Suffolk Ride height

[MalcolmB]

I am confused by what I have been told by Suffolk. I finished my car in July 2017 and the front suspension is way too hard and the rear is too soft & grounds!!
Suffolk tell me the spring rate is 275 lb/in on the front and I see from the Forum 4jagsjohn has tried 225 lb/in fronts. This seems a big change softer and I would be very grateful to pick any brains on others experiences.
Suffolk suggest ride height should be c. 42cm from spinner centre to underside of wing. I am going to visit a weighbridge soon and get accurate weights for car and front/rear distribution and work on the front suspension first.
I do not like the preload (due to the ride height adjustment) that Suffolk suggest on the springs seating and I think the harshness of the front suspension may also have a bearing on the accelerated bush wear and failure?
I am minded to try some 250lb springs and possibly get my current springs measured so I know what they actually are. Faulkner springs near Chichester and not far and a major spring manufacturer.
Longer travel and softer rate seem to me to be a good combo. I can recall changing from a old Morgan +4 to a Lotus 7 in my youth and marvelling at the improvement if ride!!

Anyone else tried anything different??

Cheers
Malcolm

[NATONEIL]

Malcolm
I share your concerns and have had similar problems. I am tied up today, but will post a detailed response in the next few days.

[NATONEIL]

Hello Malcolm. I have not been on the forum for some time, for which some will be truly thankful. Reading your post above and in the "where is SS thread" you are asking many of the same questions I asked when I finished my car. I have had my SS100 on the road for 5 years and have covered nearly 27000 miles. With regards to ride height I think that the ride height, as designed is a little low front and rear. To get some improvement I raised the front by winding up the ride height adjustment by an extra 15mm but this compresses the front springs which made the ride too hard. So rather than modify the chassis and front suspension I fitted AVO 130/95 dampers keeping the original springs from the 120/85 dampers as fitted. Thus I got a 10mm increase in ride height straight away and I needed less turns on the height adjustment which meant that the spring had more travel. It worked for me and I have had no appreciable bush wear since. However I also run the tyres at 25psi front and 28 rear. I still ground at the rear if I hit the wrong road surface and will fit (when funds allow) longer dampers. In the meanwhile I have made up some new rear exhaust hangers which lift the rear silencer by an inch. I am sure you have read the coilover thread but there is some information there too.
Yours Aye Neil

[MalcolmB]

Morning Neil
Thanks for the info. Very interesting. I was wondering if I could fit Longer and softer springs such as 9in x 250 lb which would both soften the ride and enable a lower spring seat setting with more travel and also reduce the spring preload? I am going to remove the shocks and measure the travel and extended length. Do you have these figures for your shocks?
I am feeling more sure that the considerable preload and standard spring rate knocks the hell out of the bushes. I have never had Bush failure on many other cars in my past.
Cheers Malcolm

[MalcolmB]

Hello Neil
Re reading your post again I am a little puzzled how you got an increase in ride height using the same springs. The longer dampers would give you more travel but not more height without longer springs?
In AVOs catalog they show a recommended spring length for each damper, but I assume there is a +/- to this. I think I need to call them and pick their brains if I can fit 9in springs onto the 120/85 dampers. I will likely need to use a spring compressor.
As an aside, i bought a 2.25in C spanner from them for about £5 ish +pp and a very quick service.
Cheers Malcolm

[NATONEIL]

Malcolm
The recommended spring lengths are the same for the 120/85 and 130/90 dampers (7 inch) the advantage the 130 gives me is that it is 1 inch longer. Using the 120/85 damper, to give me the ride height I needed at the front I had to screw the preloading screw up a long way and that stiffened the front springs too much probably because there was not much compression left in them. With the extra 1inch of damper length I was able to use 1 inch less preloading and the springs seem softer. I confess to not being a suspension expert but I think it worked for me. The only reason I have not done something similar to the rear is that I think I will have to drop the fuel tank/remove the body to get at the top bolts.

[NATONEIL]

An interesting day in the garage today. The good news is that you can remove all 4 of the rear coilovers without doing any major dismantling.
My bad news is that I have discovered that the lower polybush on every damper is shot and the resulting metal to metal contact means I now need to replace all 4 dampers (approx cost £560). Four years ago I suggested that owners check the front bushes annually / every 5000 miles. I had not seen any damage to the rear bushes at that time but now I suggest that you look at the rears every 2 years /10000. A new bush is a few pounds, a new damper will cost about £130. My car has 27000 on the clock.

[NATONEIL]

Following on from checking my rear damper units I have now checked my front units. The original set up ate its bushes in less than 7000 miles (although Suffolk Sports cars think that they had been given a poor batch of poly bushes) I replaced my front dampers with one inch longer units at 15K miles and this allowed me to take off 1 inch of spring preload and keep the same ride height and I am pleased to find that my front lower bushes are deformed to half their thickness but still doing their job. They have been replaced and I shall check them each year. I am trying the same ride height spring preload trick on the rear and see how it goes.

[Brunel100]

I know these suggestions re coil spring rates were made some years ago so thought I would ask, what’s the latest opinion on the best set up for a Suffolk ie coil rates, changing shocks, ride height etc. I’m tempted to change my front springs to get a more compliant ride so would appreciate the latest perceived wisdom.