| Author | Message | ||
     mark peterson (Mspeters) New Member Username: Mspeters Post Number: 1 Registered: 07-2003 |
I'm tearing into my D1 after 7 years, doing a 3+" OME based lift on 97 Disco 1. 764/762s, with OME FJ80 LRTs in front & bilstein 7100s in rear, with RTE trailing links, CV driveshafts I boiled down to two choices for front. 1 - Custom Swivel housings from http://www.tomcatmotorsport.co.uk/parts.html same LR OEM supplier, made for more castor. in theory this would preserve the driveshaft angle at diff. for vibes, and can use a single-ended Cardan driveshaft v twin-ended. 2 - Offset Forged caster corrected radius arms from Scorpion(UK). Not very high on the welded (sectioned and overplated) or heated/bent offerings from within USA. Any suggestions. | ||
| Shaun Power (Shaunp) Member Username: Shaunp Post Number: 102 Registered: 05-2003 |
What if you took off the swivel housing and got someone with a milling machine to slot/redrill the bolt holes so you could rotate them to give correct castor. | ||
| John Friederich (Jfriedlvcmcom) Member Username: Jfriedlvcmcom Post Number: 60 Registered: 02-2003 |
I lost castor w/2" OME on my D2. Front TrueTrac fixed my steering perfectly, and gives (slightly) better offroad perf as well. John F | ||
| John Lee (Johnlee) Dweb Lounge Member Username: Johnlee Post Number: 275 Registered: 03-2003 |
Mark, I think the front Truetrac is the best solution to the caster problem. It cures the wandering problem, and you get a stronger front diff and better traction to boot. Those Scorpion racing arms are welded, I believe. At least they don't look like one-piece forgings. Rather, they appear to be welded together from several different pieces. | ||
| Chris Marcel (Gumarcel) Senior Member Username: Gumarcel Post Number: 846 Registered: 11-2002 |
I am retarded and fell stupid asking this question but what is a "castor" and what does it do. I keep reading about it but have no idea what it means. | ||
| John Lee (Johnlee) Dweb Lounge Member Username: Johnlee Post Number: 277 Registered: 03-2003 |
It's "caster". Check out: http://www.southmainauto.com/images/caster.gif Imagine your front wheels turning left and right. Those wheels turn on axes. Those axes are not vertical. They are leaned backward. The amount which this angle differs from a vertical line is "caster angle". On our Rovers, when the vehicle is lifted, the caster angle changes because the radius arms no longer point straight forward and tilt downward as more and more lift is added. The front axle's relationship to the radius arms is fixed. As the radius arms point downward, the front axle rotates downward (pinion points upward) and the caster angle is lost or lessened. This makes the vehicle want to wander and not self-correct the way it did when the radius arms pointed straight forward. It's similar to the fork on a bicycle. Imagine how a bike would handle if the head tube were verticle and the fork were perfectly straight without any rake or effective rake. Riding this bike would be difficult. | ||
| Chris Marcel (Gumarcel) Senior Member Username: Gumarcel Post Number: 847 Registered: 11-2002 |
Thank you John now I understand, that was very helpful! | ||
| Shaun Power (Shaunp) Member Username: Shaunp Post Number: 103 Registered: 05-2003 |
I think in the old days it was called king pin inclination. Mark have you also fitted the Old man emu castor correction bushes? They are about $100 Australian. www.arb.com.au | ||
| Brian Dickens (Bri) Senior Member Username: Bri Post Number: 525 Registered: 08-2002 |
I hear all kinds of bad things about the bushings. Try the swivel balls and let us all know how it works and how much they cost. GBR in the states redrills swivelballs I believe. I believe RTE does not do it anymore. | ||
| Bill Bettridge (Billb) Dweb Lounge Member Username: Billb Post Number: 880 Registered: 02-2002 |
I've had both the bushings and the TT. The bushings are useless - they limit articultion and delaminate in a very short time (as with all urthanes). The TT has been great - takes a little getting used to the handling, but it tracks straight and true. Bill | ||
| Robbie Donaldson (Robbie) Senior Member Username: Robbie Post Number: 417 Registered: 02-2002 |
i was actually having this debate with myself all of yesterday. one question I have, by getting a TT, does it just mask any issues? as in, if you have a loss of caster, will it cause something to prematurely wear out or break? my question make sense? | ||
| Rob Davison (Nosivad_bor) Dweb Lounge Member Username: Nosivad_bor Post Number: 719 Registered: 02-2003 |
