JohnT

I am toying with the idea if getting Leda B suspension fitted to my STI V. Has anyone had this fitted? If so does it improve the understeer in wet and 'skitishness' at high speeds? Will fitting 17" wheels inconjuction with the suspension further improve the handling?

MorayMackenzie

1.Yes
2.Debatable, they will improve grip. It depends if you want more grip on bends at the expense of gradual break-away. IMHO I think they would be an improvement.

Moray

MorayMackenzie

1.Yes
2.Improved grip at expense of some of the gradual break-away, important trading one handling characteristic for another. IMHO This would be fine with the LEDA setup.

Moray

(Two posts: I hit the clear field button and thought I lost the previous post! Whoops!)

[This message has been edited by MorayMackenzie (edited 19-08-1999).]

Saj

I have both fitted the suspension was done first for the first couple of days I was apprehensive handle quite settled down but now drives like a dream 17' fitted 4 weeks later no tyre roll and beleive it or not, not much harder but do play around with the settings depending on the sort of roads you use.

Saj
S3 WRC

mike_nunan

Get LEDA C if you can afford it. I know the website says it's for rally use, but the average secondary road is much rougher than a track, which is what the type-B units are set up for.

With the gas (type-C) units you get a secondary, softer damping action for small suspension movements. If you hit some rough tarmac they'll cope with it better and give you a bit more grip. You should also get less NVH.

-= mike =-
(Who got the "B" option and always sorta wished he'd gone for the "C"s)

JohnT

Thanks Chaps!

I will definitely be getting either the B or C option. Are there any knock-on effects by having this fitted and how easy is it to adjust?

Cheers,

JohnT

david

Mike.

Are you saying don't go for Leda B unless you plan to do alot of track days? I've just booked my V in for the Leda B option, but now you've put doubts in my mind.

Any other Leda B people like to comment?
Pete, can you add to this?

Cheers,

Dave

mike_nunan

No, I'm just saying that LEDA C might be marginally better for road use. I suspect the difference is marginal -- and I'm basing my comments on technical deductions rather than experience, always a dangerous thing to do! The only way to find out for certain would be a direct comparison on otherwise identical cars, not something I've had the chance to do unfortunately. Anyone out there able to offer comment?

[Edits...]

Oh yeah, damper adjustment is just a matter of turning the front wheels out to get at the adjustment *****. On the back, you can reach them easily if you've got skinny arms and/or the car isn't lowered too far. Otherwise you have to lie on the ground and stick your arm up behind the mudguard, which I would tend to avoid doing on wet days in your best shooting jacket.

Height adjustment means taking the wheels off and screwing the spring platforms up and down using a special tool. Easy enough to do in preparation for a track day if you want.

[This message has been edited by mike_nunan (edited 20-08-1999).]

Pete Croney

All dampers (all makes) use oil which is forced through valves to create the damping action. This action causes the oil to heat up and if the oil gets too hot, it can boil and the damping effect deteriorates.

To prevent this, there are a number of things you can do...

1. Use a damper design that carries "too much" oil.
2. Design the valving so that the oil is always traveling in one direction, irrespective of the wheel's direction of movement (up or down). This ensures the valves always work with cool fresh oil, not oil that has just been heated by the valving.
3. Pressurise the oil to raise it's boiling point.

When people describe dampers as been "gas" units, it means they use option 3. Most do this by pressurising the whole unit and then sealing it (as the OE units do), but if you mount the gas externally and have the cannister feed just in front of the "bump" valving, you can get a secondary effect. As any gas is slightly compressible, mounting the cannister here can let the gas slightly cushon the initial shock of the wheel movement, allowing a more linear acceleration of the damping oil.

If you think about the work the damper must do on a gravel rally or rallycross car, there is no comparison with the work done on tarmac.

In the real world, driving on the road, it does make the system slightly more compliant and gives a small increase in grip on bad, wet roads, when compared to a non gas unit. Option C has a slight advantage here.

On a track, wet or dry, the suspension is distributing car weight and controlling body roll, rather than soaking up bad surfaces. The control given by option B units makes these units the preffered option.

Wet grip is as much about tyres as suspension but in the wet you want soft compliant suspension and a small amount of body roll. I always back my dampers off if going for a blast in the rain.

Only Leda and Proflex units use all three of the above ways of maintaining damper performance.

I discussed suspension dynamics in the last True Grip. If you aren't in the SIDC, join and ask for a back issue of TG3.

mike_nunan

There you go - B for track days and C for road use. If there are any track-day nuts out there who've bought option C by mistake, I'd be happy to swap units with them and pay the price difference...

-= mike =-