Stepman

Kali, just a thought. Since you mentioned angles. I would try to get your shaft angles to 3 degrees or less. Also, make both ends the same, but opposite. I believe that you can also shim the axle to make this easier.

kalli

well on club meeting everyone who had any kind of puller brought it and last night I changed the steering over. I had to take the driver side header off to get the puller on. what a nightmare. 1 hour job->3 hour job :-(
well anyway the steering is in, the old crap out.
I gained about half an inch clearance, so I guess when i drop engine by half inch I'm where I have been before ... ?! I was hoping for a bit more.

anyway ... the steering got a bit tighter with all new balljoints and at least I can now say that all 6cylinder remainders are gone from my car :-)

maybe next week I'll give it a lash. we have to get 2 cars on the road for a show on weekend, so I'll be a bit busy up until then

Stepman: ya, the gearbox is 6 down, the pinion 4 up. so it's inbetween the two, but the working angles at u-joints are too high (driveshaft to gearbox+driveshaft to pinion). it's almost 10 degrees added up. if i raise tailshaft a bit (with dropping engine) the whole thing will be straighter. further I hope with the adjustable mounts I can move theings sideways a bit to get a straighter line in the driveline

OCHOHILL

I may not be understanding your statement, so bear with me. You want the imaginary center line of the gearbox and rear differential to be parallel. Ideally, they should stay parallel. This is regardless of angle as long as it is within the working range of the u joint. If they can't be set parallel, my local driveshaft guru told me to keep them within 2 degrees and they should be fine. It sound like you are right at the 2 degrees. I don't remember for sure but you should be close to ideal. I don't recall what allowances are made for torque rotating the diff on the springs. If you set them static parallel, they won't be when driving due to torque acting on the leaf springs.

I would try shimming the tailshaft 2 degrees and see what that does. It's easy to do at the tranny mount.

kalli

that's how I understand it as well. the tailshaft/pinion is not too bad, but the working angle is. it's not exact (as I measured ages ago), but imagine: gearbox 6 down, tailshaft 4 up and the drivershaft perfectly horizontal (0 deg). so I have a working angle of 6+4 deg=10. if the tailshaft comes up the tail is let's say 4 down, it will lift driveshaft in front, lets say hanging at 1 degree. i'd then have 4 at tailshaft, 4 at pinion, and 3 each working angle =6. sounds an awful lot better to me.

I'd love shimming the transmount as you say it's very simple and straight forward. There's craplots of room between tailshaft and car floor. however there's only very little room just front of the mounting. There's a structure going across the tunnel which is very close to hit the T5. Any lifting will cause to hit it :-(
I even thought about cutting a piece out of there ... that's how I ended up with the idea of lowering the engine

OCHOHILL

If it was cheaper I would try shimming the rear diff 2 degrees up. I am curious why it vibrates only above 75 mph.

Does it fibrate under heavy accelaration?

kalli

1st gear wheelspin, 2nd gear whooooooooooo, 3rd gear whoopoooooo and at ~80mph it kicks in and I have to immediately decellerate back to 70mph. I can't tell the speed when I'm flooring it, the needle seems to stick to glass from accelleration forces :-) around 75-80mph no matter what gear. can reproduce this with cruising in fourth or fifth as well. could easily shim the rear up, even have the shims for it. however I guess the problem will be worse then
it will look like that \/\ instead of \-\ now. the working angles would be even worse