coils at the top, more open at the bottom) makes the compression softer to start with and then the resistance getting harder the higher the loading, this combined with an optimum rim size and tyre set-up and also different or adjustable anti rollbars (Yes I know this is an ongoing thread already) I believe this could acheive a very good ride and better body control (handling) than standard.

[Elanlover]

I have the stiffer front springs and Protech shocks from SJ. As for why only stiffer front spring are available I'll hazard a guess and say its because with all the power improvements that have been done to the Elan people were getting a lot more nose dive under hard braking. So, stiffer front springs were developed. That's just my guess however.

The Protechs seems fine to me but I'm not an expert in this area. You do have to crank them up to their max setting with the uprated front springs to get rid of the bouncing the front springs can induce due to their stiffness. But, my sense is that this entire setup has only marginally improved handling (maybe 20%?). Nothing to sneer at but I feel better can be had with something tuned better to the car instead of simply sticking over the counter aftermarket parts on. You get stiffer suspension and better cornering for sure. But I can't help shake the feeling that, while stiffer, it just doesn't have the same "truly integrated" feeling that the original gear has - if that description makes any sense

[dapinky]

I have the Protechs on the red one - they were fitted when i got the car, but one of the rear ones were leaking. The springs were original.

When i found the leaky shock (well, the MOT man actually found it). i needed replacements and there were no OE ones about at a reasonable cost - so i went for more Protechs. Whoever had 'set up' the car with them originally obviously hadn't got much of a clue - they were as hard as they could go and all spring heights were equal

I set it up with the shocks one click harder than a standard OE shock, dropped it by 1/2 " all round, then set up the corner weights as close as i could get them.

Then i drove it and didn't like it a lot (17" wheels, 205/40/17 Bridgestones) - not as much travel as i am used to on the Triumph (Track car, obviously NOT the rally monster ).

TWR has confirmed what i thought - the harsh ride was probably down to the Bridgestone tyres stiff side-walls - but i got round it by dropping the shocks 2 clicks, until i reverted to the 15" wheels, when they went back up 2 clicks to where i started.

i now run that car with Yokohama 008's on the front, Michelin Exalto on the rear, i click up on the shocks, 1/2" lower (ish), poly bushes all round (except the raft mountings).

Basically, it is tighter than standard (which is on the blue one), but not overly so now we're back to 15" wheels, but not as comfortable. You have to plan your route over speed humps, and avoid as many pot-holes as you can.


For the blue one - i want to keep the comfort as it is, so am left with looking at the options which come along to improve road-holding with regards to comfort.

I am currently waiting for these blokes to get back to work after the Christmas break to see what (if anything) they can do for me/us. I've had all sorts made by them in the past, and always been impressed - they have a lead time of about 4-5 weeks, but my springs usually arrive within 28 days of the phone call.

[thewheelrestorer]

elanlover

As for why only stiffer front spring are available I'll hazard a guess and say its because with all the power improvements that have been done to the Elan people were getting a lot more nose dive under hard braking.

Did I read somewhere that these front springs are the Fed spec front spring ? If this is the case then I guess SJ source them and offer them as stiffer than the standard se spring, in which case this is why a rear spring hasn't been developed because a front spring hasn't been developed either it's just been borrowed from a different model?

to get rid of the bouncing

Is the front or rear of the car bouncing ? If it's the front it may be that the uprated spring is too stiff for the front shocks when they are on their softest setting? And hence when you crank up the shock resistance it stops it?
Sometimes adjustable dampers don't seem to work very well at all on settings 0 or 1 but do something noticeable after 3 onwards. I spent a whole day tuning a set of Spax shocks on an Opel Manta 15 years ago, 14 positions of adjustment and a twisty fenland flat road as a test section. The best solution for this car at the end of the day was 3 front 10 rear.
If and when I have some adjustable shocks on the Elan I will be doing the same testing, it's invaluable.............you just need to find somewhere with no traffic or bobbies !!

my sense is that this entire setup has only marginally improved handling (maybe 20%?)You get stiffer suspension and better cornering for sure. .

That is as you say nothing to sneer at and a very good improvement percentage, and I'm thinking a good place to start for those that want "track day action"

But it just doesn't have the same "truly integrated" feeling that the original gear has - if that description makes any sense

This I think may just be the fact that the front spring (Stiffer) has changed the original front and rear balance. If you make a change on only one axle it's usually to cure or assist with a balance issue, EG Stiffen front springs increases Understeer and decreases Oversteer. If you had uprated rear springs fitted, you could probably back off the front shock setting a number or two and the balance should feel better. It's all fine tuning to your taste and driving really. Somebody could set up a car how they like, you drive it and think it was awful!!

