frankenbuggy06 wrote:
what kinda trans is that phillip?
It's a UN5 out of a Renault Master commercial van.
Gear changes are sluggish but it's pretty strong, gears are ~25mm wide on a 90mm spacing, 225mm 4-spider crownwheel, etc, and it fits where the VW box does with a little bit of carving.
The best bit is, that one there cost us £50...which over here is cheaper than a standard secondhand volkswagen box.
The gears are spaced pretty wide but that's a good thing if you still have a low revving VW in there anyway, 1st is very low though, we only ever use it for putting the buggy on the trailer, we've enough power to launch in 2nd and light it up right to the limiter - 4th was a bit long for the power we had with the rotary when racing, that and 5th would be great for cruising though. (Actually, would probably be great multipurpose gearbox over there for you guys, short 1st for climbing, long 4th/5th for riding the trails)
I did have a local engineering firm make us a shorter 3rd and 4th gearset, but I don't think we're going to need it now with the new engine.
Had a long session the other day stringing the car up to rework the geometery on the rear arms - they originally came off a baja 1000 car with 12 inches of travel and were set for very little camber and no toe-in at all, we altered that when we went with the rose-jointed outer mounts, which gave a bit bump-steer at the limits when running 14 inches of travel back there, but shifting up to 17-18 inches really showed the flaws in the setup, especially as the long driveshafts allowed a lot more trailing arm angle to be used:
Anyway, after a few hours of head scratching I pretty much just cut up the prototype arm, and decided to alter the mounts on the car to get things better, which I've been wanting to do for a while anyway.
Lifted the outer joint by just over an inch, and reduced the amount of camber gain by shifting it backwards 1/4 inch, which should drop the rear roll centre and straightens out the toe curve - 1/10th inch toe-in at ride height - and doesn't change much for a few inches either way - 1/10th toe-out at full droop, and 1/5th inch toe-in at full bump, which should keep the back end stable over jumps and when on the gas whilst allowing a bit of rear steer on the brakes in the tight stuff.
Camber is ~2* negative at ride height and runs up to about 7* at full bump, which isn't far off what we had before over the shorter travel, so all-in-all, was worth a bit of time, although now the arm needs redesigning
Passat - there's plenty of those going spare now, you need to do something with 'em!