Final tyre question (hopefully)

[Shaun_E]

Following my other threads on tyres and after checking prices and availability I have narrowed down the choice to either of:

1. A replacement set of A021Rs 185/60 13"

2. Change to CR500's 175/55 13"

 

Has anybody made the move from A021R to CR500?

If so I have 2 questions:

1. The CR500's are slightly smaller diameter, so is the ride height difference noticeable? My car has very little ground clearance as it is.

2. Are the CR500's noticeably better performing either on road or track or both?

 

The car is a Superlight so in theory I can adjust the ride height (if I get the tools and find out how!).

 

Thanks,

Shaun

 

 

Yellow SL #32

[robmar]

Shaun_E I recently changed from 32's (185 60 13's) to cr500's (175 55 13's) on my superlight so can possibly give you my expereinces

 

1. ride height - it was noticable for me as I started to hit th efloor getting over a slight hump on my drive after the change, I got it raised slightly when I had some other geometry tweaks and is now better

2. performance - on the road they appear as good if not slightly better than the 32's, especially in the wet, on the track in the dry I reckon the 32's have the edge, this being based on 1 session at llandow at the weekend. I have no emperical evidence to back this up by the way.

 

The biggest difference I found is motorway driving, as it has knocked the rev's up a few hundred to maintain the same sort of speed, plus the speedo is even less accurate

 

As an all round tyre they a pretty good, I have no expereince of 21's I am afradi so cannot give a direct comparison....

 

hope that helps

 

rob

[Shaun_E]

Rob,

Thanks - just the sort of reponse I was hoping for although the answer isn't . 21's are even taller than 32's so I think I really will notice the ride height difference moving to CR500's since I already seem to hit every bump in the road with my sump 😳. Guess I'll have to get more 21's until I can stretch to a flat floor set up and new tyres at the same time. Either that or I'll have to get the necessary tool(s) and adjust the height myself - slightly worrying.

Don't like the sound of increased revs much either.

Cheers,

Shaun

 

Yellow SL #32

[robmar]

I am just down the road near wokingham (not really Elbonia)

 

so if you want to give a set of cr500's a try let me know

 

rob

[KevSull Too]

Shaun,

 

I've raised the ride height of my SL after twonking my sump on a cats eye!

If I can do it, anyone can!

 

Since doing it I have also found the handling to be 'nicer' for road use. I'll try to explain - the handling used to be razor sharp, and go-kart like (I was always worried about losing the back end in a corner) -- it's now slightly softer and much more predictable, I can hang the rear out on roundabouts whenever I like, but it's ultimately not as fast through the bends. Much more fun though and I'm not so worried pressing on.

 

I'm running CR500's as these are what came with the car. Thinking about going to 21's or 32's next time round simply for the cost saving as I'm getting more interested in track days.

 

😬You laugh at me because I'm different, I laugh at you because you're all the same. 😬

 

[Shaun_E]

Rob

Thanks for the offer. Are you around tomorrow or Thursday evening? I would like to try them and measure the ride height difference if that is possible.

 

Kev

How did you change the ride height? Don't you need some special "C" spanners? I didn't get them with my car.

If you are going to do more track days I wouldn't recommend 21's for the dry - I completely trashed mine on Saturday but, they were superb at Llandow last year in the pouring rain and standing water.

 

Cheers,

Shaun

 

 

Yellow SL #32

[robmar]

Weds - is probably best for me, drop me an email off line

 

I also have the c-spanners somewhere so can show you what to do with regard ride height setting

 

rob

[Mango 7]

Shaun, I have some c shaped spanners if Rob can't locate his, and if you fancy a trip to Penn? E me off line for directions if necessary, otherwise, best of luck and see you soon,

 

Jeff

[KevSull Too]

Shaun,

 

I just losened the locking nuts with a screwdriver and a hammer, grabbed the shocks and springs and gave them a bit of a wind. Did the same number of turns for all 4 and Bob's your aunties live in lover!

 

Piece of pi55

 

😬You laugh at me because I'm different, I laugh at you because you're all the same. 😬

 

[Shaun_E]

Thanks for all your help and suggestions. After all that I've decided that the easiest route is to stick with what I know and replace my 21's with more of the same. I haven't spent enough time on track to understand how any changes to suspension settings will affect the performance and it would worry me if they were changed now. I need to replace the tyres immediately as the current ones are definitely past it and I don't want to leave the car in the garage any longer than necessary.

Rob - thanks for your offer and sorry if I've messed you around - see you at the next track day (I think we met briefly at Silverstone novice day).

Kev - thanks for your tips.

Jeff - thanks for the offer, see you at the next Penn meet.

I have learned a fair bit from this discussion - not least that I have a lot more to learn! I started looking at tyre diameters vs rolling circumference or revs/mile and realise that there is no easy way of working this stuff out - you have to go on empirical evidence. I think the only real way forward is to have an extra set of wheels/tyres for the track where it is easier to experiment and make comparisons.

Thanks again,

Shaun

 

Yellow SL #32