there is only one correct way to do this short of forging new arms or relocating the mounting of the arms. that is to have the holes in the swivel ball realigned. rovertym used to advertise it on the website but i dont see it anymore. EVERYTHING ELSE IS A BAND-AID. the TT works, but it is just hiding the real problem. rd | ||
| Steve Cooper (Scrover) Senior Member Username: Scrover Post Number: 411 Registered: 09-2002 |
Rob, I think the question is, what is the consequence of 'just hiding the problem'? Tire wear? If the only issue with loss of caster is steering wander, doesn't the TT solve the issue as opposed to hiding it? If the TT gives you back the self centering, who cares what the caster angle is, or am I missing something? Curious Steve | ||
| Chad Meyer (Ccdm3) Member Username: Ccdm3 Post Number: 132 Registered: 07-2002 |
Another option is the SG 3-link. I have one set up on my truck and have been pleased with the results. It allows for adjustable cater and pinion angle. | ||
| mark peterson (Mspeters) New Member Username: Mspeters Post Number: 2 Registered: 07-2003 |
Thanks for the inputs. I'll pursue the swivels. I wasn't aware GBR offered this service; at least not on the web site. RTE decided not to offer this castor-correction service, they needed to purchase one more piece of equipment, and didn't get enough customer interest. The swivels from Tomcat Motorsport are made for LR based buggies, and are made by the OEM manufacturer with extra castor, not welded & redrilled. If the Scorpion Racing radius arms are indeed welded, as others, thats a no for me. I'm trying to avoid the Tru-Tracs, and use ARBs. I have in dual Tru-Tracs in my CJ-5. Not well behaved in tight turns on snow/ice. | ||
| Rob Davison (Nosivad_bor) Dweb Lounge Member Username: Nosivad_bor Post Number: 721 Registered: 02-2003 |
Steve i don't know what the repercussions, if any, are for using a TT for castor correction. all i am saying is the Right way is to redo the balls. i reckon over ten years of driving the effects might show. I doubt I'll have my truck much more than a year from now, after i am done restoring i think i'll sell and get a 95LWB. i've had a front TT for a few months to help with my issues but i plan on getting the balls done once i have a front bumper and winch because it will effect my lift measurement. will let you know at the end of summer if i can tell a difference. at this point it's just a matter of doing it the right way because that's the way i like it done. rd | ||
| John Lee (Johnlee) Dweb Lounge Member Username: Johnlee Post Number: 280 Registered: 03-2003 |
I have to agree with Steve here. I don't see how the TT is any less "right" than altering the swivel balls. As far as I know, there is no detrimental effect on the vehicle from loss of caster angle. The only "bad" that comes from it is steering wander. In fact, I would prefer to put in a front TT to making my swivel balls into swiss cheese. I think adding the TT is actually less intrusive to the vehicle and reversible as well. | ||
| Mike Rupp (Mike_rupp) Member Username: Mike_rupp Post Number: 235 Registered: 02-2002 |
John, The only downside that I can imagine using the TT is that the steering box might have to work more than before. With the TT wanting to pull the vehicle straight, the box might get more wear & tear. Who knows? It might not make a difference; I'm just playing devils' advocate. All things considered, the TT is probably the best solution. | ||
| John Lee (Johnlee) Dweb Lounge Member Username: Johnlee Post Number: 281 Registered: 03-2003 |
Yeah, the steering box could suffer more wear and tear. I don't think this is a problem if everything is set up correctly and working right, but I guess it could be a problem if the truck isn't tip top. The TT exacerbates any imperfections in alignment or tire balance. If alignment or tire balance is off, the TT will pull to one side instead of constantly centering. Perhaps this could put more wear and tear on the steering box. But if the alignment and tire balance are good and the TT is centering, I doubt there is any wear and tear on the steering box. There might even be less. Who knows. All I know is, my steering box is still perfect after about 3-4 years with the front TT on there. | ||
| RVR OVR (Tom) Senior Member Username: Tom Post Number: 800 Registered: 07-2001 |
I have both the RTE castor corrected HD radius arms and the TT. The setup works well, I guess I get "more" centering than I need. I think that the RTE arms are bent then reinforced with plates, not welded together, so strength should not be an issue. Either way, most likely stronger than the stock toothpicks. My only apprehension regarding the TT solution is financial. If you want to do gears at a later date and have to pay for the service, you will be paying twice, once for the TT install, and again when you do gears. Just some food for thought. Tom | ||
