Reply With QuoteMORE READING....
Driveline 101
Seems a LOT of misunderstanding on driveline angles too....
Heres some info from A driveline guru...
When changing to a lower gear ratio (numerically higher) the driveline speed increases proportionally to the change in the ratio. For example, when changing the ratio from 3.08 to 4.56 there is a 48% change in the ratio and a 48% increase in driveline speed. This means that a vibration that would have been noticeable at about 90 mph is now noticeable at 60 mph. This higher driveline speed makes the vibration more noticeable because while it previously existed at 90 mph, it may have gone unnoticed due to the amount of vehicle vibrations it had to overcome in order to be noticed. If the customer installed taller tires and raised the vehicle before changing the gear ratio, the vibration is probably caused by the lift. This vibration caused by the lift and wrong driveline angles would not be noticeable until the new ratio was installed, since the tall tires and stock ratio kept the driveline speeds too slow for the vibrations to be felt. Vibrations due to wrong angles are usually easy to identify because they are harmonic or cyclic. This means that the vibration varies in pitch or intensity even when traveling at a steady speed. The results is a "whir ... whir ... whir" type of noise.
The solution to wrong angles is easy in theory, but not always easy in practice. There have been many good technical papers written on this subject, so I won’t go into detail now. I will however cover a few of the basics. In order for a two u-joint driveline to be free of vibration it must be in balance, and the angle of the front u-joint must be the same as, or very close to, the angle of the rear u-joint. If there is a noticeable difference in the angles there will be a vibration.
If it is not possible to match the front and rear angles, a constant-velocity joint can be used at the transfer case end with no angle in the u-joint on the differential end. Although it is expensive, and only works if the pinion is not offset side to side from the output shaft, this is the only cure in many lift situations. I have seen vehicles use a constant-velocity joint at each end of the driveline. This is more expensive but will fix any angle problem. Another solutions is to rotate the differential pinion angle up or down to match the front angle. This is usually not easy and can be accomplished with wedges, by moving the spring pads, or by rotating the axles tubes in relation to the differential center section. For some vehicles there are aftermarket kits available for lowering the transfer case or installing adjustable length control arms. Although these may seem like extreme measures, they are sometimes the only way to eliminate or lessen vibrations.
Note: If the vehicle has a differential pinion offset to the side from the center of the output shaft on the transmission or transfer case, the angles due to this offset will not cause vibration. This is because the pinion shaft and the output shaft are still parallel with respect to these side to side angles.
I have seen some lifted vehicles that vibrate no matter how much care is taken to balance the driveline and match the angles. It is one of the things that we sometimes have to live with in order to have a lifted vehicle.
MORE READING....
Driveline 101
Wizard
[QUOTE=Slunnie;661277]Originally Posted by ROVERNIT
well yeah sort of front 4.5 rear 4 and looking more even each day
Wizard
thats the thick and the thin
Ok Guard will be cut flares etc
At this point I have 12 inch shocks front and rear it extends out 7 inch when flat so thats 7 up travel and 5 inch down Rovertym uses 12 rear shocks on 3 inch lift
the springs Dislocate now a little on the front passanger a lot on the rear passanger on the front I have lower retainer on the rear I have upper lower retainer the lower ones are Equip one and the upper on the rear is one me dad made using an exhaust clamp works very well
thats sorted
You now need to look at the ACE system...
It has ample scope for the lift you have, but needs clearance checks and centering again, using different links to centre the rams to their correct position.
Careful attention to the clearance at full compression and full extension MUST be taken, so start measuring!! And testing on an articulation ramp etc...
There should be no need to cut and relocate shock mounts with your setup at all.... You only have 14" shocks, although probably a 'little'too long (12 would have been perfect) its no biggie... and sortable by coil changes...
So, you fit longer and SOFTER coils with a longer free length, that will stop dislocation at FULL droop, but careful of COIL BIND at full compression (again Bumpstops play a part)
Thanks to a use full bit of info from Dobbo he has given me a contact at tuggerah English Auto BBM will sort out the longer links just need to measure against a stock D2 with ACE to centre it but that half way sorted waiting till after new year to arrange this part
The shocks need further attention the front shocks are being pulled out the rear are going up front and the front are being revalved 360/80 perhaps even being lengthened we see about that
the front being at 4.5 inch and rear at 4 Im waiting for Dobinson to make me a new set of rears the are 280 ibs Im thing of going perhaps 260 or 240 ibs depending what advice I get from you Slunnie and English Autos at present at full arc on the ramp the spring dont bind
Ok your money is on the bush where and what brand should I get and do they very in stiffness?