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dapinky

Then i drove it and didn't like it a lot (17" wheels, 205/40/17 Bridgestones)TWR has confirmed what i thought - the harsh ride was probably down to the Bridgestone tyres stiff side-walls - but i got round it by dropping the shocks 2 clicks, until i reverted to the 15" wheels, when they went back up 2 clicks to where i started.

When you didn't like it, you mean the ride I think?.... but how was the handling? You had here what sometimes happens too many stiff components and a lower ride height:
Less tyre profile than stock 40 instead of 50, a wider rim 7"? as opposed to 6.5" stock, the protech stiffer (resistance than standard) dampers and a lower ride height (Less suspension travel) all this would cope must worst with the good old English non smooth roads, it would of been very good though as a track day car. And the proof was in the pudding when you changed back to the 15" Wheels as it made it so much better for you. I once put a set of 7"x 16" wheels with 205/45/16 on a Mark 1 rear engined MR2, had bespoke springs made 10mm drop front, 5mm rear, 10% uprated front, 15% rear on KYB gas shocks (Non Adjustable) and it would not handle nice at all........it was too stiff and wouldn't turn in to corners etc... I put the little 6" x 14" original wheels back on and the baby 185/60/14 tyres and it was a dream...............because the chassis could move again because the slimmer wheels and bigger tyre profile allowed it to do so.

so now we're back to 15" wheels, but not as comfortable. You have to plan your route over speed humps, and avoid as many pot-holes as you can.

As above the smaller wheels are better, and you're speed hump problem is the compromise of lowering the ride height!

Basically, it is tighter than standard

Again this is good feedback for the track days boys and girls

I am currently waiting for these blokes to get back to work after the Christmas break to see what (if anything) they can do for me/us

I think I know of these guys, there are a few besoke manufactures in the Sheffield area, depending on what shock absorber set up I can find I was intent on contacting them also, so please keep me posted on what you go for.

My car at the moment has a totally standard suspension but has a stiff wheel and tyre set up :
Rim width (7.5") x17"
Tyres low profile (40)
215mm wide (27 psi)

This gives the handling a sharpness and (Less roll) whilst "turning in" to corners much better than the 16" S2 wheels and also the 15" original wheel.
If I were to fit stiff shocks and springs I know with this wheel and tyre set up it would be awful on the road...............but on a track very good.

So I' plan to either retain the 17" wheel set up with a semi adjustable shock on low settings and I'm considering either dual rate springs (Progressive) or a 2 spring set up to keep the ride quality and movement (Same thing) and also not lower the car at all if I can help it.

Keep the feedback coming, as I suspected its the Ride comfort and lack of movement that is not feeling good, and this is the most common problem when people change the suspension hoping for better handling, which does actually happen but it doesn't feel good on public roads........they are not smooth enough.

[RayD]

I have a question or two...

When you approach a spring manufacturer for stiffer springs do you always use the original spec as a basis for the new ones?

Is the original spec always available, say for a Triumph Dolomite?

Or do you take the old ones for them to identify the inner and outer diameter, length and strength? So they can make shorter, stronger ones of the same size?

On adjustable shock absorbers does “one click” adjust both Bump and Rebound and in the same direction?

The reason I ask... I’m not sure why spring upgrades always result in stiffer springs as though they were always too soft to start with, as opposed to being too stiff or exactly right.

Even though it keeps getting repeated I’m not sure that springs get “weaker” with age, although I know they get shorter.

Having driven mine three and half thousand miles it’s never occurred to me it needs stiffer springs. Having said that it’s easy to imagine how some modern shock absorbers might improve it

Ray

[thewheelrestorer]

Hi Ray,

Happy new year,

When you approach a spring manufacturer for stiffer springs do you always use the original spec as a basis for the new ones?

Yes, If the intention is to produce a stronger rate (Poundage) spring the original off the car can be measured in size ID & OD and the coil wire diameter and the compression strength measured. This is done over a 1" distance EG: A 120Lbs per inch coil spring means once the coil is compressed and preloaded it is then compressed one inch and then a measurement is taken on this strength.

Is the original spec always available, say for a Triumph Dolomite?Or do you take the old ones for them to identify the inner and outer diameter, length and strength? So they can make shorter, stronger ones of the same size?

There are a couple of Spring manufacturers that have been around for many years and will have there own data and specs for older cars, but this information they should also have available for most cars from the 60's , 70's onwards, occasional if you want the spec of a 1959 Facel vega HK500 it may prove a bit trickier !

If a request for a shorter spring is the case then it really needs to be a higher (stiffer) rate than the original to avoid the suspension and car bottoming out. In this case the spring manufacturer will work out the free (open) length for this bespoke coil and also the poundage, they will need more info then like, vehicle weights to work out how much the spring will compress bearing in mind its shorter than before.

On adjustable shock absorbers does “one click” adjust both Bump and Rebound and in the same direction?

