Ride Too Firm

PostPost by: William2 » Tue Jul 26, 2016 4:39 pm

I have rebuilt my suspension using Tony Thompson fast rear road springs that are 12" long and rated at 100LBs in conjunction with the shock absorbers that were already fitted to the car (not sure of the make) which are non adjustable. The front suspension and dampers are also from TTR. The wheels are 5" x 13" Minilites fitted with 155 standard tyres. I have adjusted the suspension platforms to give what looks like the correct ride height. At the rear this seems to mean turning the spring platforms so that there is about 1 1/2" of the bottom thread showing.
The problem I have is that the ride seems very firm compared to Elans I have had in the past with the standard wider rear springs fitted and non adjustable suspension and therefore less enjoyable to drive. I have assumed that if you use Minilite wheels you have to use the narrower diameter springs.
Is the problem possibly due to the rear shocks not giving a soft enough ride and is it likely that if I increase the ride height at the rear by turning the spring platforms clockwise further this will have the effect of making the ride even firmer? Has anyone else experienced a similar issue?
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PostPost by: bitsobrits » Wed Jul 27, 2016 12:09 am

100lb/in springs are much stiffer (in percent terms) from the standard road springs which (from memory) are something like 78lbs/in. So over 20%. Dampers can add to that stiffness depending on the brand and type. Also, just because there are no adjustment knobs doesn't mean the dampers aren't adjustable. At least some Koni's for the Elan are adjustable by undoing the top nut and rotating the piston rod with the piston rod full home. Not very convenient to be sure.

I run 95lb small rear springs with Koni's set full soft and the ride is firm but supple, and not harsh. My front dampers are TTR with 115lb springs, btw.

The standard Elan is a brilliant balance of comfort and handling IMHO, and when you start changing things, sometimes you end up other than where you intended.
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PostPost by: Mazzini » Wed Jul 27, 2016 10:38 am

I have TTR fast road suspension all round on my S2 and on my S3, both cars are set up the same

Both cars have had the suspension set up with lasers and corner weights.

The S2 is lighter and strangely it rides more smoothly, but the S3 rides more harshly. I wouldn't have really noticed till a friend took me out in his perfectly standard Sprint, then my day was ruined.

One thing I have noticed both cars handle much better in the wet, but that could just be down to tyres.

I think I will take set the TTR shocks to their minimum settings.
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PostPost by: rgh0 » Wed Jul 27, 2016 10:56 am

William2 wrote:I have rebuilt my suspension using Tony Thompson fast rear road springs that are 12" long and rated at 100LBs in conjunction with the shock absorbers that were already fitted to the car (not sure of the make) which are non adjustable. The front suspension and dampers are also from TTR. The wheels are 5" x 13" Minilites fitted with 155 standard tyres. I have adjusted the suspension platforms to give what looks like the correct ride height. At the rear this seems to mean turning the spring platforms so that there is about 1 1/2" of the bottom thread showing.
The problem I have is that the ride seems very firm compared to Elans I have had in the past with the standard wider rear springs fitted and non adjustable suspension and therefore less enjoyable to drive. I have assumed that if you use Minilite wheels you have to use the narrower diameter springs.
Is the problem possibly due to the rear shocks not giving a soft enough ride and is it likely that if I increase the ride height at the rear by turning the spring platforms clockwise further this will have the effect of making the ride even firmer? Has anyone else experienced a similar issue?


Assuming you have matching front springs of around 130 lb/in and shocks matched to those front and rear spring rates the ride will certainly be firmer than the standard setup. That is the outcome of seeking better handling with modern tyres in an Elan with what people sell as a "fast road" set up ( and the TTR fast road set up is pretty stiff) . You probably trade off some handling improvement and improve ride by softening the shocks you have to their softest setting. If the ride is still not to your liking you can get a better ride without trading off to much handling by going back to softer springs and a bigger front roll bar --- i assume you still have the standard front bar as most people dont address this with their "fast road" setup unfortunately and it is really the first thing you should change not the last

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PostPost by: MyLotus » Wed Jul 27, 2016 12:05 pm

Tire pressure may come into play. Should be 18/23 psi according to Shop Manual. Made a difference on my S4.

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PostPost by: rgh0 » Wed Jul 27, 2016 12:12 pm

MyLotus wrote:Tire pressure may come into play. Should be 18/23 psi according to Shop Manual. Made a difference on my S4.

Alain



Again it depends what your after in terms of ride versus handling balance. The original 18 /23 pressures gave a great ride and good handling with tyres of the era but are to low for best handling on modern tyres especially if you have a stiffer modern "fast road" setup. But if looking for best ride stick with the original spring rates and original tyre pressures but in doing so you give up some of the potential handling upside of more modern tyres.