Seeing that is not that bad now an ajustable panhard should be ok shouldnt it
Are the one perchased at expidition exchange fit the ADR thingy
Mate any idea what the legal amount is that I can widen the track on I would love to increase the track bu 2-2.5 inch each side which will place more strain on the shafts again maxis
OK I have chosen those
Ok i'll get to that as required
Ok yet to price that as the old man states he know where they can be done use to be in the trade
it aint a chaep build thats for sure ive attempted to go all quality as you can see
Not really going over 35 any way there huge but ok Ive got 6 pot Mazspeed ones here with huge cross drilled rottered disk hahaha just incase if they fit
[QUOTE=tombraider;661263] So you've done all this, and now the weak points are the drive shafts and CVs and diff hemispheres..
Get some Maxi Shafts, a HD CV and front shaft upgrade and replace the centres with a locker of one type or another... That strengthens the 3rd members...
Whilst your at it, change the Gearing to 4.11's for the larger rubber.
Last time I spoke Maxi they claimed they dont do CV where would recomend ah never mind will cross that path when we get to it sooner rather then later
My crusie control doest work either
thats promising
i'll always run smaller tyres for the road and place a set extream tread for off road i'll eventually get 33 34 for road use and 35-36 of road use
I rarely drive it couldnt help my self yesterday prior that it haded been started for near 4 weeks
again thanks for your help mate its going to looooong looong jerny but if i ever replace my D2 it will be another D2 thats for sure
I wished other where as help full as your self Slunnie and Dobbo thank you again
Last edited by HAK; 30th December 2007 at 04:22 PM.
Swaggie
Just reading through the above posts... when you do the rear ACE links, check for clearance on the bottom of the body, and also at the back of the ram against the Xmember.
The D2 is heavy in relation to a D1/RRC etc, so they run stiffer springs. Also, the big problem with the rear is that there is more weight behind the rear axle and the overhang is greater and so there is more leverage on the rear springs. The D2's will run higher spring rates than the other. 280lb/in as you've suggested will be fine. Actually, I was thinking that you were already running that rate. 240lb/in is soft, but somebodys gotta try it. Also, D1/RRC/Def always look mad on the ramp because they flex crazy at the rear which compensates for their fronts. The D2 flexs fairly evenly... just food for thought. The ramp also generally wont give you much information if you're trying to setup despite what people say. A static load cant imulate the dynamic loads from bumps and jumps which will fully compress the suspension - the ramp wont fully compress.
With Bumpsteer, the Disco has a panhard and drag link that are close to parrallel and close in length. It's not really an issue in my opinion. If you adjust the panhard length, then it's probably a good idea to sort the drag link length also.
You can widen the track by 50mm total (ie 25mm per side) over standard in a Discovery 2 (beam axles front and rear).
The rear shafts will be fine. I have run normal and DC joints in the rear and it makes no difference. BTW, keep that rotoflex if you can, it absorbs the vibrations that will be coming from the front. For the front, you can get standard sized greasable DC joints, you can get 1310 greasable DC joints from Spicer and these will cost a lot, or you can get 1310 greasables and comp ready's from Tom Woods in the states cheaper. The angle of the shafts don't help, but jolting them offroad eventually breaks them. When I was doing a heap of heavy hard 4WDing I'd break 1 front shaft per year. Just touring etc, I haven''t broken any.
Better pads will make the biggest difference despite all of the brake theory. The CV's I got from Maxi were exy+++. You can get CV's that are stronger, guaranteed and a hell of a lot cheaper for the D2 from Ashcroft transmissions (get your 4.11's from them also). The Stocker D2 CV is really weak and 35's will break them unless you drive like a girl (about 3700lb/in). The Ashcroft will break at about 7500lb/in which is up there with the Longfields. You diff will explode before the CV's break.
For manuals you must correct the speedo to suit the diff gears and not the tyre size to maintain the CC function. Autos will allow you to do whatever you like.
There is no max tyre size spec at least in NSW.
Cheers
Slunnie
~ Discovery II Td5 ~ Discovery 3dr V8 ~ Series IIa 6cyl ute ~ Series II V8 ute ~
Swaggie
Here is Ashcroft website for:
D2 CV's
Ashcroft Transmissions
4.11 gears. Dave has told me that these can be run with the rotoflex unlike other replacement diff gears.
Ashcroft Transmissions
Cheers
Slunnie
~ Discovery II Td5 ~ Discovery 3dr V8 ~ Series IIa 6cyl ute ~ Series II V8 ute ~
Wizard
Thanks Slunnie
I think I'll go in this order
1.the links, shock rates, and new spring to level the rear I'll stick to 280 ibs adventually the rear bar will need to be changed and steel one would be the only option I imagined I need a donor stock D2 to measure the ACE up I'll do this in the January
2. the Radius arms from QT look more appealing but as tombraider advised legal wise i'll go with the bushes if there the the only option
3. the shaft, CV and the 4.11 now I remeber reading some where that in order to fit 4.11 something needs to be machining on the new ARB lockers is this a fact
3. Next will be some flares, steelies and rubber I love my coopers but they only make a 33's 285/75R16 or 305/70R16 and 34.5's 315/75R16 or a 37's 325/80R16 and nothing in between 50mm widen track by offest or rubber or both total
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