Thinking about a new set of wheels and tyres ready for the new hillclimbing season, currently run Rover Sportpack 6J13s (7kg - ouch!) and Toyo R888 185/60/13 (7.9kg). Not much choice on tyres - will have to be Yoko A048R 175/55/13 to slightly lower gearing, but what are your thoughts on wheels? Current favourites are Force split rims (3.4kg), solids would be easier, cheaper and stronger but heavier? Does anyone have any good/bad experiences to relate, or thoughts on the likely effect of the saving in unsprung weight?

I don't think you will find wheels much lighter than the Force split rims.
A Compomotive CXR cast wheel is about 4.6Kg (I like them).
As for tyres, the lightest are likely to be Avon ACB10 but as a road tyre they are not a good choice as wet weather grip is very poor compared to the A48Rs.
Size for size the Avons are about 2Kg lighter per tyre.
For a competition car saving on unsprung weight is a primary goal.
For the road you need a wheel/tyre combination which can stand up to potholes and speed humps

Compomotive CXRs were the lightest one pieces wheel I could find when I was looking for some it was why I bought them, plus I photoshopped them and liked the look.

I really wanted image three piece simular style but could not justify the cost and as my car is a road car, i.e pot holes etc.

Neil

Not sure if there in you price range as they are rather silly price. But these http://www.demon-tweeks.co.uk/Performance/Wheels/View_Wheels/Rays_TE37/2101/0/179153 are nice and lighter than a set of splits I have here!

The TE37 are over 5Kg per wheel so not as light at the split rims, but these are nice wheels, these are very expensive as Rays wheels appear on F1 cars and some touring cars although from there racing range. in TE37 range they only do PCD for 100mm and 114.3mm, I have to admit I don't know what PCD you require.

Thanks for all the advice guys. The Avon tyres sound interesting (and light!), but having only just sorted out the handling I'd be a bit nervous fitting crossplys I think - unless you know different of course! I too love the look of the CXRs, if anyone has a set for sale I'd be interested. I'd be keen to stay close to our current set up of 6x13, +23mm offset, 111 backspace, as I know this works on the car. The Rays look amazing, but yes, beyond budget I'm afraid

I might be tempted to sell mine at some point, but I need to decide what direction I want to go and that may take a while.

Let me know if you do decide to part with your CXRs Neil - I may have to make a purchase pretty soon though.