Yes, single adjustment adds resistance to a pre set ratio for the bump & rebound together
Some shocks have 2 individual adjusters, (1) for bump, (1) for rebound

’m not sure why spring upgrades always result in stiffer springs as though they were always too soft to start with, as opposed to being too stiff or exactly right.

upgraded is to always to go stiffer, you can get downgraded springs for a more comfortable ride, although these are much rarer to find!..............but I'm interested to make the Elan's ride even better than stock but also control the body better either with a reccomended wheel & Tyre package and stiffer roll bars, or a shock and spring set up which is orientated quite soft but gets harder the more loading it encounters (This can be done no question but will need some work, and testing to acheive it).

I’m not sure that springs get “weaker” with age, although I know they get shorter.

This one I'm never 100% convinced unyet I've had several cars where I change the standard springs for brand new ones and they are better! So I've come to the conclusion that they must weaken somehow? certainly if they rust badly the wire diameter is smaller and hence the strength less?

Having driven mine three and half thousand miles it’s never occurred to me it needs stiffer springs. Having said that it’s easy to imagine how some modern shock absorbers might improve it

Your car may not need stiffer springs, but maybe softer ones? in conjuction with a set of semi stiff shock absorbers and a stronger set of roll bars or adjustable ones could possibly acheive a nice ride and also good body control. Neither of them will be perfect, but if they are both good and well acceptable and better than standard this is surely the ultimate road package. The track set up is a different kettle of fish! As you know you can go stiffen the car up to the hilt for the track and have great fun, but it'll drive awful on the public highway!

[RayD]

Thank you Roger,

On reflection I should have said...I’m not sure why efforts to improve the suspension always result in stiffer springs as though they were always too soft to start with, as opposed to being too stiff or exactly right.

I’m not sure that springs get “weaker” with age, although I know they get shorter.

This one I'm never 100% convinced unyet I've had several cars where I change the standard springs for brand new ones and they are better! So I've come to the conclusion that they must weaken somehow? certainly if they rust badly the wire diameter is smaller and hence the strength less?

Springs will certainly “weaken” with age with regard to their capacity for snapping in two. As for the “poundage” change perhaps one of the suppliers will have some figures to support the answer as to whether a 120lb spring becomes 110lb one after 30,000 miles or if it becomes a 130lb one. (Figures plucked from the air)

Then there’s the springiness...there’s a good word.

Ray

[thewheelrestorer]

I’m not sure why efforts to improve the suspension always result in stiffer springs

Hi, because manufacturers generally make a production car as soft as they can without the car driving like a jelly ! This is so your average jo bloggs is not hacked off with the car manufacturer because the ride quality resemblies a donkey ride at Skegness!

So hence any replacements are always stiffer and / or shorter as this will guarentee better body control (Handling) but not comfort for the user who wants better handling....

The marketing will never read :

Fit "Trackfast" Sport Shock Absorbers for the Ultimate Handling Experience and Pi$$ Poor ride quality!**
**(goverment health warning these products will give you a disgusting ride quality)

[dapinky]

I have a question or two...

When you approach a spring manufacturer for stiffer springs do you always use the original spec as a basis for the new ones?

Is the original spec always available, say for a Triumph Dolomite?

Or do you take the old ones for them to identify the inner and outer diameter, length and strength? So they can make shorter, stronger ones of the same size?

On adjustable shock absorbers does “one click” adjust both Bump and Rebound and in the same direction?

Ray,

Happy New Year to you, mate!

I suspect you have a sneaking suspicion of the answers to these questions already, but have asked to get clarity for the forum

In my case, working with Coilsprings,co,uk, i have used three ways to get what i wanted.......

1) i have sent them a set of springs i wanted matched.
2) i have used the data they already had for the car
3) i was extremely fortunate to have a mate of a mate who preped all the works competion cars for BL in the 1970's - he still had his old jottings/drawings (not to mention a pair of unused Koni shocks - shortened Fiat/Ferrari units ) lying around and gave me the numbers the team used in the works competions vehicles.

Because of this, i had springs made to match the shocks i was given - but i fully accept that when the original calculations were made, the springs were probably sorted first, then the shocks matched to them. The shocks have a seperate bump/rebound adjustment on them, but all that is irrellevant to what TWR is trying to achieve here.

My own take is that i am looking for a 'cheap' way to get what i want for MY car........ i am looking at keeping the ride as compliant as possible, with a bit of extra stiffness thrown in........

I am hoping that by sticking with the Protech/AVO adjustable shocks, and getting a suitable 'variable rate' spring wound up for me, it will achieve all that i want. I have a set of OE shocks and springs, and some old Protech rear shocks (not front, though) which i am happy to send up to Sheffield so that they can have a play with them to get the spring rate/length matched.