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PostPost by: Apx » Wed Jul 27, 2016 12:52 pm

Rohan,
You mention the front anti roll bar for the fast road set up, what spec. would you recommend? i have the TTR set up and borrowed a "26R" roll bar, it didn't seem to make too much difference over my standard 48yr old one with the suspension on a medium setting.
Another stupid question possibly, but for road use do roll bars wear out or become "tired" and therefore need to be renewed?
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PostPost by: webbslinger » Thu Jul 28, 2016 1:07 am

APX,
If you are still following this, I think there's a fair chance that you have tbe old style Koni shocks. One answer you got described how to adjust them and Koni's web sight tells you how to do it as well. I just wanted to say that if you have them it's pretty easy adjusting them on the car, without removing them as most tell you to do, and it takes about 30 min per side.
To do it, first remove the retainer from the shaft at the top of the lotocone. Then jack up the car and let the suspension go to full droop. Measure the height of the spring perch and then back it all the way down to take pressure off of the spring. Push the shaft all the way down until rotating it you feel the adjusting detent. Clock wise is stiffer and there are 5 settings. I was getting bounce on full soft and am now at step 3 where it seems best to me. I have the same springs as you and Spax shocks in front with a 7/8" roll bar.
Reassembly is the reverse. The hardest part is extending the shaft back up through the lotocone far enough to get tbe nut back on. But if you use rubber jawed channel-locks (hose over them) to grip the shaft and have an assistant to hold it tight it is a snap.
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PostPost by: William2 » Thu Jul 28, 2016 11:10 am

Just to clarify the tyre situation, I am using standard 155 tyres all round with the original Elan profile. Judging by the replies so far I think I maybe need to try and find some rear springs with a rating nearer 80lbs as opposed to 100. Also some softer dampers. I did expect a harder ride with the TTR set up but not quite so much and I do not need fast road use or track handling qualities as these cars already have excellent handling if properly set up. A lot of the problems these days are more with the condition of the roads!!
I did look underneath the car to check the position of the wishbones and they are almost parallel with the ground.
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PostPost by: webbslinger » Tue Aug 09, 2016 11:50 pm

For anyone looking back at this I want to clarify that there aren't "5" actual detent settings on the Koni internally adjustable shock as my previous post seemed to imply. The shaft rotates about two and a half times and I use 180? for each "setting" so for me, 5 positions. I would assume some differences unit to unit so that combined with your taste probably means tying several settings and maybe something less than a whole 180? adjustment. Thanks. To me, bum info is worse than no info.
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PostPost by: david.g.chapman » Wed Aug 10, 2016 6:12 pm

Another stupid question possibly, but for road use do roll bars wear out or become "tired" and therefore need to be renewed?

Yes they can (so I've been told). I was having the eyes welded on my anti-roll bar a few years ago and the man doing it told me that a lot of anti-roll bars lose their springyness (sorry - technical term). He tested mine by clamping one end in a vice and leaning on the other end. It sprang back in a satisfying way and he pronounced it OK.

It yours is not so springy and takes a set if you do the same thing (no figures I am afraid) then the bar could be heated and re-tempered? Just ask your local blacksmith or engineering firm.

Dave Chapman.
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PostPost by: TroonSprint » Wed Aug 10, 2016 9:30 pm

Just for the record, because I went through this too, the factory spring rates for the Elan were 75 lb in front and 67 lb in rear. Yes, they really were that soft!
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PostPost by: nmauduit » Thu Aug 11, 2016 8:30 am

webbslinger wrote:APX,
I was getting bounce on full soft and am now at step 3 where it seems best to me. I have the same springs as you and Spax shocks in front with a 7/8" roll bar.


yes, it seems to me that once one has selected springs the damping level should follow rather closely, so that a move from resting position should be dampened without overshoot (i.e. stronger springs will need tougher damping settings for proper operation, as the suspension travel induced by a given disturbance will be less for damping by the time the car has returned to equilibrium position).
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PostPost by: alan.barker » Fri Aug 12, 2016 12:41 pm

If the ride is too firm return to original spec like my Sprint as was designed by Chapman :mrgreen: :mrgreen:
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PostPost by: greg40green » Sun Aug 14, 2016 11:10 am

My 'opinion' may cause a negative reaction but no intention to discredit or disrespect suppliers or owners is implied , I'm just stating my experiences re this subject.

I like many have invested huge amounts of time and money on trying to improve the handling of my ?lan's with only minimal success.
One of the big disappointments was when I changed to adjustable platforms front and rears using all new parts from a very reputable dealer.
Firstly the springs required continual readjustment to stop the Elan from going into negative droop this issue being made worse if / when having used the Elan with a passenger and any luggage.
I obtained another new set of 2.5 dia springs thinking I may have been unlucky but the new springs also require continued readjustment to stop the Elan going into negative droop.
I became so fed up with this problem and the fact that I was leaving parts of my very expensive exhaust system on the road I changed my tyres back from 60 profile Yokohama's to 70 profile Bridgestones with an instant improvement in the ride quality and ride height.
The issues with the 2.5 springs continue requiring constant readjustment to the point that the springs are becoming coil bound with little positive affect over bumps.
Becoming more and more frustrated I took the standard rear uprights , new standard springs , standard dampers ,standard size wheels and tyres ( 165x13x70 Bridgestones ) ,all new or refurbished parts and fitted them on my S4
The results were fantastic ( in my humble opinion ).
My personal advice is stay standard if running on public roads , don't use lower profile tyres ie 60's or lower as I have done ( Anyone want a set of nearly new 60 profile 13X175 YOKOHAMA'S ?100 for the 4 , absolute gift ! ) , don't go 2.5 adjustable rear platforms , don't use standard diameter rear springs but shorter length as are being offered by a supplier ( Why? ).
There are after market wheels out there that will fit the Elan without going 2.5 dia springs especially if using bolt on hubs ie I have 2 sets one 4.5'' knock on's alloys and one 5'' copy Minilites bolt on's. (I have a Sprint on knock on's)
Please note. I have used 'all ' the parts mentioned and many others to come to 'my' opinion.
The comments made are what I have experienced personally and are not the views and opinions of others experienced third or fourth hand.
Again ' in my humble opinion ' , Save your money and don't unintentionally wreck what is already a fantastic handling car by bolting / fitting inferior parts.
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