What do I fit?
There are two sizes of clutch fitted to the L series. The non intercooled engines got the 215mm clutch, the intercooled ones got the bigger 228mm ones. You can swap the smaller one for the larger one if you also swap the flywheel to suit which will help with any slipping problems.
If you have the larger 228 clutch and the standard one is slipping and in good condition then you’ll be looking at fitting something a bit beefier. There are a few options out there as upgrades.
3 basic types of upgrade have been used so far to my knowledge
These replace the standard disc of friction material with usually 4 pads of material. The less material there is the harder it is pressed into the flywheel so the more grip it has. They tend to be a bit on-off and you don’t want to slip them a lot, but they are the heaviest duty upgrade generally.
Modified friction material – Kevlar
These clutches look a lot like the standard clutch but uses Kevlar as the friction material which gives more grip. It also has cutouts in the friction material giving a smaller surface area and so you get a stronger pressure applied to the friction material and so a heavier duty clutch. They are friendlier to use than the paddle clutches but they aren’t as soft to use as a standard clutch.
They are available with a solid centre and with sprung centres like the standard clutch has. Personally I’d not touch the solid centres as you’ll be transmitting more shock loads to the gearbox and the gearbox doesn’t like that.
Lastly there are people out there who are offering upgraded clutchs that look very much like the standard ones. Some of these are genuinely upgraded units with stronger spring plates, which will give a nice soft feel (albeit with a marginally heavier clutch pedal). However some are simply quality OE units that are painted pretty colours and sold with a large markup.
The standard clutch is reliable up to 200ftlb and probably ok up to about 250ftlb under ideal conditions, which is ok for most modestly tuned vehicles.