I'm sure that if we could get the original specs from Lotus we would all have a better baseline to work from, but that has not been possible (despite everyones efforts) to date. The problem we all have is that we all have old units and none of us have any real idea how they compare now to when they were new, so we are all giving it 'best guestimate' based on the info we do have.

I believe that this is one benefit of an open forum, where as many people as can, will submit whatever info they can, to everyone's benefit......

....hopefully, that way we may end up with something which will do the job (but i'm no engineer, so don't necessarily follow me!)

[RayD]

And the same to you,

I suspect you have a sneaking suspicion of the answers to these questions already, but have asked to get clarity for the forum

It’s nice of you to say so Dave but you could still fill this hard drive up with the gaps in my understanding of cars.

Cheers

Ray

[thewheelrestorer]

I believe that this is one benefit of an open forum, where as many people as can, will submit whatever info they can, to everyone's benefit......

exactly............ the more the better, it's not what you know but who!!

I have a set of original front shocks which are brand new, these I also intended using to send to prospective manufacturers if need be,

I also think the spring seats can be changed or modified on the protech and AVO shocks and when used with a 2.25 ID progressive rate spring or a dual set up will provide more comfort and less harsness.

Coil spring know how and technology has come along way in 19 years since the Elan was designed.

Only time, and trial and error will tell, I've spent probably over £40,000 on cars in the last 18 years !! Scary I know, moddifying them etc...so I don't mind burning money with a proposed spring set up which may turn out to be no good!! It's only money and I'm skint anyway so I've nothing much to loose !!

[ektrolleyboy]

Erm...

Thewheelrestorer.

Your car is for sale on E-Bay!

???

[thewheelrestorer]

it is, and it isn't.............

I always live beyond my finances !! and everything is always for sale at all times if its the right price.

The reserve is set at a price similar to what a high class showroom in Surrey would be asking............if it goes it goes and then I may invest in more equipment for the business or buy another one cheap that needs some work............

I get really bored with driving sports cars on the road because after many years of circuit Racing I've reached such a level of personal exhileration? ,,,that I can't help but drive a car relatively hard on the road and this is not possible due to many problems....... too much traffic, camera's, licence, idiots, & obsticles like parked cars, skips etc..but the biggest problem is the road does not have an ambulance able to reach you within 1 minute if you go over the limit or are involved in an accident!!

Any sports road car with some power is too dangerous for me as I wil want to use it, the Elan is already becoming too risky as I keep pushing it and pushing it and unless you do something stupid the bitting point is very high, which is also why I've asked what exactly do people want more of? in the handling department...because there are only so many risks you can take on the public roads.

[ektrolleyboy]

But... Before, you were saying that you wanted more from the car because it didn't give you enough! Certainly in the suspension dept. And now you're saying the opposite?

I'm confused!

[theelanman]

I get really bored with driving sports cars on the road because after many years of circuit Racing I've reached such a level of personal exhileration?

in which case stick to track driving

I can't help but drive a car relatively hard on the road and this is not possible due to many problems....... too much traffic, camera's, licence, idiots, & obsticles like parked cars, skips etc..but the biggest problem is the road does not have an ambulance able to reach you within 1 minute if you go over the limit or are involved in an accident!!

doesnt sound very sensible....

Any sports road car with some power is too dangerous for me as I wil want to use it, the Elan is already becoming too risky as I keep pushing it and pushing it and unless you do something stupid the bitting point is very high, which is also why I've asked what exactly do people want more of? in the handling department...because there are only so many risks you can take on the public roads.

what kind of statement/view is that?.....I dont know any car from the smallest and cheapest to the biggest and most expensive that has this suspension youre talking of....a suspension that can cope with the power of the engine and the idiot behind the wheel.......think what youre after is a 2cv.......

[ektrolleyboy]

I'm sorry to nit pick and I don't mean to offend, but...

What do people want more of? Reads as if you think the car has everything and your reasons for the sale correspond...
Erm. Confused again!

I agree with your previous efforts and think the suspension has a long way to go to meet 2009 standards. But now there's back-track in your current statement! And I'm spotting a trend...

So what you're saying is... The Elan is for sale so you can go and buy yourself a 1.1 Peugeot 206 or the like?

[ailwyn]

So any chance of a thread where Wheelie & Trolley stay on topic?

[ektrolleyboy]

AILWYN...

What does it matter! Are you a school teacher! Are you going to mark our spelling next?

Chill-out, man!

[ailwyn]

AILWYN...

What does it matter! Are you a school teacher! Are you going to mark our spelling next?

When trying to keep a forum on-topic and relevant a lot! Can be if needs must! If you're that worried, buy a dictionary.

[ektrolleyboy]

Ailwyn.
It's just not important is it! There's no need to bitch all of the time! And believe me, you just do bitch!
I'm sure you're a nice guy, let's try and get on because it's tiresome. Okay?