Official Seat Sport mods- help needed!!

[Wolvescupra]

Hi all! Just heard from a dealer in Leicester that (basic) offical tuning mods are available for the new Ibiza which is more than my dealer in Wolves can manage (still waiting for the brochures to arrive!!!). These include strut braces, suspension kits, alloys etc.... call your dealer for a brochure. Anyway, my question is....has anyone got any experience with these mods? I'm interested in the 'suspension' for my Ibiza Cupra 20VT which, when I was told, would drop the car 40-60 mm sounded promising. Sounds even better cos the warranty of the car is unaffected. Secondly...has anyone noticed that the front track is visibly wider than the rear? Is there any way in which I can sort this out? Would wheel spacers help? In fact can anyone tell me if wheel spacers aid roadholding/handling at all? I was offered them as a 'cosmetic enhancement' when I owned a porsche boxster but everyone went very quiet when I asked if they were performance enhancing! All comments gratefully received. Thanks.

------------------

[2001 Seat Ibiza Cupra 1.8]

The reason for the narrow track width in the rear is due to the lighter weight of the rear compared to the front. The weight bias of these cars is about 70/30 so the narrow track width is needed to concentrate the weight of the rear on the tires. If you make the track width wider you lessen the weight distribution on the tires, or spread the load more thin. It will make your car handle terrible in the wet. The advantage in the dry will be that when you turn in to a corner at high speed your car will be less likely to push to the outside of the turn because the rear end will want to swing around. I wouldnt mess with it unless you are pretty sure you can get it right. The factory has some pretty smart guys with big calculators figuring out weight distribution, and their set up is the best for everyday driving in all conditions.

------------------
2001 Seat Ibiza Cupra 1.8t

[Wolvescupra]

Thanks for your reply. Can you just clarify one thing for me though....if the weight distribution is 70/30 on the existing track, how would widening the track alter that distribution? For instance if the weight over the rear 'axle' is, say, 400 kg then surely that 400 kg is distributed in the same manner between tyres on a track of 1390 mm or 1430mm (at least when the car is at rest). If it isn't, I would like to know where that weight has disappeared to!! The effects of a wider track when the car is being thrown through corners is what really mystifies me....surely the wider the track is, the more secure the handling as it would reduce outside tyre loading (by reducing the weight transfer), giving a (very slight) more even ditribution of weight between the rear wheels thus giving higher levels of grip. This should preoduce (safe) understeer rather than the wild oversteer that you describe in your reply. As you can see I'm very confused about the whole matter and would appreciate a reply from anyone who can help. I'm not saying anyone's wrong here, I'm just interested to find out a little bit more about the engineering aspects of handling. Thanks!

------------------

[ibizacupra]

Weight distribution vs track is'nt quite like its been described.
Stability is the reason for wider track rear end, to help balance front to rear dynamics of the chassis/suspension setup.
Weight is an issue, but not with respect to the track width and corner weights etc.. they would remain the same.

Narrow track rear can lead to a more lively rear end (oh err) which can lead to lift off oversteer, which can catch people out. the wider rear track would tend to reduce this effect and produce a more neutral/understeer type handling. It is a preference thing.

Understeer is'nt my choice, and my sprint car has neutral balance through the corner unless trail braking/left foot braking where it then moves into oversteer, and you can nail the power to pull you through the now tighter line. - This is on a race track however.
On the road, mid corner, where something jumps out in front of you, and you say jump off the throttle, and/or onto the brakes, you are quite likely to swap ends via oversteer.

There is of course the cosmetic aspect also for some people.

regards
Bill
http://www.seatcupra.net/forums/smile.gif

------------------
http://www.badger5.co.uk

[This message has been edited by ibizacupra (edited 05 August 2001).]

[2001 Seat Ibiza Cupra 1.8]

Track width has everything to do with weight distribution. If your car only had one tire in the back, in the middle, there would be more pressure applied to it on its contact patch than if you had two tires mounted 2 feet out side the car.

------------------
2001 Seat Ibiza Cupra 1.8t

[ibizacupra]

What a stupid arguement to put up! (sorry no offence intended - but come on guy!)
We're not talking track width on a 3 wheeler now....and relative weight on a given "single" rear wheel. This is'nt a Reliant Robin forum I've stumbled into by mistake?

Width and 2 rear wheels..
The weight balance is front rear from the original post - 70-30 f/r according to that post. (be that right or wrong)
Contact weight on the rears is the same front/rear whether it has slightly wider track or not (assuming we're still talking a 4 wheel car here!)

If you were talking wheelbase, then leverage would apply front rear... but you are not, you are talking track width. Chassis balance is the thing on wider track... Ask why the F2 Ibiza had a wider track = high speed stability especially on tarmac stages.

Bill


------------------
http://www.badger5.co.uk

[This message has been edited by ibizacupra (edited 06 August 2001).]