Pour votre info, voici la réponse d'AEV JIM (ingenieur Nth degree) sur leur kit pour JK :
Hi Fabrice, and thanks for posting your JK and your exploits here on our forum! You have a great rig there that even we're jealous of (for the diesel engine!).
JeepinJon has made (as usual) some pretty good suggestions/observations already, and only you will know what works in the end since the best we can do is guess...unless you want to fly me out for one of your raids. I'd be happy to do 'on sight evaluation and assessment' and my rates are reasonable!
As a starting point, I am confident that our JK suspension is THE exact suspension for your Jeep...it's exactly what we built it for: a daily-driven JK that sees occasional 'raid type' use. Our progressive-rate springs and tuned-to-match (by us) Bilstein 5100's are specifically meant to be very pleasant for unloaded commuting, but still handle the loads and speeds of off-road adventures such as yours. You're probably at the very highest end of the range of use that we had in mind, but I think that mainly means adding some things to our system (see below), rather than needing to piecemeal together an un-sorted mix of one-off parts such as what JeepinJon was suggesting from Evo...that's how race cars are built but of course race vehicles spend more time sorting their stuff than building it...so only buying the parts means the majority of the 'investment' to make it really work is still yours to do.
At a previous employer (before I even started Nth), I spent a considerable amount of time developing a fairly conventional suspension (i.e. like our JK suspension) with strategic enhancements for higher-speed off-road travel. Those vehicles are now in service with the U.S. Border Patrol and have tripled the service life from what they had before. The key was JounceShocks (Light Racing's improvement on the otherwise-primitive 'air bump' that others sell). Adding those alone (with proper tuning - they're on-car adjustable) nearly turns a regular suspension into a desert race vehicle...perfect for you Fabrice.
Currently Rubicon Express makes a JK-specific kit to install the LightRacing JouncShocks in a JK. Add that to our suspension and I think you'll be amazed at the results. Beyond that, JeepinJon's comment about your roof rack is valid: adding weight (cargo) to the roof degrades handling VERY rapidly. Converting it to aluminum won't make much difference - it's the cargo you put up there that really matters. Since our springs should do a pretty nice job of handling your dual-sport needs, I would advise keeping the stock front and rear stabilizer bars, because if you add a thicker rear bar, it will make your Jeep dangerous to drive unloaded on slippery surfaces.
Hope that helps...
Jim
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I don't think you were as off as you're making yourself sound JJ, and besides only Fabrice knows for sure! He has mentioned rocky trails a >60mph, so that's fairly fast running but still not really out of our intended performance envelope (depends on how rough - read on). The ability to handle a given RMS# (a quantifiable measure of surface roughness used for military mobility testing), is heavily tied to wheelbase and suspension travels - the faster you want to go on a given RMS, the more of both you want to have...but especially the travel (and of course proper frequencies, valving, etc.). The cool part is that the JounceShocks transform the usual equation and allow more speed with less race-vehicle-like travels...so you can have a more practical suspension that can still do higher off-road speeds. That in turn allows you to focus on a good base suspension for a dual-sport rig (i.e. our JK systems). Then for what Fabrice is doing he might need to add the JounceShocks, dial them in a bit, and the grin he'll have will wrap around his ears...
Jim
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A plus pour les photos du montage de mes kits et les premiers essais.
Fabrice
