P.s. I meant to say... I sympathies with you on this one! Wheels/tyres are just a bloody nightmare. Took me several weeks to find the right wheels/tyres that matched all the requirements etc for my Saab. Different sizes, widths, offsets etc etc.

Thanks very much for all your advice, Phil, and I'm glad I'm not the only one.

I advised my insurer of fitting '91' load rated tyres instead of '94' and they weren't bothered, but that's just one!

 

With regards the Greenline/towbar/weight situation, as well as the weight of the bar there is a 'nose weight' applied onto the bar by an attached caravan. I've never towed anything, but I think the nose weight can be as much as 60 kg, and that is loading onto the car wheels.

 

I asked a few tyre companies if the ride quality was any different between those different load ratings. The answer was a hesitant 'yes', the tyre sidewalls are stronger (the tyres have a higher maximum air pressure as well iirc) and so probably a little stiffer. I don't think it's supposed to make much difference in practice.

 

A 205/55 x 16  '91'  is a very popular tyre indeed, so the prices are very keen, but a '94' is about 20% dearer. 

 

It's worth noting that as the contact patch is smaller on the 16" it will run a higher tyre pressure than your existing 18" wheels. Fwiw, The tyre techies (Goodyear) said the recommended tyre pressure on any car was arrived at through car stability testing as much as anything.

 

Just to confuse, another option might be new shocks and perhaps springs. Aftermarket items are usually performance orientated, so worse for you, but there were Koni FSD (Frequency Selective Damping) shockers listed for the Superb which might help a bit, at a price! They come quite well reviewed but some early models seemed to leak prematurely. I don't think many (any?) on the forum have fitted them. But their USP might be what you seek; softer damping over sharp bumps, but no floating over undulations.

 

 

Edited 27 April, 20179 yr by CombatWombat

43 minutes ago, CombatWombat said:

It's worth noting that as the contact patch is smaller on the 16" it will run a higher tyre pressure than your existing 18" wheels.

 

 

 

The contact patch is smaller because of higher pressure. 

The speed rating is also important as if it's too low your insurance will be invalid , doesn't matter how slow you drive

These seem to match all the criteria, the seller telling me when I phoned them that the load index is 94V...

 

http://www.ebay.co.uk/itm/182526179393