| Steve Cooper (Scrover) Senior Member Username: Scrover Post Number: 412 Registered: 09-2002 |
Cool. Well, I've only had my TT in for a few days but so far I don't see any need for additional caster correction. Doesn't sound like anybody has experienced any detrimental effect unless you don't like the feel of the TT or you need a true locker. It gets my vote. Besides, if you correct the caster on a lifted vehicle, doesn't that increase the pinion angle? BTW The Scorpion forged arms are still in the development stage. My guess is they'll never see the light of day. Steve | ||
| Rob Davison (Nosivad_bor) Dweb Lounge Member Username: Nosivad_bor Post Number: 724 Registered: 02-2003 |
only if you use the correct arms steve. just becasue i'm not smart enough to be able to figure out what negative effects the TT with incorrect castor might do, does not mean i am dumb enough to be the guinne pig. ;) rd | ||
| RVR OVR (Tom) Senior Member Username: Tom Post Number: 802 Registered: 07-2001 |
Oh yeah, it does change the angle. For me, it meant my front shaft had to go as it was all out of whack and vibing. A CV Shaft corrected that problem. Tom | ||
| Rob Davison (Nosivad_bor) Dweb Lounge Member Username: Nosivad_bor Post Number: 726 Registered: 02-2003 |
tom, how does it change the angle ? the whole purpose of doing the swivel balls is so that everything stays the same bewteen them. i guess that is to say if you had 6" spring lift your drive line is going to vib, but if you have 2" lift with balls done it should not vib. when with 2" lift and castor correcting arms, you would have vib's rd | ||
| Brian Dickens (Bri) Senior Member Username: Bri Post Number: 528 Registered: 08-2002 |
I don't think the arms will do anything for the vibes in the driveline. But will correct caster. | ||
| eric johnson (Eric2) Member Username: Eric2 Post Number: 58 Registered: 05-2003 |
Caster corrected swivel balls - for a 3" lift should: 1) Correct the caster angle 2) Allow you to use the stock front drive shaft | ||
| RVR OVR (Tom) Senior Member Username: Tom Post Number: 803 Registered: 07-2001 |
Rob, not the balls, the radius arms. Using that method rotates the axle, changing the pinion angle. Tom | ||
| Rob Davison (Nosivad_bor) Dweb Lounge Member Username: Nosivad_bor Post Number: 732 Registered: 02-2003 |
CASTOR CORRECTION HAS NO BALLS! hehe ok, i think we are on the same page. | ||
| John Lee (Johnlee) Dweb Lounge Member Username: Johnlee Post Number: 287 Registered: 03-2003 |
Yes, the caster-corrected arms will affect the driveline angle because the bent arms will force the front pinion to point more downward, away from the transfer case output shaft. You might be able to fit the factory front driveshaft and not get vibes. I say "might" because the front driveshaft is out of phase from the factory and very sensitive to changes in angle. Also, the front driveshaft is very short and suffers a severe angle change with tall lifts. Even if the caster-corrected arms changed the pinion angle enough that both ends of the front driveshaft were parallel to each other, the bends in the front driveshaft might be more than the driveshaft can handle. One thing for sure, the caster-corrected arms are terrible with the CV front driveshaft. A CV driveshaft wants zero or close to zero angle on the non-CV end. Introducing angle to the driveshaft on the pinion end will is very likely to induce driveline vibes. Wouldn't it be simpler just to fit a front TT? | ||
| Peter Matusov (Pmatusov) Senior Member Username: Pmatusov Post Number: 945 Registered: 09-2002 |
one more option is possible to mitigate the loss of directional stability - to set the toe-in at zero or 1/8" in. | ||
| RVR OVR (Tom) Senior Member Username: Tom Post Number: 804 Registered: 07-2001 |
To go back and do it all over again, I would do the TT first and then do castor correction if it was necessary. For me, the CV shaft matched up with the pinion angle perfectly with the RTE arms. I have no idea the specs on the arms, I just know he gave me what was to be combined with the 3" springs. In reality, I bought the Front CV before I understood much about driveline angles (not that I am an expert by any means now). I was just real lucky that the planets lined up and it worked perfectly. Just a side note on CV shafts - if you are going to buy one, go with a Double CV. For the $50 more you can rid yourself of driveline angle worries. Tom |
